From 033c843d4ae15e43a0ba0cd5b75e7d93cc21df1d Mon Sep 17 00:00:00 2001
From: konstantin <konstantin.klein@hochfrequenz.de>
Date: Thu, 1 Feb 2024 19:11:28 +0000
Subject: [PATCH 01/13] =?UTF-8?q?=F0=9F=94=92Enable=20Authentication?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 .../TransformerBeeClient/RestClient.cs        | 164 +++++++++++++++++-
 .../TransformerBeeClient.csproj               |   2 +
 2 files changed, 159 insertions(+), 7 deletions(-)

diff --git a/TransformerBeeClient/TransformerBeeClient/RestClient.cs b/TransformerBeeClient/TransformerBeeClient/RestClient.cs
index 024558d..f05547d 100644
--- a/TransformerBeeClient/TransformerBeeClient/RestClient.cs
+++ b/TransformerBeeClient/TransformerBeeClient/RestClient.cs
@@ -1,8 +1,13 @@
+using System.Net.Http.Headers;
+using System.Security.Authentication;
 using System.Text;
 using System.Text.Json;
 using System.Text.Json.Serialization;
 using EDILibrary;
 using TransformerBeeClient.Model;
+using IdentityModel.Client;
+using System.IdentityModel.Tokens.Jwt;
+using System.Net;
 
 namespace TransformerBeeClient;
 
@@ -11,7 +16,32 @@ namespace TransformerBeeClient;
 /// </summary>
 public class TransformerBeeRestClient : ICanConvertToBo4e, ICanConvertToEdifact
 {
+    protected const string Auth0Domain = "https://hochfrequenz.eu.auth0.com";
+    protected const string TransformerBeeScope = "client:default";
+    protected const string TransformerAudience = "https://transformer.bee";
+
+    /// <summary>
+    /// JWT token
+    /// </summary>
+    private string? _token;
+
+
+    /// <summary>
+    /// true iff the client should use authentication
+    /// </summary>
+    private bool UseAuthentication { get; }
+
+    private readonly string? _clientSecret;
+    private readonly string? _clientId;
+
+    /// <summary>
+    /// prevents us from requesting multiple tokens at the same time
+    /// </summary>
+    private readonly SemaphoreSlim _tokenRequestSemaphore = new(1, 1);
+
+
     private readonly HttpClient _httpClient;
+
     private readonly JsonSerializerOptions _jsonSerializerOptions = new()
     {
         PropertyNameCaseInsensitive = true,
@@ -20,17 +50,123 @@ public class TransformerBeeRestClient : ICanConvertToBo4e, ICanConvertToEdifact
 
     /// <summary>
     /// Provide the constructor with a http client factory.
-    /// It will create a client from said factory and use the <paramref name="clientName"/> for that.
+    /// It will create a client from said factory and use the <paramref name="httpClientName"/> for that.
     /// </summary>
     /// <param name="httpClientFactory">factory to create the http client from</param>
-    /// <param name="clientName">name used to create the client</param>
+    /// <param name="clientSecret">OAuth2 client ID</param>
+    /// <param name="httpClientName">name used to create the client</param>
+    /// <param name="clientId">OAuth2 client secret</param>
     /// <remarks>Find the OpenAPI Spec here: https://transformerstage.utilibee.io/swagger/index.html</remarks>
-    public TransformerBeeRestClient(IHttpClientFactory httpClientFactory, string clientName = "TransformerBee")
+    public TransformerBeeRestClient(IHttpClientFactory httpClientFactory, string? clientId = null, string? clientSecret = null, string httpClientName = "TransformerBee")
     {
-        _httpClient = httpClientFactory.CreateClient(clientName);
+        _httpClient = httpClientFactory.CreateClient(httpClientName);
         if (_httpClient.BaseAddress == null)
         {
-            throw new ArgumentNullException(nameof(httpClientFactory), $"The http client factory must provide a base address for the client with name '{clientName}'");
+            throw new ArgumentNullException(nameof(httpClientFactory), $"The http client factory must provide a base address for the client with name '{httpClientName}'");
+        }
+
+        if (!string.IsNullOrWhiteSpace(clientId) && string.IsNullOrWhiteSpace(clientSecret))
+        {
+            throw new ArgumentNullException(nameof(clientSecret), $"If you provide a {nameof(clientId)} you must also provide a {nameof(clientSecret)}");
+        }
+
+        if (!string.IsNullOrWhiteSpace(clientSecret) && string.IsNullOrWhiteSpace(clientId))
+        {
+            throw new ArgumentNullException(nameof(clientId), $"If you provide a {nameof(clientSecret)} you must also provide a {nameof(clientId)}");
+        }
+
+        UseAuthentication = !string.IsNullOrWhiteSpace(clientId) && !string.IsNullOrWhiteSpace(clientSecret);
+        if (UseAuthentication)
+        {
+            _clientId = clientId;
+            _clientSecret = clientSecret;
+        }
+    }
+
+    /// <summary>
+    /// returns true if the <see cref="token"/> will expire in the next 5 minutes
+    /// </summary>
+    /// <param name="token">jwt</param>
+    /// <returns>true if the token should be refreshed</returns>
+    private static bool TokenNeedsToBeRefreshed(string token)
+    {
+        ArgumentNullException.ThrowIfNull(token);
+        var handler = new JwtSecurityTokenHandler();
+        var jwtToken = handler.ReadToken(token) as JwtSecurityToken;
+        if (jwtToken == null) return true; // Assume renewal if token cannot be read
+        var expiry = jwtToken.ValidTo;
+        // Consider a buffer to renew the token a bit before it actually expires
+        var buffer = TimeSpan.FromMinutes(5);
+        return DateTime.UtcNow.Add(buffer) >= expiry;
+    }
+
+    /// <summary>
+    /// gets the oauth2 discovery document from the respective auth0 domain
+    /// </summary>
+    /// <returns></returns>
+    /// <exception cref="AuthenticationException"></exception>
+    private async Task<DiscoveryDocumentResponse> GetDiscoveryDocument()
+    {
+        var discoveryDocument = await _httpClient.GetDiscoveryDocumentAsync(Auth0Domain);
+        if (discoveryDocument.IsError)
+        {
+            throw new AuthenticationException($"Could not get discovery document from auth0: {discoveryDocument.Error}");
+        }
+
+        return discoveryDocument;
+    }
+
+    /// <summary>
+    /// fetch a token to talk to the transformer bee
+    /// </summary>
+    /// <returns>the token</returns>
+    /// <exception cref="AuthenticationException">if something goes wrong</exception>
+    private async Task<string> GetTokenAsync()
+    {
+        using (_tokenRequestSemaphore)
+        {
+            if (!UseAuthentication)
+            {
+                throw new AuthenticationException("You must provide a client id and a client secret to the constructor to authenticate with the transformer bee");
+            }
+
+            if (!string.IsNullOrWhiteSpace(_token) && !TokenNeedsToBeRefreshed(_token))
+            {
+                return _token;
+            }
+
+            var discoveryDocument = await GetDiscoveryDocument();
+            var tokenRequest = new ClientCredentialsTokenRequest
+            {
+                Address = discoveryDocument.TokenEndpoint,
+                ClientId = _clientId!,
+                ClientSecret = _clientSecret!,
+                GrantType = "client_credentials",
+                Scope = TransformerBeeScope,
+            };
+            tokenRequest.Parameters.AddOptional("audience", TransformerAudience);
+
+            var tokenResponse = await _httpClient.RequestClientCredentialsTokenAsync(tokenRequest);
+            if (tokenResponse.IsError)
+            {
+                throw new AuthenticationException($"Could not get token from auth0: {tokenResponse.Error}");
+            }
+
+            _token = tokenResponse.AccessToken!;
+        }
+
+        return _token;
+    }
+
+    /// <summary>
+    /// Make sure that the client is authenticated, if necessary
+    /// </summary>
+    private async Task EnsureAuthentication()
+    {
+        if (UseAuthentication)
+        {
+            var token = await GetTokenAsync();
+            _httpClient.DefaultRequestHeaders.Authorization = new AuthenticationHeaderValue("Bearer", token);
         }
     }
 
@@ -69,6 +205,7 @@ public async Task<List<Marktnachricht>> ConvertToBo4e(string edifact, EdifactFor
         {
             throw new ArgumentNullException(nameof(edifact));
         }
+
         var uriBuilder = new UriBuilder(_httpClient!.BaseAddress!)
         {
             Path = "/v1/transformer/EdiToBo4E"
@@ -81,12 +218,18 @@ public async Task<List<Marktnachricht>> ConvertToBo4e(string edifact, EdifactFor
             FormatVersion = formatVersion,
         };
         var requestJson = JsonSerializer.Serialize(request, _jsonSerializerOptions);
+        await EnsureAuthentication();
         var httpResponse = await _httpClient.PostAsync(convertUrl, new StringContent(requestJson, Encoding.UTF8, "application/json"));
         if (!httpResponse.IsSuccessStatusCode)
         {
-            // e.g. 401
+            if (httpResponse.StatusCode == HttpStatusCode.Unauthorized && !UseAuthentication)
+            {
+                throw new AuthenticationException("You have to provide client id and client secret to the constructor to authenticate yourself against transformer bee.");
+            }
+
             throw new HttpRequestException($"Could not convert {edifact} to BO4E. Status code: {httpResponse.StatusCode}");
         }
+
         var responseContent = await httpResponse.Content.ReadAsStringAsync();
         var bo4eResponse = JsonSerializer.Deserialize<EdifactToBo4eResponse>(responseContent, _jsonSerializerOptions);
         // todo: handle the case that the deserialization fails and bo4eResponse is null
@@ -102,6 +245,7 @@ public async Task<string> ConvertToEdifact(BOneyComb boneyComb, EdifactFormatVer
         {
             throw new ArgumentNullException(nameof(boneyComb));
         }
+
         var uriBuilder = new UriBuilder(_httpClient!.BaseAddress!)
         {
             Path = "/v1/transformer/Bo4ETransactionToEdi"
@@ -115,12 +259,18 @@ public async Task<string> ConvertToEdifact(BOneyComb boneyComb, EdifactFormatVer
             FormatVersion = formatVersion,
         };
         var requestJson = JsonSerializer.Serialize(request, _jsonSerializerOptions);
+        await EnsureAuthentication();
         var httpResponse = await _httpClient.PostAsync(convertUrl, new StringContent(requestJson, Encoding.UTF8, "application/json"));
         if (!httpResponse.IsSuccessStatusCode)
         {
-            // e.g. 401
+            if (httpResponse.StatusCode == HttpStatusCode.Unauthorized && !UseAuthentication)
+            {
+                throw new AuthenticationException("You have to provide client id and client secret to the constructor to authenticate yourself against transformer bee.");
+            }
+
             throw new HttpRequestException($"Could not convert to EDIFACT; Status code: {httpResponse.StatusCode}");
         }
+
         var responseContent = await httpResponse.Content.ReadAsStringAsync();
         // todo: ensure that the deserialization does not fail and the response is not empty
         var responseBody = JsonSerializer.Deserialize<Bo4eTransactionToEdifactResponse>(responseContent!, _jsonSerializerOptions);
diff --git a/TransformerBeeClient/TransformerBeeClient/TransformerBeeClient.csproj b/TransformerBeeClient/TransformerBeeClient/TransformerBeeClient.csproj
index 42d5454..5489d3b 100644
--- a/TransformerBeeClient/TransformerBeeClient/TransformerBeeClient.csproj
+++ b/TransformerBeeClient/TransformerBeeClient/TransformerBeeClient.csproj
@@ -13,7 +13,9 @@
     <ItemGroup>
       <PackageReference Include="EDILibrary.Core" Version="1.5.9" />
       <PackageReference Include="Hochfrequenz.BO4Enet" Version="0.2.147" />
+      <PackageReference Include="IdentityModel" Version="6.2.0" />
       <PackageReference Include="Microsoft.Extensions.Http" Version="8.0.0" />
+      <PackageReference Include="System.IdentityModel.Tokens.Jwt" Version="7.3.0" />
     </ItemGroup>
 
 </Project>

From 7c20429f545f46a269231895d004530ade977cf6 Mon Sep 17 00:00:00 2001
From: konstantin <konstantin.klein@hochfrequenz.de>
Date: Thu, 1 Feb 2024 19:40:31 +0000
Subject: [PATCH 02/13] restructure

---
 .../Bo4eToEdifactTests.cs                     |   4 +-
 .../ClientFixture.cs                          |   3 +
 .../ConnectionTests.cs                        |   6 +-
 .../EdifactToBo4eTests.cs                     |   5 +-
 .../ConnectionTests.cs                        |   2 +-
 .../TransformerBeeClient/Class1.cs            |   5 -
 .../ClientIdClientSecretTokenProvider.cs      | 136 +++++++++++++++++
 .../TransformerBeeClient/Interfaces.cs        |  18 +++
 .../NoAuthenticationProvider.cs               |  14 ++
 .../TransformerBeeClient/RestClient.cs        | 140 ++----------------
 10 files changed, 196 insertions(+), 137 deletions(-)
 delete mode 100644 TransformerBeeClient/TransformerBeeClient/Class1.cs
 create mode 100644 TransformerBeeClient/TransformerBeeClient/ClientIdClientSecretTokenProvider.cs
 create mode 100644 TransformerBeeClient/TransformerBeeClient/NoAuthenticationProvider.cs

diff --git a/TransformerBeeClient/TransformerBeeClient.IntegrationTest/Bo4eToEdifactTests.cs b/TransformerBeeClient/TransformerBeeClient.IntegrationTest/Bo4eToEdifactTests.cs
index 63079dd..a16767a 100644
--- a/TransformerBeeClient/TransformerBeeClient.IntegrationTest/Bo4eToEdifactTests.cs
+++ b/TransformerBeeClient/TransformerBeeClient.IntegrationTest/Bo4eToEdifactTests.cs
@@ -13,17 +13,19 @@ namespace TransformerBeeClient.IntegrationTest;
 public class Bo4eToEdifactTests : IClassFixture<ClientFixture>
 {
     private readonly ClientFixture _client;
+    private readonly ITransformerBeeAuthenticationProvider _authenticationProvider;
 
     public Bo4eToEdifactTests(ClientFixture clientFixture)
     {
         _client = clientFixture;
+        _authenticationProvider = clientFixture.AuthenticationProvider;
     }
 
     [Fact]
     public async Task BOneyComb_Can_Be_Converted_To_Edifact()
     {
         var httpClientFactory = _client.HttpClientFactory;
-        ICanConvertToEdifact client = new TransformerBeeRestClient(httpClientFactory);
+        ICanConvertToEdifact client = new TransformerBeeRestClient(httpClientFactory, _authenticationProvider);
         var boneyCombString = await File.ReadAllTextAsync("TestEdifacts/FV2310/55001.json");
         var deserializerOptions = new JsonSerializerOptions
         {
diff --git a/TransformerBeeClient/TransformerBeeClient.IntegrationTest/ClientFixture.cs b/TransformerBeeClient/TransformerBeeClient.IntegrationTest/ClientFixture.cs
index 9556601..cbc8b99 100644
--- a/TransformerBeeClient/TransformerBeeClient.IntegrationTest/ClientFixture.cs
+++ b/TransformerBeeClient/TransformerBeeClient.IntegrationTest/ClientFixture.cs
@@ -12,6 +12,8 @@ public class ClientFixture : IClassFixture<ClientFixture>
 
     public readonly ServiceCollection ServiceCollection;
 
+    public readonly ITransformerBeeAuthenticationProvider AuthenticationProvider;
+    
     public ClientFixture()
     {
         var services = new ServiceCollection();
@@ -22,5 +24,6 @@ public ClientFixture()
         var serviceProvider = services.BuildServiceProvider();
         ServiceCollection = services;
         HttpClientFactory = serviceProvider.GetService<IHttpClientFactory>();
+        AuthenticationProvider = new NoAuthenticationprovider(); // easy for integration tests with transformer.bee running in docker
     }
 }
diff --git a/TransformerBeeClient/TransformerBeeClient.IntegrationTest/ConnectionTests.cs b/TransformerBeeClient/TransformerBeeClient.IntegrationTest/ConnectionTests.cs
index 50e81a2..f2d2030 100644
--- a/TransformerBeeClient/TransformerBeeClient.IntegrationTest/ConnectionTests.cs
+++ b/TransformerBeeClient/TransformerBeeClient.IntegrationTest/ConnectionTests.cs
@@ -11,17 +11,19 @@ public class ConnectionTests : IClassFixture<ClientFixture>
 {
 
     private readonly ClientFixture _client;
+    private readonly ITransformerBeeAuthenticationProvider _authenticationProvider;
 
     public ConnectionTests(ClientFixture clientFixture)
     {
         _client = clientFixture;
+        _authenticationProvider = clientFixture.AuthenticationProvider;
     }
 
     [Fact]
     public async Task IsAvailable_Returns_True_If_Service_Is_Available()
     {
         var httpClientFactory = _client.HttpClientFactory;
-        var client = new TransformerBeeRestClient(httpClientFactory);
+        var client = new TransformerBeeRestClient(httpClientFactory, _authenticationProvider);
         var result = await client.IsAvailable();
         result.Should().BeTrue();
     }
@@ -35,7 +37,7 @@ public async Task IsAvailable_Throws_Exception_If_Host_Is_Unavailable()
             client.BaseAddress = new Uri("http://localhost:1234"); // <-- no service running under this address
         });
         var serviceProvider = services.BuildServiceProvider();
-        var client = new TransformerBeeRestClient(serviceProvider.GetService<IHttpClientFactory>());
+        var client = new TransformerBeeRestClient(serviceProvider.GetService<IHttpClientFactory>(), _authenticationProvider);
         var checkIfIsAvailable = async () => await client.IsAvailable();
         await checkIfIsAvailable.Should().ThrowAsync<HttpRequestException>();
     }
diff --git a/TransformerBeeClient/TransformerBeeClient.IntegrationTest/EdifactToBo4eTests.cs b/TransformerBeeClient/TransformerBeeClient.IntegrationTest/EdifactToBo4eTests.cs
index e18f0ed..e7b68b0 100644
--- a/TransformerBeeClient/TransformerBeeClient.IntegrationTest/EdifactToBo4eTests.cs
+++ b/TransformerBeeClient/TransformerBeeClient.IntegrationTest/EdifactToBo4eTests.cs
@@ -11,17 +11,20 @@ namespace TransformerBeeClient.IntegrationTest;
 public class EdifactToBo4eTests : IClassFixture<ClientFixture>
 {
     private readonly ClientFixture _client;
+    
+    private readonly ITransformerBeeAuthenticationProvider _authenticationProvider;
 
     public EdifactToBo4eTests(ClientFixture clientFixture)
     {
         _client = clientFixture;
+        _authenticationProvider = clientFixture.AuthenticationProvider;
     }
 
     [Fact]
     public async Task Edifact_Can_Be_Converted_To_Bo4e()
     {
         var httpClientFactory = _client.HttpClientFactory;
-        ICanConvertToBo4e client = new TransformerBeeRestClient(httpClientFactory);
+        ICanConvertToBo4e client = new TransformerBeeRestClient(httpClientFactory, _authenticationProvider);
         var edifactString = await File.ReadAllTextAsync("TestEdifacts/FV2310/55001.edi");
         var result = await client.ConvertToBo4e(edifactString, EdifactFormatVersion.FV2310);
         result.Should().BeOfType<List<Marktnachricht>>();
diff --git a/TransformerBeeClient/TransformerBeeClient.UnitTest/ConnectionTests.cs b/TransformerBeeClient/TransformerBeeClient.UnitTest/ConnectionTests.cs
index e770442..6f50073 100644
--- a/TransformerBeeClient/TransformerBeeClient.UnitTest/ConnectionTests.cs
+++ b/TransformerBeeClient/TransformerBeeClient.UnitTest/ConnectionTests.cs
@@ -15,7 +15,7 @@ public void IsAvailable_Throws_ArgumentNullException_If_BaseAddress_Is_Not_Confi
             client.BaseAddress = null;
         });
         var serviceProvider = services.BuildServiceProvider();
-        var instantiateClient = () => new TransformerBeeRestClient(serviceProvider.GetService<IHttpClientFactory>());
+        var instantiateClient = () => new TransformerBeeRestClient(serviceProvider.GetService<IHttpClientFactory>(), new NoAuthenticationprovider());
         instantiateClient.Should().Throw<ArgumentNullException>();
     }
 }
diff --git a/TransformerBeeClient/TransformerBeeClient/Class1.cs b/TransformerBeeClient/TransformerBeeClient/Class1.cs
deleted file mode 100644
index 768b84c..0000000
--- a/TransformerBeeClient/TransformerBeeClient/Class1.cs
+++ /dev/null
@@ -1,5 +0,0 @@
-namespace TransformerBeeClient;
-
-public class Class1
-{
-}
\ No newline at end of file
diff --git a/TransformerBeeClient/TransformerBeeClient/ClientIdClientSecretTokenProvider.cs b/TransformerBeeClient/TransformerBeeClient/ClientIdClientSecretTokenProvider.cs
new file mode 100644
index 0000000..2616d2f
--- /dev/null
+++ b/TransformerBeeClient/TransformerBeeClient/ClientIdClientSecretTokenProvider.cs
@@ -0,0 +1,136 @@
+namespace TransformerBeeClient;
+
+using System.Security.Authentication;
+using IdentityModel.Client;
+using System.IdentityModel.Tokens.Jwt;
+
+/// <summary>
+/// a <see cref="ITransformerBeeAuthenticationProvider"/> that is based on a client secret and a client id
+/// </summary>
+public class ClientIdClientSecretAuthenticationProvider : ITransformerBeeAuthenticationProvider
+{
+    protected const string Auth0Domain = "https://hochfrequenz.eu.auth0.com";
+    protected const string TransformerBeeScope = "client:default";
+    protected const string TransformerAudience = "https://transformer.bee";
+
+    /// <summary>
+    /// JWT token
+    /// </summary>
+    private string? _token;
+
+    private readonly string? _clientSecret;
+    private readonly string? _clientId;
+
+    /// <summary>
+    /// true iff the client should use authentication
+    /// </summary>
+    private readonly bool _useAuthentication;
+
+    /// <summary>
+    /// <inheritdoc cref="ITransformerBeeAuthenticationProvider.UseAuthentication"/>
+    /// </summary>
+    public bool UseAuthentication() => _useAuthentication;
+
+    /// <summary>
+    /// prevents us from requesting multiple tokens at the same time
+    /// </summary>
+    private readonly SemaphoreSlim _tokenRequestSemaphore = new(1, 1);
+
+    /// <summary>A <see cref="ITransformerBeeAuthenticationProvider"/> that is based on a client secret and a client id</summary>
+    /// <param name="clientId">OAuth2 client secret (ask Hochfrequenz)</param>
+    /// <param name="clientSecret">OAuth2 client ID (ask Hochfrequenz)</param>
+    public ClientIdClientSecretAuthenticationProvider(string? clientId, string? clientSecret)
+    {
+        if (!string.IsNullOrWhiteSpace(clientId) && string.IsNullOrWhiteSpace(clientSecret))
+        {
+            throw new ArgumentNullException(nameof(clientSecret), $"If you provide a {nameof(clientId)} you must also provide a {nameof(clientSecret)}");
+        }
+
+        if (!string.IsNullOrWhiteSpace(clientSecret) && string.IsNullOrWhiteSpace(clientId))
+        {
+            throw new ArgumentNullException(nameof(clientId), $"If you provide a {nameof(clientSecret)} you must also provide a {nameof(clientId)}");
+        }
+
+        _useAuthentication = !string.IsNullOrWhiteSpace(clientId) && !string.IsNullOrWhiteSpace(clientSecret);
+        if (_useAuthentication)
+        {
+            _clientId = clientId;
+            _clientSecret = clientSecret;
+        }
+    }
+
+    /// <summary>
+    /// returns true if the <see cref="token"/> will expire in the next 5 minutes
+    /// </summary>
+    /// <param name="token">jwt</param>
+    /// <returns>true if the token should be refreshed</returns>
+    private static bool TokenNeedsToBeRefreshed(string token)
+    {
+        ArgumentNullException.ThrowIfNull(token);
+        var handler = new JwtSecurityTokenHandler();
+        var jwtToken = handler.ReadToken(token) as JwtSecurityToken;
+        if (jwtToken == null) return true; // Assume renewal if token cannot be read
+        var expiry = jwtToken.ValidTo;
+        // Consider a buffer to renew the token a bit before it actually expires
+        var buffer = TimeSpan.FromMinutes(5);
+        return DateTime.UtcNow.Add(buffer) >= expiry;
+    }
+
+    /// <summary>
+    /// gets the oauth2 discovery document from the respective auth0 domain
+    /// </summary>
+    /// <returns></returns>
+    /// <exception cref="AuthenticationException"></exception>
+    private static async Task<DiscoveryDocumentResponse> GetDiscoveryDocument(HttpClient client)
+    {
+        var discoveryDocument = await client.GetDiscoveryDocumentAsync(Auth0Domain);
+        if (discoveryDocument.IsError)
+        {
+            throw new AuthenticationException($"Could not get discovery document from auth0: {discoveryDocument.Error}");
+        }
+
+        return discoveryDocument;
+    }
+
+    /// <summary>
+    /// fetch a token to talk to the transformer bee
+    /// </summary>
+    /// <returns>the token</returns>
+    /// <exception cref="AuthenticationException">if something goes wrong</exception>
+    public async Task<string> GetTokenAsync(HttpClient client)
+    {
+        using (_tokenRequestSemaphore)
+        {
+            if (!UseAuthentication())
+            {
+                throw new AuthenticationException("You must provide a client id and a client secret to the constructor to authenticate with the transformer bee");
+            }
+
+            if (!string.IsNullOrWhiteSpace(_token) && !TokenNeedsToBeRefreshed(_token))
+            {
+                return _token;
+            }
+
+            var discoveryDocument = await GetDiscoveryDocument(client);
+            var tokenRequest = new ClientCredentialsTokenRequest
+            {
+                Address = discoveryDocument.TokenEndpoint,
+                ClientId = _clientId!,
+                ClientSecret = _clientSecret!,
+                GrantType = "client_credentials",
+                Scope = TransformerBeeScope,
+            };
+            tokenRequest.Parameters.AddOptional("audience", TransformerAudience);
+
+            var tokenResponse = await client.RequestClientCredentialsTokenAsync(tokenRequest);
+            if (tokenResponse.IsError)
+            {
+                throw new AuthenticationException($"Could not get token from auth0: {tokenResponse.Error}");
+            }
+
+            _token = tokenResponse.AccessToken!;
+        }
+
+        return _token;
+    }
+}
diff --git a/TransformerBeeClient/TransformerBeeClient/Interfaces.cs b/TransformerBeeClient/TransformerBeeClient/Interfaces.cs
index 0398e0e..b28f8dc 100644
--- a/TransformerBeeClient/TransformerBeeClient/Interfaces.cs
+++ b/TransformerBeeClient/TransformerBeeClient/Interfaces.cs
@@ -32,3 +32,21 @@ public interface ICanConvertToEdifact
     /// <returns>the edifact as plain string</returns>
     public Task<string> ConvertToEdifact(BOneyComb boneyComb, EdifactFormatVersion formatVersion);
 }
+
+/// <summary>
+/// Can provide information on whether you need to authenticate against transformer.bee and how
+/// </summary>
+public interface ITransformerBeeAuthenticationProvider
+{
+    /// <summary>
+    /// returns true iff the client should use authentication
+    /// </summary>
+    /// <returns></returns>
+    public bool UseAuthentication();
+    
+    /// <summary>
+    /// provides the token to authenticate against transformer.bee (if and only if <see cref="UseAuthentication"/> is true)
+    /// </summary>
+    /// <returns></returns>
+    public Task<string> GetTokenAsync(HttpClient client);
+}
diff --git a/TransformerBeeClient/TransformerBeeClient/NoAuthenticationProvider.cs b/TransformerBeeClient/TransformerBeeClient/NoAuthenticationProvider.cs
new file mode 100644
index 0000000..769c847
--- /dev/null
+++ b/TransformerBeeClient/TransformerBeeClient/NoAuthenticationProvider.cs
@@ -0,0 +1,14 @@
+namespace TransformerBeeClient;
+
+/// <summary>
+/// a <see cref="ITransformerBeeAuthenticationProvider"/> stub that just indicates, we don't need to authenticate against transformer.bee, because we're e.g. in the same network
+/// </summary>
+public class NoAuthenticationprovider : ITransformerBeeAuthenticationProvider
+{
+    public bool UseAuthentication() => false;
+
+    public Task<string> GetTokenAsync(HttpClient client)
+    {
+        throw new NotImplementedException("This must never be called, because we don't use authentication.");
+    }
+}
diff --git a/TransformerBeeClient/TransformerBeeClient/RestClient.cs b/TransformerBeeClient/TransformerBeeClient/RestClient.cs
index f05547d..d9a60df 100644
--- a/TransformerBeeClient/TransformerBeeClient/RestClient.cs
+++ b/TransformerBeeClient/TransformerBeeClient/RestClient.cs
@@ -1,13 +1,11 @@
-using System.Net.Http.Headers;
 using System.Security.Authentication;
 using System.Text;
 using System.Text.Json;
 using System.Text.Json.Serialization;
 using EDILibrary;
 using TransformerBeeClient.Model;
-using IdentityModel.Client;
-using System.IdentityModel.Tokens.Jwt;
 using System.Net;
+using System.Net.Http.Headers;
 
 namespace TransformerBeeClient;
 
@@ -16,30 +14,7 @@ namespace TransformerBeeClient;
 /// </summary>
 public class TransformerBeeRestClient : ICanConvertToBo4e, ICanConvertToEdifact
 {
-    protected const string Auth0Domain = "https://hochfrequenz.eu.auth0.com";
-    protected const string TransformerBeeScope = "client:default";
-    protected const string TransformerAudience = "https://transformer.bee";
-
-    /// <summary>
-    /// JWT token
-    /// </summary>
-    private string? _token;
-
-
-    /// <summary>
-    /// true iff the client should use authentication
-    /// </summary>
-    private bool UseAuthentication { get; }
-
-    private readonly string? _clientSecret;
-    private readonly string? _clientId;
-
-    /// <summary>
-    /// prevents us from requesting multiple tokens at the same time
-    /// </summary>
-    private readonly SemaphoreSlim _tokenRequestSemaphore = new(1, 1);
-
-
+    private readonly ITransformerBeeAuthenticationProvider _authenticationProvider;
     private readonly HttpClient _httpClient;
 
     private readonly JsonSerializerOptions _jsonSerializerOptions = new()
@@ -53,11 +28,10 @@ public class TransformerBeeRestClient : ICanConvertToBo4e, ICanConvertToEdifact
     /// It will create a client from said factory and use the <paramref name="httpClientName"/> for that.
     /// </summary>
     /// <param name="httpClientFactory">factory to create the http client from</param>
-    /// <param name="clientSecret">OAuth2 client ID</param>
+    /// <param name="authenticationProvider">something that tells you whether and how you need to authenticate yourself at transformer.bee</param>
     /// <param name="httpClientName">name used to create the client</param>
-    /// <param name="clientId">OAuth2 client secret</param>
     /// <remarks>Find the OpenAPI Spec here: https://transformerstage.utilibee.io/swagger/index.html</remarks>
-    public TransformerBeeRestClient(IHttpClientFactory httpClientFactory, string? clientId = null, string? clientSecret = null, string httpClientName = "TransformerBee")
+    public TransformerBeeRestClient(IHttpClientFactory httpClientFactory, ITransformerBeeAuthenticationProvider authenticationProvider, string httpClientName = "TransformerBee")
     {
         _httpClient = httpClientFactory.CreateClient(httpClientName);
         if (_httpClient.BaseAddress == null)
@@ -65,97 +39,7 @@ public TransformerBeeRestClient(IHttpClientFactory httpClientFactory, string? cl
             throw new ArgumentNullException(nameof(httpClientFactory), $"The http client factory must provide a base address for the client with name '{httpClientName}'");
         }
 
-        if (!string.IsNullOrWhiteSpace(clientId) && string.IsNullOrWhiteSpace(clientSecret))
-        {
-            throw new ArgumentNullException(nameof(clientSecret), $"If you provide a {nameof(clientId)} you must also provide a {nameof(clientSecret)}");
-        }
-
-        if (!string.IsNullOrWhiteSpace(clientSecret) && string.IsNullOrWhiteSpace(clientId))
-        {
-            throw new ArgumentNullException(nameof(clientId), $"If you provide a {nameof(clientSecret)} you must also provide a {nameof(clientId)}");
-        }
-
-        UseAuthentication = !string.IsNullOrWhiteSpace(clientId) && !string.IsNullOrWhiteSpace(clientSecret);
-        if (UseAuthentication)
-        {
-            _clientId = clientId;
-            _clientSecret = clientSecret;
-        }
-    }
-
-    /// <summary>
-    /// returns true if the <see cref="token"/> will expire in the next 5 minutes
-    /// </summary>
-    /// <param name="token">jwt</param>
-    /// <returns>true if the token should be refreshed</returns>
-    private static bool TokenNeedsToBeRefreshed(string token)
-    {
-        ArgumentNullException.ThrowIfNull(token);
-        var handler = new JwtSecurityTokenHandler();
-        var jwtToken = handler.ReadToken(token) as JwtSecurityToken;
-        if (jwtToken == null) return true; // Assume renewal if token cannot be read
-        var expiry = jwtToken.ValidTo;
-        // Consider a buffer to renew the token a bit before it actually expires
-        var buffer = TimeSpan.FromMinutes(5);
-        return DateTime.UtcNow.Add(buffer) >= expiry;
-    }
-
-    /// <summary>
-    /// gets the oauth2 discovery document from the respective auth0 domain
-    /// </summary>
-    /// <returns></returns>
-    /// <exception cref="AuthenticationException"></exception>
-    private async Task<DiscoveryDocumentResponse> GetDiscoveryDocument()
-    {
-        var discoveryDocument = await _httpClient.GetDiscoveryDocumentAsync(Auth0Domain);
-        if (discoveryDocument.IsError)
-        {
-            throw new AuthenticationException($"Could not get discovery document from auth0: {discoveryDocument.Error}");
-        }
-
-        return discoveryDocument;
-    }
-
-    /// <summary>
-    /// fetch a token to talk to the transformer bee
-    /// </summary>
-    /// <returns>the token</returns>
-    /// <exception cref="AuthenticationException">if something goes wrong</exception>
-    private async Task<string> GetTokenAsync()
-    {
-        using (_tokenRequestSemaphore)
-        {
-            if (!UseAuthentication)
-            {
-                throw new AuthenticationException("You must provide a client id and a client secret to the constructor to authenticate with the transformer bee");
-            }
-
-            if (!string.IsNullOrWhiteSpace(_token) && !TokenNeedsToBeRefreshed(_token))
-            {
-                return _token;
-            }
-
-            var discoveryDocument = await GetDiscoveryDocument();
-            var tokenRequest = new ClientCredentialsTokenRequest
-            {
-                Address = discoveryDocument.TokenEndpoint,
-                ClientId = _clientId!,
-                ClientSecret = _clientSecret!,
-                GrantType = "client_credentials",
-                Scope = TransformerBeeScope,
-            };
-            tokenRequest.Parameters.AddOptional("audience", TransformerAudience);
-
-            var tokenResponse = await _httpClient.RequestClientCredentialsTokenAsync(tokenRequest);
-            if (tokenResponse.IsError)
-            {
-                throw new AuthenticationException($"Could not get token from auth0: {tokenResponse.Error}");
-            }
-
-            _token = tokenResponse.AccessToken!;
-        }
-
-        return _token;
+        _authenticationProvider = authenticationProvider ?? throw new ArgumentNullException(nameof(authenticationProvider));
     }
 
     /// <summary>
@@ -163,9 +47,9 @@ private async Task<string> GetTokenAsync()
     /// </summary>
     private async Task EnsureAuthentication()
     {
-        if (UseAuthentication)
+        if (_authenticationProvider.UseAuthentication())
         {
-            var token = await GetTokenAsync();
+            var token = await _authenticationProvider.GetTokenAsync(_httpClient);
             _httpClient.DefaultRequestHeaders.Authorization = new AuthenticationHeaderValue("Bearer", token);
         }
     }
@@ -189,6 +73,8 @@ public async Task<bool> IsAvailable()
 
         var versionUrl = uriBuilder.Uri.AbsoluteUri;
         var response = await _httpClient.GetAsync(versionUrl);
+        // note that this is available without any authentication
+        // see e.g. http://transformerstage.utilibee.io/version
         return response.IsSuccessStatusCode;
     }
 
@@ -222,9 +108,9 @@ public async Task<List<Marktnachricht>> ConvertToBo4e(string edifact, EdifactFor
         var httpResponse = await _httpClient.PostAsync(convertUrl, new StringContent(requestJson, Encoding.UTF8, "application/json"));
         if (!httpResponse.IsSuccessStatusCode)
         {
-            if (httpResponse.StatusCode == HttpStatusCode.Unauthorized && !UseAuthentication)
+            if (httpResponse.StatusCode == HttpStatusCode.Unauthorized && !_authenticationProvider.UseAuthentication())
             {
-                throw new AuthenticationException("You have to provide client id and client secret to the constructor to authenticate yourself against transformer bee.");
+                throw new AuthenticationException($"Did you correctly set up the {nameof(ITransformerBeeAuthenticationProvider)}?");
             }
 
             throw new HttpRequestException($"Could not convert {edifact} to BO4E. Status code: {httpResponse.StatusCode}");
@@ -263,9 +149,9 @@ public async Task<string> ConvertToEdifact(BOneyComb boneyComb, EdifactFormatVer
         var httpResponse = await _httpClient.PostAsync(convertUrl, new StringContent(requestJson, Encoding.UTF8, "application/json"));
         if (!httpResponse.IsSuccessStatusCode)
         {
-            if (httpResponse.StatusCode == HttpStatusCode.Unauthorized && !UseAuthentication)
+            if (httpResponse.StatusCode == HttpStatusCode.Unauthorized && !_authenticationProvider.UseAuthentication())
             {
-                throw new AuthenticationException("You have to provide client id and client secret to the constructor to authenticate yourself against transformer bee.");
+                throw new AuthenticationException($"Did you correctly set up the {nameof(ITransformerBeeAuthenticationProvider)}?");
             }
 
             throw new HttpRequestException($"Could not convert to EDIFACT; Status code: {httpResponse.StatusCode}");

From a9aec3612464c02bca6d7d78d498a2b5373b4e9d Mon Sep 17 00:00:00 2001
From: konstantin <konstantin.klein@hochfrequenz.de>
Date: Thu, 1 Feb 2024 19:42:21 +0000
Subject: [PATCH 03/13] format

---
 .../TransformerBeeClient.IntegrationTest/ClientFixture.cs       | 2 +-
 .../TransformerBeeClient.IntegrationTest/EdifactToBo4eTests.cs  | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/TransformerBeeClient/TransformerBeeClient.IntegrationTest/ClientFixture.cs b/TransformerBeeClient/TransformerBeeClient.IntegrationTest/ClientFixture.cs
index cbc8b99..dcbecfb 100644
--- a/TransformerBeeClient/TransformerBeeClient.IntegrationTest/ClientFixture.cs
+++ b/TransformerBeeClient/TransformerBeeClient.IntegrationTest/ClientFixture.cs
@@ -13,7 +13,7 @@ public class ClientFixture : IClassFixture<ClientFixture>
     public readonly ServiceCollection ServiceCollection;
 
     public readonly ITransformerBeeAuthenticationProvider AuthenticationProvider;
-    
+
     public ClientFixture()
     {
         var services = new ServiceCollection();
diff --git a/TransformerBeeClient/TransformerBeeClient.IntegrationTest/EdifactToBo4eTests.cs b/TransformerBeeClient/TransformerBeeClient.IntegrationTest/EdifactToBo4eTests.cs
index e7b68b0..741041f 100644
--- a/TransformerBeeClient/TransformerBeeClient.IntegrationTest/EdifactToBo4eTests.cs
+++ b/TransformerBeeClient/TransformerBeeClient.IntegrationTest/EdifactToBo4eTests.cs
@@ -11,7 +11,7 @@ namespace TransformerBeeClient.IntegrationTest;
 public class EdifactToBo4eTests : IClassFixture<ClientFixture>
 {
     private readonly ClientFixture _client;
-    
+
     private readonly ITransformerBeeAuthenticationProvider _authenticationProvider;
 
     public EdifactToBo4eTests(ClientFixture clientFixture)

From d65118ad6283a61cade13a07c553a49e00ef41c6 Mon Sep 17 00:00:00 2001
From: konstantin <konstantin.klein@hochfrequenz.de>
Date: Thu, 1 Feb 2024 19:42:57 +0000
Subject: [PATCH 04/13] boms

---
 .../TransformerBeeClient/ClientIdClientSecretTokenProvider.cs   | 2 +-
 TransformerBeeClient/TransformerBeeClient/Interfaces.cs         | 2 +-
 .../TransformerBeeClient/NoAuthenticationProvider.cs            | 2 +-
 3 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/TransformerBeeClient/TransformerBeeClient/ClientIdClientSecretTokenProvider.cs b/TransformerBeeClient/TransformerBeeClient/ClientIdClientSecretTokenProvider.cs
index 2616d2f..a8aa9f4 100644
--- a/TransformerBeeClient/TransformerBeeClient/ClientIdClientSecretTokenProvider.cs
+++ b/TransformerBeeClient/TransformerBeeClient/ClientIdClientSecretTokenProvider.cs
@@ -1,4 +1,4 @@
-namespace TransformerBeeClient;
+namespace TransformerBeeClient;
 
 using System.Security.Authentication;
 using IdentityModel.Client;
diff --git a/TransformerBeeClient/TransformerBeeClient/Interfaces.cs b/TransformerBeeClient/TransformerBeeClient/Interfaces.cs
index b28f8dc..d74cae7 100644
--- a/TransformerBeeClient/TransformerBeeClient/Interfaces.cs
+++ b/TransformerBeeClient/TransformerBeeClient/Interfaces.cs
@@ -43,7 +43,7 @@ public interface ITransformerBeeAuthenticationProvider
     /// </summary>
     /// <returns></returns>
     public bool UseAuthentication();
-    
+
     /// <summary>
     /// provides the token to authenticate against transformer.bee (if and only if <see cref="UseAuthentication"/> is true)
     /// </summary>
diff --git a/TransformerBeeClient/TransformerBeeClient/NoAuthenticationProvider.cs b/TransformerBeeClient/TransformerBeeClient/NoAuthenticationProvider.cs
index 769c847..aed1795 100644
--- a/TransformerBeeClient/TransformerBeeClient/NoAuthenticationProvider.cs
+++ b/TransformerBeeClient/TransformerBeeClient/NoAuthenticationProvider.cs
@@ -1,4 +1,4 @@
-namespace TransformerBeeClient;
+namespace TransformerBeeClient;
 
 /// <summary>
 /// a <see cref="ITransformerBeeAuthenticationProvider"/> stub that just indicates, we don't need to authenticate against transformer.bee, because we're e.g. in the same network

From f9c19ab4bae83a6b3d67d87b333d5e2e9c244a4b Mon Sep 17 00:00:00 2001
From: konstantin <konstantin.klein@hochfrequenz.de>
Date: Thu, 1 Feb 2024 19:47:06 +0000
Subject: [PATCH 05/13] typo and docs

---
 README.md                                                     | 4 ++++
 .../TransformerBeeClient.IntegrationTest/ClientFixture.cs     | 2 +-
 .../TransformerBeeClient.UnitTest/ConnectionTests.cs          | 2 +-
 .../TransformerBeeClient/NoAuthenticationProvider.cs          | 2 +-
 4 files changed, 7 insertions(+), 3 deletions(-)

diff --git a/README.md b/README.md
index ebe5d64..cbad941 100644
--- a/README.md
+++ b/README.md
@@ -24,6 +24,10 @@ dotnet add package TransformerBeeClient
 
 ### Use it in your code
 
+#### Authentication
+You need to provide something that implements `ITransformerBeeAuthenticator` to the `TransformerBeeClient`.
+If you're hosting transformer.bee in the same network and there is no authentication, you can use the `NoAuthenticationProvider` class.
+
 Then, you can use the client like this:
 
 ```csharp
diff --git a/TransformerBeeClient/TransformerBeeClient.IntegrationTest/ClientFixture.cs b/TransformerBeeClient/TransformerBeeClient.IntegrationTest/ClientFixture.cs
index dcbecfb..9223881 100644
--- a/TransformerBeeClient/TransformerBeeClient.IntegrationTest/ClientFixture.cs
+++ b/TransformerBeeClient/TransformerBeeClient.IntegrationTest/ClientFixture.cs
@@ -24,6 +24,6 @@ public ClientFixture()
         var serviceProvider = services.BuildServiceProvider();
         ServiceCollection = services;
         HttpClientFactory = serviceProvider.GetService<IHttpClientFactory>();
-        AuthenticationProvider = new NoAuthenticationprovider(); // easy for integration tests with transformer.bee running in docker
+        AuthenticationProvider = new NoAuthenticationProvider(); // easy for integration tests with transformer.bee running in docker
     }
 }
diff --git a/TransformerBeeClient/TransformerBeeClient.UnitTest/ConnectionTests.cs b/TransformerBeeClient/TransformerBeeClient.UnitTest/ConnectionTests.cs
index 6f50073..8614bf9 100644
--- a/TransformerBeeClient/TransformerBeeClient.UnitTest/ConnectionTests.cs
+++ b/TransformerBeeClient/TransformerBeeClient.UnitTest/ConnectionTests.cs
@@ -15,7 +15,7 @@ public void IsAvailable_Throws_ArgumentNullException_If_BaseAddress_Is_Not_Confi
             client.BaseAddress = null;
         });
         var serviceProvider = services.BuildServiceProvider();
-        var instantiateClient = () => new TransformerBeeRestClient(serviceProvider.GetService<IHttpClientFactory>(), new NoAuthenticationprovider());
+        var instantiateClient = () => new TransformerBeeRestClient(serviceProvider.GetService<IHttpClientFactory>(), new NoAuthenticationProvider());
         instantiateClient.Should().Throw<ArgumentNullException>();
     }
 }
diff --git a/TransformerBeeClient/TransformerBeeClient/NoAuthenticationProvider.cs b/TransformerBeeClient/TransformerBeeClient/NoAuthenticationProvider.cs
index aed1795..3c97cde 100644
--- a/TransformerBeeClient/TransformerBeeClient/NoAuthenticationProvider.cs
+++ b/TransformerBeeClient/TransformerBeeClient/NoAuthenticationProvider.cs
@@ -3,7 +3,7 @@ namespace TransformerBeeClient;
 /// <summary>
 /// a <see cref="ITransformerBeeAuthenticationProvider"/> stub that just indicates, we don't need to authenticate against transformer.bee, because we're e.g. in the same network
 /// </summary>
-public class NoAuthenticationprovider : ITransformerBeeAuthenticationProvider
+public class NoAuthenticationProvider : ITransformerBeeAuthenticationProvider
 {
     public bool UseAuthentication() => false;
 

From ec7deb8033b54fd86270a134aaf4040d6a6e784e Mon Sep 17 00:00:00 2001
From: konstantin <konstantin.klein@hochfrequenz.de>
Date: Thu, 1 Feb 2024 19:49:20 +0000
Subject: [PATCH 06/13] reanme

---
 ...nProvider.cs => ClientIdClientSecretAuthenticationProvider.cs} | 0
 1 file changed, 0 insertions(+), 0 deletions(-)
 rename TransformerBeeClient/TransformerBeeClient/{ClientIdClientSecretTokenProvider.cs => ClientIdClientSecretAuthenticationProvider.cs} (100%)

diff --git a/TransformerBeeClient/TransformerBeeClient/ClientIdClientSecretTokenProvider.cs b/TransformerBeeClient/TransformerBeeClient/ClientIdClientSecretAuthenticationProvider.cs
similarity index 100%
rename from TransformerBeeClient/TransformerBeeClient/ClientIdClientSecretTokenProvider.cs
rename to TransformerBeeClient/TransformerBeeClient/ClientIdClientSecretAuthenticationProvider.cs

From 8704eea67fe68f358b8c6c0148ed4028144d70de Mon Sep 17 00:00:00 2001
From: konstantin <konstantin.klein@hochfrequenz.de>
Date: Thu, 1 Feb 2024 19:52:32 +0000
Subject: [PATCH 07/13] more docs

---
 README.md | 20 +++++++++++++++-----
 1 file changed, 15 insertions(+), 5 deletions(-)

diff --git a/README.md b/README.md
index cbad941..694c6ac 100644
--- a/README.md
+++ b/README.md
@@ -22,14 +22,24 @@ Install it from nuget [TransformerBeeClient](https://www.nuget.org/packages/Tran
 dotnet add package TransformerBeeClient
 ```
 
-### Use it in your code
+### Authentication
+You need to provide something that implements `ITransformerBeeAuthenticationProvider` to the `TransformerBeeClient`.
 
-#### Authentication
-You need to provide something that implements `ITransformerBeeAuthenticator` to the `TransformerBeeClient`.
-If you're hosting transformer.bee in the same network and there is no authentication, you can use the `NoAuthenticationProvider` class.
+#### No Authentication
+If you're hosting transformer.bee in the same network and there is no authentication, you can use the `NoAuthenticationProvider`.
+```csharp
+using TransformerBeeClient;
+var myAuthenticator = new NoAuthenticationProvider();
+```
 
-Then, you can use the client like this:
+#### OAuth2 Client and Secret
+If, which is more likely, Hochfrequenz provided you with a client ID and secret, you can use the `ClientIdClientSecretAuthenticationProvider` class like this:
+```csharp
+using TransformerBeeClient;
+var myAuthenticator = new ClientIdClientSecretAuthenticationProvider("YOUR_CLIENT_ID", "YOUR_CLIENT_SECRET");
+```
 
+...todo
 ```csharp
 
 ```

From 417c28e7e2f6e11e70a1a8e390a22f3c27507197 Mon Sep 17 00:00:00 2001
From: konstantin <konstantin.klein@hochfrequenz.de>
Date: Thu, 1 Feb 2024 20:03:14 +0000
Subject: [PATCH 08/13] try?

---
 .github/workflows/integrationtests.yml        |  7 ++++
 .../EdifactToBo4eTests.cs                     | 31 +++++++++++++++++
 .../GithubActionClientFixture.cs              | 34 +++++++++++++++++++
 3 files changed, 72 insertions(+)
 create mode 100644 TransformerBeeClient/TransformerBeeClient.IntegrationTest/GithubActionClientFixture.cs

diff --git a/.github/workflows/integrationtests.yml b/.github/workflows/integrationtests.yml
index 6c1d5ab..3be05e3 100644
--- a/.github/workflows/integrationtests.yml
+++ b/.github/workflows/integrationtests.yml
@@ -48,3 +48,10 @@ jobs:
         working-directory: TransformerBeeClient/TransformerBeeClient.IntegrationTest
         run: |
           dotnet test
+      - name: Run Integration Tests (against real service)
+        working-directory: TransformerBeeClient/TransformerBeeClient.IntegrationTest
+        env:
+          CLIENT_ID: ${{ secrets.AUTH0_TEST_CLIENT_ID }}
+          CLIENT_SECRET: ${{ secrets.AUTH0_TEST_CLIENT_SECRET }}
+        run: |
+          dotnet test
diff --git a/TransformerBeeClient/TransformerBeeClient.IntegrationTest/EdifactToBo4eTests.cs b/TransformerBeeClient/TransformerBeeClient.IntegrationTest/EdifactToBo4eTests.cs
index 741041f..9767bdd 100644
--- a/TransformerBeeClient/TransformerBeeClient.IntegrationTest/EdifactToBo4eTests.cs
+++ b/TransformerBeeClient/TransformerBeeClient.IntegrationTest/EdifactToBo4eTests.cs
@@ -31,3 +31,34 @@ public async Task Edifact_Can_Be_Converted_To_Bo4e()
         result.Single().Transaktionen.Should().NotBeNullOrEmpty();
     }
 }
+
+/// <summary>
+/// those tests only run if the environment variables are set up correctly
+/// </summary>
+public class EdifactToBo4eTestsWithAuthentication : IClassFixture<GithubActionClientFixture>
+{
+    private readonly GithubActionClientFixture _client;
+
+    private readonly ITransformerBeeAuthenticationProvider? _authenticationProvider;
+
+    public EdifactToBo4eTestsWithAuthentication(GithubActionClientFixture clientFixture)
+    {
+        _client = clientFixture;
+        _authenticationProvider = clientFixture.AuthenticationProvider;
+    }
+
+    [Fact]
+    public async Task Edifact_Can_Be_Converted_To_Bo4e_With_Authentication()
+    {
+        if (_authenticationProvider is null)
+        {
+            return; // skip the test if no authentication provider is available
+        }
+        var httpClientFactory = _client.HttpClientFactory;
+        ICanConvertToBo4e client = new TransformerBeeRestClient(httpClientFactory, _authenticationProvider);
+        var edifactString = await File.ReadAllTextAsync("TestEdifacts/FV2310/55001.edi");
+        var result = await client.ConvertToBo4e(edifactString, EdifactFormatVersion.FV2310);
+        result.Should().BeOfType<List<Marktnachricht>>();
+        result.Single().Transaktionen.Should().NotBeNullOrEmpty();
+    }
+}
diff --git a/TransformerBeeClient/TransformerBeeClient.IntegrationTest/GithubActionClientFixture.cs b/TransformerBeeClient/TransformerBeeClient.IntegrationTest/GithubActionClientFixture.cs
new file mode 100644
index 0000000..58260e9
--- /dev/null
+++ b/TransformerBeeClient/TransformerBeeClient.IntegrationTest/GithubActionClientFixture.cs
@@ -0,0 +1,34 @@
+using Microsoft.Extensions.DependencyInjection;
+using Xunit;
+
+namespace TransformerBeeClient.IntegrationTest;
+
+/// <summary>
+/// A fixture that sets up the http client factory and an injectable service collection.
+/// It's thought to be used in the Github action.
+/// </summary>
+public class GithubActionClientFixture : IClassFixture<GithubActionClientFixture>
+{
+    public readonly IHttpClientFactory? HttpClientFactory;
+
+    public readonly ServiceCollection? ServiceCollection;
+
+    public readonly ITransformerBeeAuthenticationProvider? AuthenticationProvider;
+
+    public GithubActionClientFixture()
+    {
+        var clientId = Environment.GetEnvironmentVariable("CLIENT_ID");
+        var clientSecret = Environment.GetEnvironmentVariable("CLIENT_SECRET");
+        if (string.IsNullOrWhiteSpace(clientId) || string.IsNullOrWhiteSpace(clientSecret))
+        {
+            return;
+        }
+
+        var services = new ServiceCollection();
+        services.AddHttpClient("TransformerBee", client => { client.BaseAddress = new Uri("http://transformerstage.utilibee.io"); });
+        var serviceProvider = services.BuildServiceProvider();
+        ServiceCollection = services;
+        HttpClientFactory = serviceProvider.GetService<IHttpClientFactory>();
+        AuthenticationProvider = new ClientIdClientSecretAuthenticationProvider(clientId: clientId, clientSecret: clientSecret);
+    }
+}

From ac42692fe617cb478f111abe45a96830298e2b19 Mon Sep 17 00:00:00 2001
From: konstantin <konstantin.klein@hochfrequenz.de>
Date: Thu, 1 Feb 2024 20:06:26 +0000
Subject: [PATCH 09/13] so?

---
 .../TransformerBeeClient.IntegrationTest/EdifactToBo4eTests.cs | 3 ++-
 .../GithubActionClientFixture.cs                               | 1 +
 2 files changed, 3 insertions(+), 1 deletion(-)

diff --git a/TransformerBeeClient/TransformerBeeClient.IntegrationTest/EdifactToBo4eTests.cs b/TransformerBeeClient/TransformerBeeClient.IntegrationTest/EdifactToBo4eTests.cs
index 9767bdd..4180ec8 100644
--- a/TransformerBeeClient/TransformerBeeClient.IntegrationTest/EdifactToBo4eTests.cs
+++ b/TransformerBeeClient/TransformerBeeClient.IntegrationTest/EdifactToBo4eTests.cs
@@ -52,7 +52,8 @@ public async Task Edifact_Can_Be_Converted_To_Bo4e_With_Authentication()
     {
         if (_authenticationProvider is null)
         {
-            return; // skip the test if no authentication provider is available
+            await Console.Out.WriteLineAsync("Skipping tests because no client id or client secret is available");
+            return;
         }
         var httpClientFactory = _client.HttpClientFactory;
         ICanConvertToBo4e client = new TransformerBeeRestClient(httpClientFactory, _authenticationProvider);
diff --git a/TransformerBeeClient/TransformerBeeClient.IntegrationTest/GithubActionClientFixture.cs b/TransformerBeeClient/TransformerBeeClient.IntegrationTest/GithubActionClientFixture.cs
index 58260e9..3dedfa8 100644
--- a/TransformerBeeClient/TransformerBeeClient.IntegrationTest/GithubActionClientFixture.cs
+++ b/TransformerBeeClient/TransformerBeeClient.IntegrationTest/GithubActionClientFixture.cs
@@ -21,6 +21,7 @@ public GithubActionClientFixture()
         var clientSecret = Environment.GetEnvironmentVariable("CLIENT_SECRET");
         if (string.IsNullOrWhiteSpace(clientId) || string.IsNullOrWhiteSpace(clientSecret))
         {
+            Console.Out.WriteLine("Skipping tests because no client id or client secret is available");
             return;
         }
 

From 39ae8c6fb837da9c9bc6b7faa36c0da962c530e9 Mon Sep 17 00:00:00 2001
From: konstantin <konstantin.klein@hochfrequenz.de>
Date: Thu, 1 Feb 2024 20:07:00 +0000
Subject: [PATCH 10/13] s

---
 .../TransformerBeeClient.IntegrationTest/EdifactToBo4eTests.cs   | 1 +
 1 file changed, 1 insertion(+)

diff --git a/TransformerBeeClient/TransformerBeeClient.IntegrationTest/EdifactToBo4eTests.cs b/TransformerBeeClient/TransformerBeeClient.IntegrationTest/EdifactToBo4eTests.cs
index 4180ec8..2cdbce3 100644
--- a/TransformerBeeClient/TransformerBeeClient.IntegrationTest/EdifactToBo4eTests.cs
+++ b/TransformerBeeClient/TransformerBeeClient.IntegrationTest/EdifactToBo4eTests.cs
@@ -61,5 +61,6 @@ public async Task Edifact_Can_Be_Converted_To_Bo4e_With_Authentication()
         var result = await client.ConvertToBo4e(edifactString, EdifactFormatVersion.FV2310);
         result.Should().BeOfType<List<Marktnachricht>>();
         result.Single().Transaktionen.Should().NotBeNullOrEmpty();
+        await Console.Out.WriteLineAsync("Successfully converted edifact to bo4e - with authentication!");
     }
 }

From a6f80a35e39a071cace4b16e6db4d4f0beb1ae55 Mon Sep 17 00:00:00 2001
From: konstantin <konstantin.klein@hochfrequenz.de>
Date: Fri, 2 Feb 2024 06:53:33 +0000
Subject: [PATCH 11/13] better

---
 .../Bo4eToEdifactTests.cs                     |  6 ++---
 .../ClientFixture.cs                          |  4 ++--
 .../ConnectionTests.cs                        |  8 +++----
 .../EdifactToBo4eTests.cs                     | 22 +++++++++++--------
 .../GithubActionClientFixture.cs              |  8 +++----
 ...ransformerBeeClient.IntegrationTest.csproj |  1 +
 .../ConnectionTests.cs                        |  2 +-
 ...entIdClientSecretAuthenticationProvider.cs | 12 +++++-----
 .../TransformerBeeClient/Interfaces.cs        |  4 ++--
 .../NoAuthenticationProvider.cs               |  6 ++---
 .../TransformerBeeClient/RestClient.cs        | 20 ++++++++---------
 11 files changed, 48 insertions(+), 45 deletions(-)

diff --git a/TransformerBeeClient/TransformerBeeClient.IntegrationTest/Bo4eToEdifactTests.cs b/TransformerBeeClient/TransformerBeeClient.IntegrationTest/Bo4eToEdifactTests.cs
index a16767a..deb5f23 100644
--- a/TransformerBeeClient/TransformerBeeClient.IntegrationTest/Bo4eToEdifactTests.cs
+++ b/TransformerBeeClient/TransformerBeeClient.IntegrationTest/Bo4eToEdifactTests.cs
@@ -13,19 +13,19 @@ namespace TransformerBeeClient.IntegrationTest;
 public class Bo4eToEdifactTests : IClassFixture<ClientFixture>
 {
     private readonly ClientFixture _client;
-    private readonly ITransformerBeeAuthenticationProvider _authenticationProvider;
+    private readonly ITransformerBeeAuthenticator _authenticator;
 
     public Bo4eToEdifactTests(ClientFixture clientFixture)
     {
         _client = clientFixture;
-        _authenticationProvider = clientFixture.AuthenticationProvider;
+        _authenticator = clientFixture.Authenticator;
     }
 
     [Fact]
     public async Task BOneyComb_Can_Be_Converted_To_Edifact()
     {
         var httpClientFactory = _client.HttpClientFactory;
-        ICanConvertToEdifact client = new TransformerBeeRestClient(httpClientFactory, _authenticationProvider);
+        ICanConvertToEdifact client = new TransformerBeeRestClient(httpClientFactory, _authenticator);
         var boneyCombString = await File.ReadAllTextAsync("TestEdifacts/FV2310/55001.json");
         var deserializerOptions = new JsonSerializerOptions
         {
diff --git a/TransformerBeeClient/TransformerBeeClient.IntegrationTest/ClientFixture.cs b/TransformerBeeClient/TransformerBeeClient.IntegrationTest/ClientFixture.cs
index 9223881..1dec46b 100644
--- a/TransformerBeeClient/TransformerBeeClient.IntegrationTest/ClientFixture.cs
+++ b/TransformerBeeClient/TransformerBeeClient.IntegrationTest/ClientFixture.cs
@@ -12,7 +12,7 @@ public class ClientFixture : IClassFixture<ClientFixture>
 
     public readonly ServiceCollection ServiceCollection;
 
-    public readonly ITransformerBeeAuthenticationProvider AuthenticationProvider;
+    public readonly ITransformerBeeAuthenticator Authenticator;
 
     public ClientFixture()
     {
@@ -24,6 +24,6 @@ public ClientFixture()
         var serviceProvider = services.BuildServiceProvider();
         ServiceCollection = services;
         HttpClientFactory = serviceProvider.GetService<IHttpClientFactory>();
-        AuthenticationProvider = new NoAuthenticationProvider(); // easy for integration tests with transformer.bee running in docker
+        Authenticator = new NoAuthenticator(); // easy for integration tests with transformer.bee running in docker
     }
 }
diff --git a/TransformerBeeClient/TransformerBeeClient.IntegrationTest/ConnectionTests.cs b/TransformerBeeClient/TransformerBeeClient.IntegrationTest/ConnectionTests.cs
index f2d2030..bdc0f28 100644
--- a/TransformerBeeClient/TransformerBeeClient.IntegrationTest/ConnectionTests.cs
+++ b/TransformerBeeClient/TransformerBeeClient.IntegrationTest/ConnectionTests.cs
@@ -11,19 +11,19 @@ public class ConnectionTests : IClassFixture<ClientFixture>
 {
 
     private readonly ClientFixture _client;
-    private readonly ITransformerBeeAuthenticationProvider _authenticationProvider;
+    private readonly ITransformerBeeAuthenticator _authenticator;
 
     public ConnectionTests(ClientFixture clientFixture)
     {
         _client = clientFixture;
-        _authenticationProvider = clientFixture.AuthenticationProvider;
+        _authenticator = clientFixture.Authenticator;
     }
 
     [Fact]
     public async Task IsAvailable_Returns_True_If_Service_Is_Available()
     {
         var httpClientFactory = _client.HttpClientFactory;
-        var client = new TransformerBeeRestClient(httpClientFactory, _authenticationProvider);
+        var client = new TransformerBeeRestClient(httpClientFactory, _authenticator);
         var result = await client.IsAvailable();
         result.Should().BeTrue();
     }
@@ -37,7 +37,7 @@ public async Task IsAvailable_Throws_Exception_If_Host_Is_Unavailable()
             client.BaseAddress = new Uri("http://localhost:1234"); // <-- no service running under this address
         });
         var serviceProvider = services.BuildServiceProvider();
-        var client = new TransformerBeeRestClient(serviceProvider.GetService<IHttpClientFactory>(), _authenticationProvider);
+        var client = new TransformerBeeRestClient(serviceProvider.GetService<IHttpClientFactory>(), _authenticator);
         var checkIfIsAvailable = async () => await client.IsAvailable();
         await checkIfIsAvailable.Should().ThrowAsync<HttpRequestException>();
     }
diff --git a/TransformerBeeClient/TransformerBeeClient.IntegrationTest/EdifactToBo4eTests.cs b/TransformerBeeClient/TransformerBeeClient.IntegrationTest/EdifactToBo4eTests.cs
index 2cdbce3..b1c599a 100644
--- a/TransformerBeeClient/TransformerBeeClient.IntegrationTest/EdifactToBo4eTests.cs
+++ b/TransformerBeeClient/TransformerBeeClient.IntegrationTest/EdifactToBo4eTests.cs
@@ -2,6 +2,7 @@
 using FluentAssertions;
 using TransformerBeeClient.Model;
 using Xunit;
+using Xunit.Abstractions;
 
 namespace TransformerBeeClient.IntegrationTest;
 
@@ -12,19 +13,19 @@ public class EdifactToBo4eTests : IClassFixture<ClientFixture>
 {
     private readonly ClientFixture _client;
 
-    private readonly ITransformerBeeAuthenticationProvider _authenticationProvider;
+    private readonly ITransformerBeeAuthenticator _authenticator;
 
     public EdifactToBo4eTests(ClientFixture clientFixture)
     {
         _client = clientFixture;
-        _authenticationProvider = clientFixture.AuthenticationProvider;
+        _authenticator = clientFixture.Authenticator;
     }
 
     [Fact]
     public async Task Edifact_Can_Be_Converted_To_Bo4e()
     {
         var httpClientFactory = _client.HttpClientFactory;
-        ICanConvertToBo4e client = new TransformerBeeRestClient(httpClientFactory, _authenticationProvider);
+        ICanConvertToBo4e client = new TransformerBeeRestClient(httpClientFactory, _authenticator);
         var edifactString = await File.ReadAllTextAsync("TestEdifacts/FV2310/55001.edi");
         var result = await client.ConvertToBo4e(edifactString, EdifactFormatVersion.FV2310);
         result.Should().BeOfType<List<Marktnachricht>>();
@@ -39,28 +40,31 @@ public class EdifactToBo4eTestsWithAuthentication : IClassFixture<GithubActionCl
 {
     private readonly GithubActionClientFixture _client;
 
-    private readonly ITransformerBeeAuthenticationProvider? _authenticationProvider;
+    private readonly ITransformerBeeAuthenticator? _authenticationProvider;
 
-    public EdifactToBo4eTestsWithAuthentication(GithubActionClientFixture clientFixture)
+    ITestOutputHelper _output;
+
+    public EdifactToBo4eTestsWithAuthentication(GithubActionClientFixture clientFixture, ITestOutputHelper output)
     {
         _client = clientFixture;
         _authenticationProvider = clientFixture.AuthenticationProvider;
+        _output = output;
     }
 
-    [Fact]
+    [SkippableFact]
     public async Task Edifact_Can_Be_Converted_To_Bo4e_With_Authentication()
     {
         if (_authenticationProvider is null)
         {
-            await Console.Out.WriteLineAsync("Skipping tests because no client id or client secret is available");
-            return;
+            _output.WriteLine("Skipping test because no authentication provider is available");
         }
+        Skip.If(_authenticationProvider is null, "No authentication provider available");
         var httpClientFactory = _client.HttpClientFactory;
         ICanConvertToBo4e client = new TransformerBeeRestClient(httpClientFactory, _authenticationProvider);
         var edifactString = await File.ReadAllTextAsync("TestEdifacts/FV2310/55001.edi");
         var result = await client.ConvertToBo4e(edifactString, EdifactFormatVersion.FV2310);
         result.Should().BeOfType<List<Marktnachricht>>();
         result.Single().Transaktionen.Should().NotBeNullOrEmpty();
-        await Console.Out.WriteLineAsync("Successfully converted edifact to bo4e - with authentication!");
+        _output.WriteLine("Successfully converted edifact to bo4e - with authentication!");
     }
 }
diff --git a/TransformerBeeClient/TransformerBeeClient.IntegrationTest/GithubActionClientFixture.cs b/TransformerBeeClient/TransformerBeeClient.IntegrationTest/GithubActionClientFixture.cs
index 3dedfa8..0f8fb79 100644
--- a/TransformerBeeClient/TransformerBeeClient.IntegrationTest/GithubActionClientFixture.cs
+++ b/TransformerBeeClient/TransformerBeeClient.IntegrationTest/GithubActionClientFixture.cs
@@ -13,23 +13,21 @@ public class GithubActionClientFixture : IClassFixture<GithubActionClientFixture
 
     public readonly ServiceCollection? ServiceCollection;
 
-    public readonly ITransformerBeeAuthenticationProvider? AuthenticationProvider;
+    public readonly ITransformerBeeAuthenticator? AuthenticationProvider;
 
     public GithubActionClientFixture()
     {
         var clientId = Environment.GetEnvironmentVariable("CLIENT_ID");
         var clientSecret = Environment.GetEnvironmentVariable("CLIENT_SECRET");
-        if (string.IsNullOrWhiteSpace(clientId) || string.IsNullOrWhiteSpace(clientSecret))
+        if (clientSecret is null && clientId is null)
         {
-            Console.Out.WriteLine("Skipping tests because no client id or client secret is available");
             return;
         }
-
         var services = new ServiceCollection();
         services.AddHttpClient("TransformerBee", client => { client.BaseAddress = new Uri("http://transformerstage.utilibee.io"); });
         var serviceProvider = services.BuildServiceProvider();
         ServiceCollection = services;
         HttpClientFactory = serviceProvider.GetService<IHttpClientFactory>();
-        AuthenticationProvider = new ClientIdClientSecretAuthenticationProvider(clientId: clientId, clientSecret: clientSecret);
+        AuthenticationProvider = new ClientIdClientSecretAuthenticator(clientId: clientId, clientSecret: clientSecret);
     }
 }
diff --git a/TransformerBeeClient/TransformerBeeClient.IntegrationTest/TransformerBeeClient.IntegrationTest.csproj b/TransformerBeeClient/TransformerBeeClient.IntegrationTest/TransformerBeeClient.IntegrationTest.csproj
index 8b85110..a43ba73 100644
--- a/TransformerBeeClient/TransformerBeeClient.IntegrationTest/TransformerBeeClient.IntegrationTest.csproj
+++ b/TransformerBeeClient/TransformerBeeClient.IntegrationTest/TransformerBeeClient.IntegrationTest.csproj
@@ -14,6 +14,7 @@
         <PackageReference Include="Microsoft.NET.Test.Sdk" Version="17.6.0" />
         <PackageReference Include="coverlet.collector" Version="6.0.0" />
         <PackageReference Include="xunit" Version="2.6.6" />
+        <PackageReference Include="Xunit.SkippableFact" Version="1.4.13" />
     </ItemGroup>
 
     <ItemGroup>
diff --git a/TransformerBeeClient/TransformerBeeClient.UnitTest/ConnectionTests.cs b/TransformerBeeClient/TransformerBeeClient.UnitTest/ConnectionTests.cs
index 8614bf9..ae92893 100644
--- a/TransformerBeeClient/TransformerBeeClient.UnitTest/ConnectionTests.cs
+++ b/TransformerBeeClient/TransformerBeeClient.UnitTest/ConnectionTests.cs
@@ -15,7 +15,7 @@ public void IsAvailable_Throws_ArgumentNullException_If_BaseAddress_Is_Not_Confi
             client.BaseAddress = null;
         });
         var serviceProvider = services.BuildServiceProvider();
-        var instantiateClient = () => new TransformerBeeRestClient(serviceProvider.GetService<IHttpClientFactory>(), new NoAuthenticationProvider());
+        var instantiateClient = () => new TransformerBeeRestClient(serviceProvider.GetService<IHttpClientFactory>(), new NoAuthenticator());
         instantiateClient.Should().Throw<ArgumentNullException>();
     }
 }
diff --git a/TransformerBeeClient/TransformerBeeClient/ClientIdClientSecretAuthenticationProvider.cs b/TransformerBeeClient/TransformerBeeClient/ClientIdClientSecretAuthenticationProvider.cs
index a8aa9f4..43845dd 100644
--- a/TransformerBeeClient/TransformerBeeClient/ClientIdClientSecretAuthenticationProvider.cs
+++ b/TransformerBeeClient/TransformerBeeClient/ClientIdClientSecretAuthenticationProvider.cs
@@ -5,9 +5,9 @@ namespace TransformerBeeClient;
 using System.IdentityModel.Tokens.Jwt;
 
 /// <summary>
-/// a <see cref="ITransformerBeeAuthenticationProvider"/> that is based on a client secret and a client id
+/// a <see cref="ITransformerBeeAuthenticator"/> that is based on a client secret and a client id
 /// </summary>
-public class ClientIdClientSecretAuthenticationProvider : ITransformerBeeAuthenticationProvider
+public class ClientIdClientSecretAuthenticator : ITransformerBeeAuthenticator
 {
     protected const string Auth0Domain = "https://hochfrequenz.eu.auth0.com";
     protected const string TransformerBeeScope = "client:default";
@@ -27,7 +27,7 @@ public class ClientIdClientSecretAuthenticationProvider : ITransformerBeeAuthent
     private readonly bool _useAuthentication;
 
     /// <summary>
-    /// <inheritdoc cref="ITransformerBeeAuthenticationProvider.UseAuthentication"/>
+    /// <inheritdoc cref="ITransformerBeeAuthenticator.UseAuthentication"/>
     /// </summary>
     public bool UseAuthentication() => _useAuthentication;
 
@@ -36,10 +36,10 @@ public class ClientIdClientSecretAuthenticationProvider : ITransformerBeeAuthent
     /// </summary>
     private readonly SemaphoreSlim _tokenRequestSemaphore = new(1, 1);
 
-    /// <summary>A <see cref="ITransformerBeeAuthenticationProvider"/> that is based on a client secret and a client id</summary>
+    /// <summary>A <see cref="ITransformerBeeAuthenticator"/> that is based on a client secret and a client id</summary>
     /// <param name="clientId">OAuth2 client secret (ask Hochfrequenz)</param>
     /// <param name="clientSecret">OAuth2 client ID (ask Hochfrequenz)</param>
-    public ClientIdClientSecretAuthenticationProvider(string? clientId, string? clientSecret)
+    public ClientIdClientSecretAuthenticator(string? clientId, string? clientSecret)
     {
         if (!string.IsNullOrWhiteSpace(clientId) && string.IsNullOrWhiteSpace(clientSecret))
         {
@@ -97,7 +97,7 @@ private static async Task<DiscoveryDocumentResponse> GetDiscoveryDocument(HttpCl
     /// </summary>
     /// <returns>the token</returns>
     /// <exception cref="AuthenticationException">if something goes wrong</exception>
-    public async Task<string> GetTokenAsync(HttpClient client)
+    public async Task<string> Authenticate(HttpClient client)
     {
         using (_tokenRequestSemaphore)
         {
diff --git a/TransformerBeeClient/TransformerBeeClient/Interfaces.cs b/TransformerBeeClient/TransformerBeeClient/Interfaces.cs
index d74cae7..1dd9eaf 100644
--- a/TransformerBeeClient/TransformerBeeClient/Interfaces.cs
+++ b/TransformerBeeClient/TransformerBeeClient/Interfaces.cs
@@ -36,7 +36,7 @@ public interface ICanConvertToEdifact
 /// <summary>
 /// Can provide information on whether you need to authenticate against transformer.bee and how
 /// </summary>
-public interface ITransformerBeeAuthenticationProvider
+public interface ITransformerBeeAuthenticator
 {
     /// <summary>
     /// returns true iff the client should use authentication
@@ -48,5 +48,5 @@ public interface ITransformerBeeAuthenticationProvider
     /// provides the token to authenticate against transformer.bee (if and only if <see cref="UseAuthentication"/> is true)
     /// </summary>
     /// <returns></returns>
-    public Task<string> GetTokenAsync(HttpClient client);
+    public Task<string> Authenticate(HttpClient client);
 }
diff --git a/TransformerBeeClient/TransformerBeeClient/NoAuthenticationProvider.cs b/TransformerBeeClient/TransformerBeeClient/NoAuthenticationProvider.cs
index 3c97cde..fdf0e02 100644
--- a/TransformerBeeClient/TransformerBeeClient/NoAuthenticationProvider.cs
+++ b/TransformerBeeClient/TransformerBeeClient/NoAuthenticationProvider.cs
@@ -1,13 +1,13 @@
 namespace TransformerBeeClient;
 
 /// <summary>
-/// a <see cref="ITransformerBeeAuthenticationProvider"/> stub that just indicates, we don't need to authenticate against transformer.bee, because we're e.g. in the same network
+/// a <see cref="ITransformerBeeAuthenticator"/> stub that just indicates, we don't need to authenticate against transformer.bee, because we're e.g. in the same network
 /// </summary>
-public class NoAuthenticationProvider : ITransformerBeeAuthenticationProvider
+public class NoAuthenticator : ITransformerBeeAuthenticator
 {
     public bool UseAuthentication() => false;
 
-    public Task<string> GetTokenAsync(HttpClient client)
+    public Task<string> Authenticate(HttpClient client)
     {
         throw new NotImplementedException("This must never be called, because we don't use authentication.");
     }
diff --git a/TransformerBeeClient/TransformerBeeClient/RestClient.cs b/TransformerBeeClient/TransformerBeeClient/RestClient.cs
index d9a60df..3628e2b 100644
--- a/TransformerBeeClient/TransformerBeeClient/RestClient.cs
+++ b/TransformerBeeClient/TransformerBeeClient/RestClient.cs
@@ -14,7 +14,7 @@ namespace TransformerBeeClient;
 /// </summary>
 public class TransformerBeeRestClient : ICanConvertToBo4e, ICanConvertToEdifact
 {
-    private readonly ITransformerBeeAuthenticationProvider _authenticationProvider;
+    private readonly ITransformerBeeAuthenticator _authenticator;
     private readonly HttpClient _httpClient;
 
     private readonly JsonSerializerOptions _jsonSerializerOptions = new()
@@ -28,10 +28,10 @@ public class TransformerBeeRestClient : ICanConvertToBo4e, ICanConvertToEdifact
     /// It will create a client from said factory and use the <paramref name="httpClientName"/> for that.
     /// </summary>
     /// <param name="httpClientFactory">factory to create the http client from</param>
-    /// <param name="authenticationProvider">something that tells you whether and how you need to authenticate yourself at transformer.bee</param>
+    /// <param name="authenticator">something that tells you whether and how you need to authenticate yourself at transformer.bee</param>
     /// <param name="httpClientName">name used to create the client</param>
     /// <remarks>Find the OpenAPI Spec here: https://transformerstage.utilibee.io/swagger/index.html</remarks>
-    public TransformerBeeRestClient(IHttpClientFactory httpClientFactory, ITransformerBeeAuthenticationProvider authenticationProvider, string httpClientName = "TransformerBee")
+    public TransformerBeeRestClient(IHttpClientFactory httpClientFactory, ITransformerBeeAuthenticator authenticator, string httpClientName = "TransformerBee")
     {
         _httpClient = httpClientFactory.CreateClient(httpClientName);
         if (_httpClient.BaseAddress == null)
@@ -39,7 +39,7 @@ public TransformerBeeRestClient(IHttpClientFactory httpClientFactory, ITransform
             throw new ArgumentNullException(nameof(httpClientFactory), $"The http client factory must provide a base address for the client with name '{httpClientName}'");
         }
 
-        _authenticationProvider = authenticationProvider ?? throw new ArgumentNullException(nameof(authenticationProvider));
+        _authenticator = authenticator ?? throw new ArgumentNullException(nameof(authenticator));
     }
 
     /// <summary>
@@ -47,9 +47,9 @@ public TransformerBeeRestClient(IHttpClientFactory httpClientFactory, ITransform
     /// </summary>
     private async Task EnsureAuthentication()
     {
-        if (_authenticationProvider.UseAuthentication())
+        if (_authenticator.UseAuthentication())
         {
-            var token = await _authenticationProvider.GetTokenAsync(_httpClient);
+            var token = await _authenticator.Authenticate(_httpClient);
             _httpClient.DefaultRequestHeaders.Authorization = new AuthenticationHeaderValue("Bearer", token);
         }
     }
@@ -108,9 +108,9 @@ public async Task<List<Marktnachricht>> ConvertToBo4e(string edifact, EdifactFor
         var httpResponse = await _httpClient.PostAsync(convertUrl, new StringContent(requestJson, Encoding.UTF8, "application/json"));
         if (!httpResponse.IsSuccessStatusCode)
         {
-            if (httpResponse.StatusCode == HttpStatusCode.Unauthorized && !_authenticationProvider.UseAuthentication())
+            if (httpResponse.StatusCode == HttpStatusCode.Unauthorized && !_authenticator.UseAuthentication())
             {
-                throw new AuthenticationException($"Did you correctly set up the {nameof(ITransformerBeeAuthenticationProvider)}?");
+                throw new AuthenticationException($"Did you correctly set up the {nameof(ITransformerBeeAuthenticator)}?");
             }
 
             throw new HttpRequestException($"Could not convert {edifact} to BO4E. Status code: {httpResponse.StatusCode}");
@@ -149,9 +149,9 @@ public async Task<string> ConvertToEdifact(BOneyComb boneyComb, EdifactFormatVer
         var httpResponse = await _httpClient.PostAsync(convertUrl, new StringContent(requestJson, Encoding.UTF8, "application/json"));
         if (!httpResponse.IsSuccessStatusCode)
         {
-            if (httpResponse.StatusCode == HttpStatusCode.Unauthorized && !_authenticationProvider.UseAuthentication())
+            if (httpResponse.StatusCode == HttpStatusCode.Unauthorized && !_authenticator.UseAuthentication())
             {
-                throw new AuthenticationException($"Did you correctly set up the {nameof(ITransformerBeeAuthenticationProvider)}?");
+                throw new AuthenticationException($"Did you correctly set up the {nameof(ITransformerBeeAuthenticator)}?");
             }
 
             throw new HttpRequestException($"Could not convert to EDIFACT; Status code: {httpResponse.StatusCode}");

From 4c92dab98c8f631362a56d8f1607b9da99b744ce Mon Sep 17 00:00:00 2001
From: konstantin <konstantin.klein@hochfrequenz.de>
Date: Fri, 2 Feb 2024 06:54:41 +0000
Subject: [PATCH 12/13] rename

---
 ...enticationProvider.cs => ClientIdClientSecretAuthenticator.cs} | 0
 .../{NoAuthenticationProvider.cs => NoAutenticator.cs}            | 0
 2 files changed, 0 insertions(+), 0 deletions(-)
 rename TransformerBeeClient/TransformerBeeClient/{ClientIdClientSecretAuthenticationProvider.cs => ClientIdClientSecretAuthenticator.cs} (100%)
 rename TransformerBeeClient/TransformerBeeClient/{NoAuthenticationProvider.cs => NoAutenticator.cs} (100%)

diff --git a/TransformerBeeClient/TransformerBeeClient/ClientIdClientSecretAuthenticationProvider.cs b/TransformerBeeClient/TransformerBeeClient/ClientIdClientSecretAuthenticator.cs
similarity index 100%
rename from TransformerBeeClient/TransformerBeeClient/ClientIdClientSecretAuthenticationProvider.cs
rename to TransformerBeeClient/TransformerBeeClient/ClientIdClientSecretAuthenticator.cs
diff --git a/TransformerBeeClient/TransformerBeeClient/NoAuthenticationProvider.cs b/TransformerBeeClient/TransformerBeeClient/NoAutenticator.cs
similarity index 100%
rename from TransformerBeeClient/TransformerBeeClient/NoAuthenticationProvider.cs
rename to TransformerBeeClient/TransformerBeeClient/NoAutenticator.cs

From be5fb8adc50c371e51d8f90b45210ebba9c69880 Mon Sep 17 00:00:00 2001
From: konstantin <konstantin.klein@hochfrequenz.de>
Date: Fri, 2 Feb 2024 06:59:56 +0000
Subject: [PATCH 13/13] wip

---
 .github/dependabot.yml                                      | 2 +-
 .github/workflows/integrationtests.yml                      | 2 +-
 README.md                                                   | 6 +++---
 .../EdifactToBo4eTests.cs                                   | 1 +
 4 files changed, 6 insertions(+), 5 deletions(-)

diff --git a/.github/dependabot.yml b/.github/dependabot.yml
index f4dd377..8aa2465 100644
--- a/.github/dependabot.yml
+++ b/.github/dependabot.yml
@@ -6,7 +6,7 @@
 version: 2
 updates:
   - package-ecosystem: "nuget" # See documentation for possible values
-    directory: "/" # Location of package manifests
+    directory: "/TransformerBeeClient" # Location of package manifests
     schedule:
       interval: "weekly"
   # Maintain dependencies for GitHub Actions
diff --git a/.github/workflows/integrationtests.yml b/.github/workflows/integrationtests.yml
index 3be05e3..42b38b2 100644
--- a/.github/workflows/integrationtests.yml
+++ b/.github/workflows/integrationtests.yml
@@ -54,4 +54,4 @@ jobs:
           CLIENT_ID: ${{ secrets.AUTH0_TEST_CLIENT_ID }}
           CLIENT_SECRET: ${{ secrets.AUTH0_TEST_CLIENT_SECRET }}
         run: |
-          dotnet test
+          dotnet test --filter TestCollectionName='authenticated'
diff --git a/README.md b/README.md
index 694c6ac..11d651e 100644
--- a/README.md
+++ b/README.md
@@ -23,17 +23,17 @@ dotnet add package TransformerBeeClient
 ```
 
 ### Authentication
-You need to provide something that implements `ITransformerBeeAuthenticationProvider` to the `TransformerBeeClient`.
+You need to provide something that implements `ITransformerBeeAuthenticator` to the `TransformerBeeClient`.
 
 #### No Authentication
-If you're hosting transformer.bee in the same network and there is no authentication, you can use the `NoAuthenticationProvider`.
+If you're hosting transformer.bee in the same network and there is no authentication, you can use the `NoAuthenticator`.
 ```csharp
 using TransformerBeeClient;
 var myAuthenticator = new NoAuthenticationProvider();
 ```
 
 #### OAuth2 Client and Secret
-If, which is more likely, Hochfrequenz provided you with a client ID and secret, you can use the `ClientIdClientSecretAuthenticationProvider` class like this:
+If, which is more likely, Hochfrequenz provided you with a client ID and secret, you can use the `ClientIdClientSecretAuthenticator` class like this:
 ```csharp
 using TransformerBeeClient;
 var myAuthenticator = new ClientIdClientSecretAuthenticationProvider("YOUR_CLIENT_ID", "YOUR_CLIENT_SECRET");
diff --git a/TransformerBeeClient/TransformerBeeClient.IntegrationTest/EdifactToBo4eTests.cs b/TransformerBeeClient/TransformerBeeClient.IntegrationTest/EdifactToBo4eTests.cs
index b1c599a..690cb96 100644
--- a/TransformerBeeClient/TransformerBeeClient.IntegrationTest/EdifactToBo4eTests.cs
+++ b/TransformerBeeClient/TransformerBeeClient.IntegrationTest/EdifactToBo4eTests.cs
@@ -36,6 +36,7 @@ public async Task Edifact_Can_Be_Converted_To_Bo4e()
 /// <summary>
 /// those tests only run if the environment variables are set up correctly
 /// </summary>
+[Collection("authenticated")]
 public class EdifactToBo4eTestsWithAuthentication : IClassFixture<GithubActionClientFixture>
 {
     private readonly GithubActionClientFixture _client;