Pydantic validation error: Service.technologies doesn't accept None from API response

[osdakira]

Bug Report: Service.technologies field doesn't accept None value

Description

The Service model in the Python SDK has a validation error when the Instana API returns null for the technologies field. The model definition requires a List[str], but the API can return null for this field.

Location

File: instana_client/models/service.py
Line: 34
Repository: https://github.com/instana/client-python/blob/main/instana_client/models/service.py#L34

Current Implementation

technologies: List[StrictStr] = Field(description="List of technologies: `Eg:[\"springbootApplicationContainer\"]`")

Problem

When calling ApplicationAnalyzeApi.get_traces(), the API returns:

{
  "items": [
    {
      "trace": {
        "service": {
          "id": "...",
          "label": "...",
          "technologies": null,  // <-- This causes validation error
          "types": [],
          "snapshotIds": []
        }
      }
    }
  ]
}

This results in a Pydantic validation error:

pydantic_core._pydantic_core.ValidationError: 1 validation error for Service
technologies
  Input should be a valid list [type=list_type, input_value=None, input_type=NoneType]

Expected Behavior

The technologies field should accept None values since the API can return null.

Proposed Fix

Change line 34 in service.py from:

technologies: List[StrictStr] = Field(description="List of technologies: `Eg:[\"springbootApplicationContainer\"]`")

To:

technologies: Optional[List[StrictStr]] = Field(default=None, description="List of technologies: `Eg:[\"springbootApplicationContainer\"]`")

Reproduction Steps

1. Verify API returns null for technologies field

# Set your Instana credentials
export INSTANA_BASE_URL="https://your-tenant.instana.io"
export INSTANA_API_TOKEN="your-api-token"

# Call the API directly
curl -X POST "${INSTANA_BASE_URL}/api/application-monitoring/analyze/traces" \
  -H "Authorization: apiToken ${INSTANA_API_TOKEN}" \
  -H "Content-Type: application/json" \
  -d '{"pagination": {"retrievalSize": 1}}' \
  | jq '.items[0].trace.service | {id, label, technologies, types}'

Expected output:

{
  "id": "fdf10867224d2bc8915b021527cec356c46fe78e",
  "label": "your-service-name",
  "technologies": null,
  "types": []
}

This proves the API returns null for the technologies field.

2. Try to use the SDK

from instana_client.api.application_analyze_api import ApplicationAnalyzeApi
from instana_client.configuration import Configuration
from instana_client.api_client import ApiClient
from instana_client.models.get_traces import GetTraces
import os

config = Configuration()
config.host = os.getenv('INSTANA_BASE_URL')
config.api_key['ApiKeyAuth'] = os.getenv('INSTANA_API_TOKEN')
config.api_key_prefix['ApiKeyAuth'] = 'apiToken'

api_client = ApiClient(config)
api = ApplicationAnalyzeApi(api_client)

# This will fail with Pydantic validation error
result = api.get_traces(get_traces=GetTraces())

Error:

pydantic_core._pydantic_core.ValidationError: 1 validation error for Service
technologies
  Input should be a valid list [type=list_type, input_value=None, input_type=NoneType]

Environment

• SDK Version: 1.309.1268 (based on OpenAPI Generator output)
• Python Version: 3.13
• Pydantic Version: 2.x