trailingSlash has no effect on URLs on blog feeds

[ilarischeinin]

Have you read the Contributing Guidelines on issues?

• I have read the Contributing Guidelines on issues.

Prerequisites

• I'm using the latest version of Docusaurus.
• I have tried the npm run clear or yarn clear command.
• I have tried rm -rf node_modules yarn.lock package-lock.json and re-installing packages.
• I have tried creating a repro with https://new.docusaurus.io.
• I have read the console error message carefully (if applicable).

Description

My deployment (nginx-s3 ingress) requires trailing slashes, so I'm using trailingSlash: true. This works for URLs on the web pages, but the ones in blog feeds (RSS and Atom) do not get a trailing slash and therefore do not work.

Reproducible demo

No response

Steps to reproduce

# create a new site and build
npx create-docusaurus@latest reprex classic
cd reprex
npm run build

# links to an example blog post are without a trailing slash, both in index.html:
grep -o ".......blog/welcome.." build/blog/index.html
# href="/blog/welcome">
# href="/blog/welcome">

# and in the RSS and Atom feeds:
grep -o ".......blog/welcome.." build/blog/rss.xml
# te.com/blog/welcome</
grep -o ".......blog/welcome.." build/blog/atom.xml
# te.com/blog/welcome"/

# add 'trailingSlash: true' to the config and re-build
gsed -i '12 a\  trailingSlash: true,' docusaurus.config.js
npm run build

# now links in index.html are with the trailing slash:
grep -o ".......blog/welcome.." build/blog/index.html
# href="/blog/welcome/"
# href="/blog/welcome/"

# but the RSS and Atom feed ones are still without a trailing slash:
grep -o ".......blog/welcome.." build/blog/rss.xml
# te.com/blog/welcome</
grep -o ".......blog/welcome.." build/blog/atom.xml
# te.com/blog/welcome"/

Expected behavior

URLs on both the web pages and the feeds respect the trailingSlash setting.

Actual behavior

Web pages are affected by trailingSlash but feeds are not.

Your environment

• Docusaurus version used: 2.0.0-beta.21
• Environment name and version (e.g. Chrome 89, Node.js 16.4): Node v18.3.0
• Operating system and version (e.g. Ubuntu 20.04.2 LTS): macOS Big Sur 11.6.5

Self-service

• I'd be willing to fix this bug myself.

[Josh-Cena]

Interesting—yes, we need to normalize trailing slashes when generating metadata as well.

[slorber]

Hmmm yes we can see that on our own deploy previews:

https://deploy-preview-7644--docusaurus-2.netlify.app/blog/rss.xml

Interesting—yes, we need to normalize trailing slashes when generating metadata as well.

I wanted trailing slashes to be mostly handled automatically in core so that plugin authors do not have to care about it, so normally metadata do not necessarily need a trailing slash, but yes for the feed and sitemaps we should apply the trailing slash at the plugin level, and I forgot the blog feed 😅: we can probably do like in the sitemaps and apply at feed generation?

Not 100% sure we handle blog post feed base URL very well either, worth double-checking but the code looks wrong

[Josh-Cena]

we can probably do like in the sitemaps and apply at feed generation?

Yes, I think that's fine.

Not 100% sure we handle blog post feed base URL very well either

Looks correct to me? Do you mean https://docusaurus.io/tests/blog/rss.xml?

[slorber]

Looks correct to me? Do you mean docusaurus.io/tests/blog/rss.xml?

Yes I'm wrong 👍

link: normalizeUrl([siteUrl, permalink]) => forgot permalink contains the baseUrl already

[slorber]

already handled in #9920