feat(content-blog): add full blog post html into RSS/Atom feeds

[moonrailgun]

Motivation

RSS Reader should get full content

Have you read the Contributing Guidelines on pull requests?

YEP

Test Plan

Just take a look of website rss xml file. and check item content

Further Plan

If accept this pr, i know my way is right and i will try to translate origin mdx to html, for make rss user have better experiences.

Related PRs

(If this PR adds or changes functionality, please take some time to update the docs at https://github.com/facebook/docusaurus, and link to your PR here.)

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[github-actions]

Size Change: -46 B (0%)

Total Size: 532 kB

Filename	Size	Change
website/build/assets/css/styles.********.css	87.1 kB	-46 B (0%)

ℹ️ View Unchanged

Filename	Size	Change
website/build/assets/js/main.********.js	359 kB	0 B
website/build/blog/2017/12/14/introducing-docusaurus/index.html	60.3 kB	0 B
website/build/docs/introduction/index.html	235 B	0 B
website/build/index.html	25.4 kB	0 B

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[slorber]

Thanks for this PR, this has been requested here already: #3719

Your implementation is not correct because it assume the blog post content is a simple string, which is not the case in practice as we use MDX

Read my comment here. on how you could transform an MDX string to an HTML string:

#3719 (comment)

[github-actions]

⚡️ Lighthouse report for the changes in this PR:

Category	Score
🟢 Performance	100
🟠 Accessibility	72
🟢 Best practices	93
🟠 SEO	50
🟠 PWA	55

Lighthouse ran on https://deploy-preview-4330--docusaurus-2.netlify.app/

[moonrailgun]

Hi @slorber , Thanks for your review and reply.

First commit is just backup to ensure the full blog rss content is expected behaviour

I update content generate logic to make sure rss reader can get a readable, plain html string. So i remove import statement with remark-mdx-remove-imports, although this package marked as Deprecated but its still have a nice work.

And update testcase to ensure bigger cover range.

Before:

After:

[moonrailgun]

Is any other problem for this pr?

[MatanBobi]

I update content generate logic to make sure rss reader can get a readable, plain html string. So i remove import statement with remark-mdx-remove-imports, although this package marked as Deprecated but its still have a nice work.

I'm not sure I understand why we need remark-mdx-remove-imports, can you please explain? :)
Also, if that package is considered deprecated, IMO we should not use it because if it will have bugs, there won't be any support and we won't be able to fix those.

Regarding the PR, I'm pretty sure React and React-DOM should be defined as peerDependencies and not dependencies. Also, I think the mdx-runtime functionality should be a part of mdx-loader and not the docusaurus-utils package.

CC: @slorber

[moonrailgun]

I'm not sure I understand why we need remark-mdx-remove-imports, can you please explain? :)

because rss content should be a plain html, and in most custom component, its have their own javascript logic.

Its will not a nice work in feed reader.

Its just my mind

[moonrailgun]

Regarding the PR, I'm pretty sure React and React-DOM should be defined as peerDependencies and not dependencies. Also, I think the mdx-runtime functionality should be a part of mdx-loader and not the docusaurus-utils package.

Hi @MatanBobi , thanks for your review, i am move those into peerDependencies, its my mistake.

And for mdx-loader, this package worked as a webpack loader, how can i use in feed generate? I have no idea about it. Could you explain more about your idea?

[slorber]

Hey.

After more tests, I'm finally merging this PR, as I think it is better than before and good enough for now.

Keep in mind that the RSS feed content has some limitations that I documented here: #5664

[moonrailgun]

Nice! Thanks for your code and time!

RSS feature is soooo awesome for a RSS reader!

[slorber]

Note, if you use require() calls in your mdx blog posts, your site build will fail and it is annoying for some users.

In #5753 I temporarily swallow such errors, so if you have a blog post that doesn't render fully in the feed, it means there's an issue and we couldn't render it.

See also #5664 for explainations