[WIP] Gatsby migration

[iAdramelk]

ToDo:

• Install Gatsby.
• Remove Next.js.
• Move _document.js content to html.js and SEO files.
• Rewrite LocalLink to use gatsby-link.
• Update GA to work with new setup.
• Move sentry from _app.js to gatsby plugin.
• Set up styled-components SSR in gatsby.
• Move static pages to gatsby (index, features, support, community).
• Replace CDN urls for css and js assets in head with normal imports.
• Docs page
  • Basic render
  • Sidebar
    • Make standard pages work
    • Make source: false menu items work (update logic for normalizedSidebar generation)
  • Right menu
    • Headers with ids
    • Custom ids in headers
    • Move headings extraction to backend
  • External link icons
  • Prism syntaxes
    • Port custom syntax for dvc from blog
    • Convert custom syntax for usage
    • Find existing syntax for vim
  • Convert dvc commands to links
  • Custom React components for details and abbr
• Set up redirects.
• Set up API endpoints.

[shcheklein]

@fabiosantoscode could start reviewing this? )

[fabiosantoscode]

Lookin' good! Just a few comments. Also for the API/redirects to work locally and in production, have a look at: https://github.com/iterative/blog/pull/122/files. You just have to make the API and the redirects into express middleware, then mount it into an express server for production, and in the gatsby development server using gatsby-config.

[fabiosantoscode]

Aside: We can probably use something like sentry or crashlytics here. If we end up implementing it in another iterative property we can plop it here as well at no additional cost.

[iAdramelk]

This, or maybe switch to GTM and send it from there.

[fabiosantoscode]

This is a gargantuan amount of work, good luck @iAdramelk :)

[iAdramelk]

@fabiosantoscode I added AIP and reedirects middlewares + simple express server, can you please review them and advice on additional headers and other stuff that I maybe should add here?

[shcheklein]

@iAdramelk please rebase/merge, and let's check why CI is failing

[shcheklein]

• page titles do not update
• edit on Github does not work
• getting / related redirects - should be fixed probably the same way we fixed it for blog
• NEXT on https://dvc-landing-gatsby-migr-abefpq.herokuapp.com/doc/command-reference/version does not work

[jorgeorpinel]

Follow up on my previews review on #1025 (comment)

• The DOC link still seems to be hardcoded to /doc/get-started. What if we change the first doc in the future, e.g. to /doc/install, will the link change automatically?
• /doc path redirects to /doc/get-started. Again, what if we want to change the first doc to something else? Would we have to change the redirects file every time? Moving to nav: fix problem with non-existing pages in sidebar #1060
• And if we have to do this (instead of just loading the first doc and keeping the /doc path) maybe change the /docs and /documentation redirects that currently go to /doc, so they go directly to the first doc? (Also keeping /doc -> /doc/get-started some time for legacy 301 support)
• How can we test the subdomain redirects? (www, man, error, code/data/remote)
• URL path redirects e.g. /documentation/command-reference do not add the required trailing slash e.g. -> /doc/command-reference, which causes a 2nd redirect to the final location: /doc/command-reference/

[shcheklein]

/doc path redirects to /doc/get-started ... The DOC link still seems to be hardcoded to /doc/get-started

@jorgeorpinel there is a ticket to handle all of this after the merge - #1060 - please chime in here.

How can we test the subdomain redirects? (www, man, error, code/data/remote)

we will deploy and test them

which causes a 2nd redirect to the final location: /doc/command-reference/

will be handled when we merge dvc.org with blog the way I understand this cc @fabiosantoscode @iAdramelk @pavelgrinchenko

[iAdramelk]

@jorgeorpinel

/doc path redirects to /doc/get-started. Again, what if we want to change the first doc to something else? Would we have to change the redirects file every time?

It's actually not hardcoded now. It resolves to the first item with the source in the sidebar.json.

[jorgeorpinel]

It's actually not hardcoded now

I'm seeing it hardcoded in redirects-list.json @iAdramelk

[iAdramelk]

I'm seeing it hardcoded in redirects-list.json

It's hardcoded in redirects for now (to redirect users who hit urls from search engines or bookmarks), but actual links in html and site header/footer are not hardcoded. They are rosolved using sidebar.json.

But you are right, it's not an ideal situation and it can break if we change root sidebar.json right now without changing redirects.