Broken links and pages in elm-lang.org

[berndca]

I did some testing in the context of converting elm-lang.org to static pages. All tests were done using a local installation of the server.

There is a Debug.crash statement in pages:

• http://elm-lang.org/blog/announce/0.12
• http://elm-lang.org/blog/announce/0.12.3

The following internal links (http://elm-lang.org/...) are broken, i.e. the target does not exist.:

• /blog/escape-from-callback-hell
• /blog/announce/Workshop-2013.elm
• /examples/WebGL/Thwomp.elm
• /learn/Modules.elm
• /learn/Interactive-UI-Elements.elm
• /learn/JavaScript-Integration.elm
• /learn/Getting-started-with-Types.elm
• /Tango-Palette.png
• /edit/examples/Intermediate/Circles.elm
• /edit/examples/Elements/ToForm.elm
• /edit/examples/Elements/Sprite.elm
• /edit/examples/Elements/Typeface.elm
• /edit/examples/Intermediate/Slide.elm
• /edit/examples/Intermediate/ColorWheel.elm
• /Documentation.elm
• /edit/examples/Elements/Position.elm
• /edit/examples/Elements/Spacer.elm
• /edit/examples/JavaScript/ZipCodes.elm
• /Contribute.elm
• /edit/examples/Reactive/Draw.elm
• /edit/examples/Intermediate/Turtle.elm
• /edit/examples/Reactive/Touch.elm
• /edit/examples/Reactive/Taps.elm
• /edit/examples/Reactive/Touches.elm
• /edit/examples/Intermediate/Mario.elm
• /edit/examples/Intermediate/Flickr.elm
• /edit/examples/Intermediate/Pong.elm
• /edit/examples/WebGL/Cube.elm
• /edit/examples/Reactive/ZipCodes.elm
• /edit/examples/Functional/Either.elm
• /edit/examples/Elements/Texture.elm
• /edit/examples/Elements/Markdown.elm

Some of these links can be migrated to /examples/existingEample others don't have any existing equivalent.

Here is a list of defunct external links:

• http://www.share-elm.com
• http://package.elm-lang.org/packages/evancz/local-channel/latest
• http://package.elm-lang.org/packages/elm-lang/core/latest/Json
• http://package.elm-lang.org/packages/elm-lang/core/latest/JavaScript
• http://www.cs.cmu.edu/~rwh/courses/refinements/papers/PottierRemy04/hmx.pdf
• http://www.grzegorzbalcerek.net/preselm/Tutorial.html
• https://github.com/elm-lang/elm-lang.org/blob/master/frontend/public/examples/Intermediate/GameSkeleton.elm
• http://45.55.164.161:8000/packages/elm-lang/core/2.0.0/Signal#Mailbox

Broken link detection for elm-lang.org required a slightly different approach than usual because the server pretty much always return status code 200. I had to extract the title and compare against the title of the 404 page to verify that these links were broken. I do have a linkchecker logfile for my static version of the site with additional information such as parent page of broken links and line numbers in the static versions of these pages. I'm not sure how helpful this would be since there is no direct relation to the elm code line numbers of the current version of the site. Please let me know if you need additional information.

I'm almost done converting everything to a Hykall database.

Bernd

[jvoigtlaender]

Thanks for doing this!

It seems your method does not catch all broken links? For example, the page http://elm-lang.org/blog/interactive-programming contains a link to http://elm-lang.org/edit/examples/Intermediate/Bounce.elm, and that link 404s, but is not listed above.

[berndca]

You are of course correct. /edit/examples/Intermediate/Bounce.elm used in an iframe on /blog/interactive-programming is another missing link. I spend quite some time on /blog/interactive-programming since there were issues affecting the video iframes. In the context of debugging this issue I removed the paragraph above the Bounce.elm iframs and the iframe itself. The report is based on the existing static pages and my current page for /blog/interactive-programming does not have this link. Sorry for the confusion.

[jvoigtlaender]

Hah, so I managed to find the one link that you dropped. 😄 I had help, though, since I was looking through other issues about missing links in this repository, to check whether they could be closed now.

Actually, here is another one, probably missing from your list for the very same reason as the other one: http://elm-lang.org/examples/Intermediate.elm.

And, to also keep the information about the iframe around here, quoting myself from one of the other issues:

But what is really a bit embarrassing is the big "404 iframe" inside http://elm-lang.org/blog/interactive-programming that should apparently show a live-editable-and-hotswappable version of that (not anymore existing?) bouncing ball example.

[jvoigtlaender]

So let's think about how to make progress given all the information above now.

My suggestion would be to try to collect appropriate redirects here first. For example:

• "http://elm-lang.org/edit/examples/Intermediate/Mario.elm should be http://elm-lang.org/examples/mario"
• "http://elm-lang.org/examples/Intermediate.elm should be http://elm-lang.org/examples"
• etc.

Based on that information, we can then search systematically for occurrences of stale links and replace them with current ones, or, where appropriate, instead add the redirects to this list.

[evancz]

I added checkboxes to all the broken links. It seems like many are from the website revamp where a bunch of paths changed, so they should be easy.

Ideally, we could do the fixes one at a time, so a single PR fixes a single link. This will be very very easy to review and nothing will block anything. Furthermore, you can make the changes through github even. So that's how I think we should go.

Also, thanks @berndca for getting this all together! :D

[berndca]

You can find more details about the broken links such as the parent file in this spreadsheet created by the linkchecker utility. For the implementation of the static website I applied three types of modifications.

1. Redirects for broken internal links with existing target.
2. Update of href attribute in broken external links with existing target.
3. Deactivating of links without existing target.

Here is the list of my redirects (from, to):

    Redirect("Documentation.elm", "docs"),
    Redirect("Examples.elm", "examples"),
    Redirect("Install.elm", "install"),
    Redirect("Learn.elm", "docs"),
    Redirect("try", "examples/try"),
    Redirect("learn/What-is-FRP.elm", "guide/reactivity"),
    Redirect("learn/Syntax.elm", "docs/syntax"),
    Redirect("learn/Records.elm", "docs/records"),
    Redirect("learn/Union-Types.elm", "guide/model-the-problem"),
    Redirect("learn/Ports.elm", "guide/interop"),
    Redirect("learn/Tasks.elm", "guide/reactivity"),
    Redirect("learn/Components.elm", "guide/interop"),
    Redirect("learn/Pattern-Matching.elm", "guide/model-the-problem"),
    Redirect("blog/Pong.elm", "blog/making-pong"),
    Redirect("blog/Interactive-Programming.elm", "blog/interactive-programming"),
    Redirect("blog/announce/Repl.elm", "blog/announce/repl"),
    Redirect("blog/announce/PackageManager.elm", "blog/announce/package-manager"),
    Redirect("blog/Introducing-Elm-Reactor.elm", "blog/time-travel-made-easy"),
    Redirect("blog/Blazing-Fast-Html.elm", "blog/blazing-fast-html"),
    Redirect("edit/examples/Intermediate/Mario.elm", "examples/mario"),
    Redirect("edit/examples/Intermediate/Flickr.elm", "examples/flickr"),
    Redirect("edit/examples/Intermediate/Pong.elm", "examples/pong"),
    Redirect("edit/examples/WebGL/Cube.elm", "examples/cube"),
    Redirect("edit/examples/JavaScript/ZipCodes.elm", "examples/zip-codes"),
    Redirect("edit/examples/Reactive/ZipCodes.elm", "examples/zip-codes"),
    Redirect("edit/examples/Functional/Either.elm", "examples/either"),
    Redirect("edit/examples/Elements/Position.elm", "examples/mouse-position"),
    Redirect("edit/examples/Elements/Texture.elm", "examples/texture"),
    Redirect("edit/examples/Elements/Markdown.elm", "examples/markdown")

The list of changed external target can be found in this spreadsheet and the list of inactive links is here. All but two instances are links. There is however one iframe (Thwomb) in blog/announce/12.3 and one image (Tango-Palette.png) in blog/announce/0.10 in the inactive links.

Hope this helps.

[evancz]

Thanks @jvoigtlaender for fixing some of the existing links.

To share from another discussion, I think it makes the most sense to fix internal links rather than do redirects. There may be links on the internet to these things, but I think it still makes sense to fix the ones we own.

Also, many of the redirects listed by @berndca already exist here, but I think we should still fix the local links.