Added automatic markdown link checking and fixed broken links

[Jimmys20]

Fixes #1969

This PR enables automatic markdown link checking using markdown-link-check utility. I fixed most of the broken links and I created an ignore list for the links I wasn't sure how to fix.

Microsoft Reviewers: Open in CodeFlow

[krwq]

LGTM, +1 if you make our build break whenever there is any broken link. Possibly markdownlint has option for that: https://github.com/dotnet/iot/blob/main/.vsts-ci.yml#L107

[krwq]

FYI: https://github.com/tcort/markdown-link-check

[krwq]

You can use something similar to this to run it on all files:

ls -r *.md | %{markdown-link-check $_.FullName; if (-Not $?) { throw "One of the links is wrong" } }

There are plenty of other dead links in the repo.

Probably some configuration will be needed as well to ignore some of the bad links (some require authentication)

[Jimmys20]

This is the list of the problematic links according to markdown-link-check that I wasn't sure how to fix:

• src\devices\Amg88xx\README.md

  • https://eu.industrial.panasonic.com/sites/default/pidseu/files/downloads/files/

• src\devices\Ak8963\README.md

  • https://www.akm.com/akm/en/file/datasheet/AK8963C.pdf

• src\devices\README.md

  • https://dotnet.myget.org/feed/dotnet-core/package/nuget/Iot.Device.Bindings

• samples\bmp280-sensor-azure-iot-hub\Readme.md

  • ../.vscode/launch.json
  • ../.vscode/tasks.json

• Documentation\creating-new-release.md

  • https://dev.azure.com/dnceng/internal/_build?definitionId=239

• Documentation\README.md

  • https://www.pine64.org/?page_id=46823

• src\devices\Media\VideoDevice\samples\MjpegStream\README.md

  • http://url/image/settimezone?timezone=1
  • http://url/image
  • http://url/image/stream

• src\devices\Pca95x4\README.md

  • http://ecee.colorado.edu/~mcclurel/Philips_I2C_IO_Expanders_AN469_2.pdf

• src\devices\Mpu6886\README.md

  • https://m5stack.oss-cn-shenzhen.aliyuncs.com/resource/docs/datasheet/core/MPU-6886-000193%2Bv1.1_GHIC_en.pdf

broken-links.txt

Certain paths can be ignored by adding the appropriate pattern to .mlc-config.json e.g.:

{
  "ignorePatterns": [
    {
      "pattern": "^http://example.net"
    }
  ]
}

[krwq]

@Jimmys20 I'll suggest create that config file and add each link with missing datasheet or similar (outside of our repo) individually and fix it separately outside of this PR. Once you're done let's open issue and point to that ignore file that those datasheets are missing and let's figure out path forward (possibly we should be copying those datasheets into our repo, not sure but we should figure out generic solution). In this PR let's focus on enabling the automatic checks and make sure links within the repo are correct.

If you can find alternative link to datasheet that's fine too 😄 But I think we should open issue anyway because eventually another external link will go 404 and we'll be in the same spot so we should figure out what to do in those situations

[krwq]

I'll suggest to match naming with: https://github.com/dotnet/iot/blob/main/.markdownlint.json

so something like .markdown-link-checker.json

[krwq]

Should the CI be showing link checker errors? I'm not seeing any (or did you fix all of the issues 👀) Possibly it will show only after merging

[Jimmys20]

The last broken links within repo are in https://github.com/dotnet/iot/blob/main/samples/bmp280-sensor-azure-iot-hub/Readme.md: ../.vscode/launch.json and ../.vscode/tasks.json. Any suggestion for those?

[krwq]

File an issue on the patterns we had to add to suppress errors and assuming there is no more errors LGTM and thank you for the effort!

[krwq]

Thanks again @Jimmys20! I'll file an issue shortly