New build errors: 'The `set-env` command is disabled'

[jwosty]

Hello! My builds have started failing (even when I rerun old successful builds) with the following error traced back to this setup-xamarin action:

Run maxim-lobanov/setup-xamarin@v1.1
  with:
    mono-version: 6.8
    xamarin-mac-version: 6.16
    xcode-version: latest
  env:
    DOTNET_ROOT: /Users/runner/.dotnet
Switching Mono to version '6.8'...
Error: Unable to process command '::set-env name=DYLD_LIBRARY_FALLBACK_PATH::/Library/Frameworks/Mono.framework/Versions/6.8.0/lib:/lib:/usr/lib:' successfully.
Error: The `set-env` command is disabled. Please upgrade to using Environment Files or opt into unsecure command execution by setting the `ACTIONS_ALLOW_UNSECURE_COMMANDS` environment variable to `true`. For more information see: https://github.blog/changelog/2020-10-01-github-actions-deprecating-set-env-and-add-path-commands/
Error: Unable to process command '::set-env name=PKG_CONFIG_PATH::/Library/Frameworks/Mono.framework/Versions/6.8.0/lib/pkgconfig:/Library/Frameworks/Mono.framework/Versions/6.8.0/share/pkgconfig:' successfully.
Error: The `set-env` command is disabled. Please upgrade to using Environment Files or opt into unsecure command execution by setting the `ACTIONS_ALLOW_UNSECURE_COMMANDS` environment variable to `true`. For more information see: https://github.blog/changelog/2020-10-01-github-actions-deprecating-set-env-and-add-path-commands/
Error: Unable to process command '::add-path::/Library/Frameworks/Mono.framework/Versions/6.8.0/bin' successfully.
Error: The `add-path` command is disabled. Please upgrade to using Environment Files or opt into unsecure command execution by setting the `ACTIONS_ALLOW_UNSECURE_COMMANDS` environment variable to `true`. For more information see: https://github.blog/changelog/2020-10-01-github-actions-deprecating-set-env-and-add-path-commands/
Mono is set to '6.8.0.123'
Switching Xamarin.Mac to version '6.16'...
Xamarin.Mac is set to '6.16.0.13'
Switching Xcode to version 'latest'...
Error: Unable to process command '::set-env name=MD_APPLE_SDK_ROOT::/Applications/Xcode_12.3.app' successfully.
Error: The `set-env` command is disabled. Please upgrade to using Environment Files or opt into unsecure command execution by setting the `ACTIONS_ALLOW_UNSECURE_COMMANDS` environment variable to `true`. For more information see: https://github.blog/changelog/2020-10-01-github-actions-deprecating-set-env-and-add-path-commands/
Xcode is set to '12.3'

They used to work; I have changed nothing but now they are failing. Is this something that should be fixed on my end in my repo, or is it a problem with this github action? I am about to just try updating all the actions to see if that fixes it; will report back soon.

[jwosty]

Ah, I noticed my workflow was using setup-xamarin@v1.1. Upgrading to setup-xamarin@v1 seems to have fixed it.

[maxim-lobanov]

@jwosty , Yep, it is correct. GitHub is deprecating support of old commands.
Switching to v1.2 or v1 tag (that points to latest 1.x) is fixing an issue.

[jwosty]

Deprecation comes fast these days! ;)

Thanks for the explanation.