Progress on T179875 has been made \o/

Should we also point them to the RESTbase service in these warning messages?

Remember third party wikis exist and might have TextExtracts installed.

Yeh the idea is that this would be configurable and only updated for Wikimedia services. I've updated the description to make this clearer.

As part of this task, this work includes updating https://www.mediawiki.org/wiki/Reading/Component_responsibility to note "Non-security patches not reviewed."

@Jdlrobson wrote:

You can add warnings like so when certain combos are used:

$main->addWarning( new RawMessage( 'existing warning' ), 'existing-warning' );

If you do that, I will be very unhappy with you. There's never a case where you should use a RawMessage with ->addWarning(), and you shouldn't call it on the ApiMain directly as implied by your specifying $main rather than $this.

The correct way is similar. First, see if one of the existing message keys beginning with "apiwarn-" can be used. If not, copy the warning text to the extension's i18n JSON files with an appropriate key.

Then the basic code to use is

// Simple case
$this->addWarning( 'i18n-message-key' );

// Pass an array to specify parameters for the message.
// Be sure to use `wfEscapeWikiText()` or `Message::plaintextParam()` on parameters that come from user input!
$this->addWarning( [ 'i18n-message-key', 'parameter1', 'etc' ] );

// By default, the machine-readable code for the warning (when `errorformat` is not `bc`) is the i18n message key
// with "apiwarn-" or "apierror-" removed from the beginning, if applicable. You can override that with the second
// parameter to ->addWarning()
$this->addWarning( 'i18n-message-key', 'code' );
$this->addWarning( [ 'i18n-message-key', 'parameter1', 'etc' ], 'code' );

Thank you for updating the description. I just copied and pasted and instance directly from core to help a conversation. I was just explaining the API has an addWarning method baked in, I was not suggesting the usage of RawMessage :) Thanks for providing some better examples.

Good, I'm glad it was just a bad copy-paste rather than a real recommendation. (: For examples of usage it's probably better to look in core API modules rather than in their unit tests.

Also, I see I was wrong. There's one case where RawMessage might be used: unit tests of warning handling. ;)

Change 420753 had a related patch set uploaded (by Jdlrobson; owner: Jdlrobson):
[mediawiki/extensions/TextExtracts@master] Adjust expectations for API consumers when using the TextExtracts API

https://gerrit.wikimedia.org/r/420753

Change 420753 merged by jenkins-bot:
[mediawiki/extensions/TextExtracts@master] Adjust expectations for API consumers when using the TextExtracts API

https://gerrit.wikimedia.org/r/420753

This is technical task, moving directly to sign-off column. @Jhernandez @Jdrewniak @Niedzielski - ready for sign off -> can you double check it and resolve the task?