Support for 'xml/executeClientCommand` access to server from extension

[BoykoAlex]

Spring XML Extension needs two things from the XML server:

• Support for xml/executeClientCommand to execute a command on the client. The client command execution would first try to find a command registered by an LS if not found would attempt to execute a client command (registered command in Eclipse or in VSCode)
• Access to XMLLanguageServer instance to register/unregister command and send xml/executeClientCommand request to the client. Need to work out nice API around it as it looks like XMLLanguageServer or XMLLanguageClient was not meant to be accessed by extensions.

Eclipse Client PR: eclipse-wildwebdeveloper/wildwebdeveloper#543

[fbricon]

@BoykoAlex thanks for your PR. However, before your contribution can be accepted by the project, you need to create and electronically sign an Eclipse Contributor Agreement (ECA):

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[BoykoAlex]

@angelozerr The code is ready for the second code review pass :-) There is also #906 factored out from this PR.

[angelozerr]

@angelozerr The code is ready for the second code review pass :-)

Let me review more but I have read quickly your code and it's seems great.

It should be nice if you could:

• add tests for this command service feature. You could see how we test notification service with InvalidPathWarnerTest

• add documentation for your new custom command support. I would add a section about available services after https://github.com/eclipse/lemminx/blob/master/docs/LemMinX-Extensions.md#adding-language-features:

  • notification service (we will do that)
  • command service.
  • validation service.

For each service it should be nice to give a description and a sample.

There is also #906 factored out from this PR.

Yes I have seen that, thanks.

[angelozerr]

@BoykoAlex we would like to do a release of vscode-xml in the following weeks. Have you planned to work on this issue soon?

[BoykoAlex]

@angelozerr VSCode PR: redhat-developer/vscode-xml#339

[BoykoAlex]

@angelozerr Looks like aside from the opened question of switching xml/executeClientCommand' to workspace/executeClientCommand` everything is addressed and ready to be re-evaluated.
(The vscode PR would be affected by the answer to the question above too)

[angelozerr]

@angelozerr Looks like aside from the opened question of switching xml/executeClientCommand' to workspace/executeClientCommand`

Please wait feedback from @fbricon .

everything is addressed and ready to be re-evaluated.

Your PR seems very great (API, quality of your code, comments, etc), but I have not tested yet.

(The vscode PR would be affected by the answer to the question above too)

That's great, thank a lot, I will review it ASAP.

[angelozerr]

@BoykoAlex could add doc for command please after https://github.com/eclipse/lemminx/blob/master/docs/LemMinX-Extensions.md#adding-language-features

[angelozerr]

@BoykoAlex your PR looks great, let me try to implement a custom command to check your PR.

[angelozerr]

@BoykoAlex could you fix please #905 (comment)

[angelozerr]

@BoykoAlex thanks so much for your great PR and your patience! Awesome!

[BoykoAlex]

Thanks for getting this is in @angelozerr and for the thorough review :-)