The rust getting started sample should use the vscode extension

[sunix]

Is your enhancement related to a problem? Please describe.

At the moment, testing the rust devfile from getting started section in the dashboard: we can build and run ... but no code completion ... nor debug
Could https://github.com/rust-lang/rls-vscode/releases be tested and integrated?

Also it would be nice to see if we could enable the debug mode.

[sunix]

Progress:

• Created a cheplugin https://gist.github.com/sunix/eb86fdf6802afbfb4de059ed19f08d37 for testing
• Problem with the vscode extension: can’t load module rust-analysis, though it works from the terminal.
• Investigation:
  • Creating a devfile to run the rust ext from source and execute it in a sidecar. https://github.com/eclipse/che-theia/blob/sunix-rust-extension-devfile/devfiles/vscode-rust-devfile.yaml

    2020-11-25 13:13:55.129 task INFO Created new task, id: 0, process id: 0, OS PID: 4996, context: file:///projects 
    2020-11-25 13:13:55.352 terminal ERROR Couldn't attach - can't find terminal with id: 0  
    2020-11-25 13:13:55.655 root ERROR Couldn't resize terminal -1, because it doesn't exist. 
    2020-11-25 13:13:55.656 terminal ERROR Error attaching to terminal id 0, the terminal is most likely gone. Starting up a new terminal instead.
    

  • https://github.com/rust-lang/vscode-rust/blob/master/src/tasks.ts#L137 my guess is that the task is invoked in the theia-ide container, not the rust one.

So currently the options could be:

• test if we could install the dependencies (PS it won’t solve the problem)
• do not use tasks to exec: use exec + output channel in rust-ext and propose a PR?
• somehow detect tasks created and started from a plugin and run these in the right container. Or be able to override tasks and tell them to run in container

To mention during daily meeting:

• Accidentally found another rust vscode extension: https://github.com/editor-rs/vscode-rust (tested https://github.com/rust-lang/vscode-rust )
• Dog fooding: 2 theia in the same container … one gets killed from time to time ….

[sunix]

Progress:

• Build a che-theia editor with rust: https://quay.io/repository/sunix/che-theia-rust
• runing it with the che-editor https://gist.github.com/sunix/a1295a1150f129ad40d2a11c59a3c063

Running in rust vscode ext in the che-theia-rust editor container is also failing: it seems to be something wrong with attaching terminal and not a dependency issue.

2020-11-30 13:46:34.763 root ERROR Couldn't resize terminal -1, because it doesn't exist. 
2020-11-30 13:46:34.763 terminal ERROR Error attaching to terminal id 0, the terminal is most likely gone. Starting up a new terminal instead. 
2020-11-30 13:46:35.782 root ERROR [hosted-plugin: 45748] Promise rejection not handled in one second: Error , reason: Error 
2020-11-30 13:46:35.783 root ERROR [hosted-plugin: 45748] With stack trace: Error
    at /tmp/vscode-unpacked/rust-0.7.8.vsix/extension/out/src/rustup.js:177:27
    at Generator.next (<anonymous>)
    at fulfilled (/tmp/vscode-unpacked/rust-0.7.8.vsix/extension/out/src/rustup.js:5:58)
    at processTicksAndRejections (internal/process/task_queues.js:97:5)

PS: maynot be the root cause

To mention during the daily meeting:

• do we have any devfile samples how to setup debug for vscode ext ?

[sunix]

Progress:

• I managed to have the extension working by preinstalling the dependencies that the extension were not able to install in the theia-ide container.

  rustup component add rust-src --toolchain 1.48.0-x86_64-unknown-linux-musl; \
  rustup component add rust-analysis --toolchain 1.48.0-x86_64-unknown-linux-musl; \
  rustup component add rls --toolchain 1.48.0-x86_64-unknown-linux-musl;
  

and the editor:

  - type: cheEditor
    reference: 'https://gist.githubusercontent.com/sunix/a1295a1150f129ad40d2a11c59a3c063/raw/6089f949e7bfb7eadffe1f9096cddd7de3fd8d97/che-theia-rust-editor.yaml'
    alias: che-theia
    env:
      - value: '0'
        name: NODE_TLS_REJECT_UNAUTHORIZED

next step: trying if providing these dependencies work in a sidecar