Is it possible to debug go revel framework from Visual Studio Code?

Question

I'm trying to debug a revel app with visual studio but I can't get it to work.

I've seen this question how to debug revel framework(golang) application in visual studio code(vscode) but no answers yet...

I've tried with this config:

{
  "version": "0.2.0",
  "configurations": [
    {
      "name": "Launch",
      "type": "go",
      "request": "launch",
      "mode": "debug",
      "remotePath": "",
      "port": 2345,
      "host": "127.0.0.1",
      "program": "~/code/go/bin/revel",
      "env": {},
      "args": [],
      "showLog": true
    }
  ]
}

But I'm getting this error: Failed to continue: "The program attribute must point to valid directory, .go file or executable."

I think it must be the rebel binary the one to be run here, but I don't know how to pass the app path, should it go in "args"?

Aurlie

Any args you need to pass go in args, yes. There's documentation available. – Nosy

Hi Zapico... maybe you need to point the path of program to go/bin/revel.d/your-app-folder/the-executable – Cardinalate

Hi again... I am thinking about the compilation... revel is a framework that auto-reloads the executable file when you run it again, if you had changed something in the code (not on the deps)... but in this case I don´t know how could it work. Try and tell us. – Cardinalate

Answer 1

Yes it's possible.

1. Suppose that the GOPATH is C:\Work\golang
2. Revel project name is myapp, thus the location of the project (workspace) will be C:\Work\golang\src\myapp.
3. Make some changes to the controllers etc...
4. Run the application with revel run myapp, then press CTRL+C to exit. This step is necessary to generate corresponding go files. The generated file, i.e. the main package will be available under ${workspaceRoot}/app/tmp/main.go

5. Configure launch.json as follows:

   {
       "version": "0.2.0",
       "configurations": [
           {
               "name": "Launch",
               "type": "go",
               "request": "launch",
               "mode": "debug",
               "remotePath": "",
               "port": 2345,
               "host": "127.0.0.1",
               "env": {},
               "showLog": true,
               "program": "${workspaceRoot}/app/tmp/",
               "args": ["-importPath", "myapp", "-srcPath", "c:\\work\\golang\\src",  "-runMode", "dev"]
           }
       ]
   }
   

6. The important parts are program and args parameters, while the other parameters are unmodified.

7. Set breakpoint and start the delve debugger...

EDIT:

1. Setting args parameter to ["-importPath", "myapp", "-srcPath", "${workspaceRoot}/..", "-runMode", "dev"] also work, and I think this should work in other platforms (Mac, Linux) too.
2. The error message is related to delve issue. See https://github.com/Microsoft/vscode-go/issues/986

Antisana

Thanks for your help!!! My dev env is mac so it's not exactly the same but it seems its "almost there". Now I'm getting this error: could not launch process: dial tcp :64821: getsockopt: connection refused Process exiting with code: 1 – Aurlie

It seems its about my delve installation, I'll check it later. And this answer should be in Revel doc!!! ;) – Aurlie

Thanks for your help @putu, I'm facing different problems now ["-importPath", "myapp", "-srcPath", "${workspaceRoot}/..", "-runMode", "dev"] – Aurlie

If I remove "-runMode" and "dev" from args, it runs, but it seems like it's not loading correctly some files (but it's debugging anyway, THANKS a lot), I think I have a problem with environments in revel or something... – Aurlie

Hello, I am able to show variable values in a floating windows, for a simple example like this(twitter.com/i/moments/880234757807898629), but not for a revel application, I can debug the revel app but not inspect the variables. Any suggestion? – Jeffries

@AlvaroDenisAcosta Perhaps the debugger (and) vscode integration still have some issues. Once I've succeeded to display variable as shown in https://imgur.com/a/2dL8g, but later it won't works. – Antisana