How to use Delve debugger in Visual Studio Code

I have installed the Go extension for VS Code, but unable to make it work.

“dlv debug” works alright from the terminal.

dlv debug src/github.com/user/hello

The launch.json :

{
    "version": "0.2.0",
    "configurations": [
        {
            "name": "Launch",
            "type": "go",
            "request": "launch",
            "mode": "debug",
            "program": "${workspaceRoot}",
            "env": {},
            "args": []
        }
    ]
}

Do you know how to set it up?