Interface

After launching, Judy should immediately accept one connection on localhost:8000 and one on localhost:18001, before executing any code. The first connection carries requests (from adapter to debugger). The second connection carries events (from debugger to adapter). The following protocol describes the communication on these connections.

Packet

+-----------------------------------------------+----------------------------+
| length (8-digit decimal number padded with 0) | JSON data (`length` bytes) |
+-----------------------------------------------+----------------------------+

The JSON data follows JSON-RPC 2.0.

Example communication on the request connection:

• adapter: 00000112{"jsonrpc": "2.0", "id": 1, "method": "setBreakPoints", "params": {"path": "C:\\foo\\bar.jl", "lines": [1, 2, 3]}}
• debugger: 00000141{"jsonrpc": "2.0", "id": 1, "result": [{"verified": false}, {"verified": true, "line": 2, "id": 1}, {"verified": true, "line": 10, "id": 2}]}

Request methods

• initialize

  params: { }

  result: { }

• launch

  params: {"stopOnEntry": stopOnEntry}

  result: '{ }'

• setBreakPoints

  params: {"path": "C:\\foo\\bar.jl", "lines": [1, 2, 3]}

  result: [{"verified": false}, {"verified": true, "line": 2, "id": 1}, {"verified": true, "line": 10, "id": 2}]

• configurationDone

  params: { }

  result: { }

• continue

  params: { }

  result: { }

• next

  params: { }

  result: { }

• threads

  we don't support multi-threading debug, so this request will be responded by the adapter and will not send to the debugger.

• stackTrace

  params: { }

  result: { { "frameId": 1, "name": "my_func", "path": "C:\\foo\\child.jl", "line": 1 }, { "frameId": 2, "name": "my_func2", "path": "C:\\foo\\child.jl", "line": 5 }, { "frameId": 3, "name": "main", "path": "C:\\foo\\parent.jl", "line": 1 } }

• scopes

  params: { "frameId": 1 }

  result: { { "name": "main", "variablesReference": 37, "expensive": false } }

  note: "variablesReference" is the reference of the variable container.

• variables

  params: { "variablesReference": 37 }

  result: { { "name": "my_float", "value": "23.09", "type": "float", "variablesReference": 0 }, { "name": "my_var", "value": "my_class{ _int: 1, _float: 5.99, _string: "too long to show i..." }", "type": "float", "variablesReference": 55 } }

  note: if variablesReference is > 0, the variable is structured and its children can be retrieved by passing variablesReference to the VariablesRequest.

Event methods

All events are notifications, which means they don't need responses.

• initialized

  params: { }

• stopped

  params: { "reason": "step", "description":"", "text": "" }

  note: (1)reason values: 'step', 'breakpoint', 'exception', 'pause', 'entry', 'goto', etc. (2) description: full reason for the event, show in UI (3) text is additional information like exception name, show in UI

• exited

  params: { "exitCode": 0 }

some reminders

1. On Windows: add your Julia binary to VSCode Settings:

"julia.executablePath": "C:\\Your\\Path\\to\\Julia-1.0.2\\bin\\julia.exe"

2. Debugging your extension: use Server + Extension debug mode.