Control socket (WIP)

anonstream/__init__.py

@@ -59,6 +59,13 @@ def create_app(config_file):
 
     @app.before_serving
     async def startup():
+        # Start control server
+        from anonstream.control.server import start_control_server_at
+        async def start_control_server():
+            return await start_control_server_at(app.config['CONTROL_ADDRESS'])
+        app.add_background_task(start_control_server)
+
+        # Create routes and background tasks
         import anonstream.routes
         import anonstream.tasks
 

anonstream/config.py

@@ -13,6 +13,7 @@ def update_flask_from_toml(toml_config, flask_config):
     flask_config.update({
         'SECRET_KEY_STRING': toml_config['secret_key'],
         'SECRET_KEY': toml_config['secret_key'].encode(),
+        'CONTROL_ADDRESS': toml_config['control']['address'],
         'AUTH_USERNAME': toml_config['auth']['username'],
         'AUTH_PWHASH': auth_pwhash,
         'AUTH_TOKEN': generate_token(),

anonstream/control/server.py

@@ -0,0 +1,125 @@
+import asyncio
+import json
+
+from anonstream.stream import get_stream_title
+
+def start_control_server_at(address):
+    return asyncio.start_unix_server(
+        handle_control_client,
+        address,
+    )
+
+async def handle_control_client(reader, writer):
+    while line := await reader.readline():
+        try:
+            request = line.decode('utf-8')
+        except UnicodeDecodeError as e:
+            response = f'error: {e}'
+        else:
+            method, args, normal, response = await parse(request)
+            if method is None:
+                pass
+            elif normal is not None:
+                writer.write(f'{normal}\n'.encode())
+            elif response is not None:
+                writer.write(f'error: '.encode())
+        if response is not None:
+            writer.write(response.encode())
+            await writer.drain()
+        else:
+            writer.close()
+            break
+
+async def parse(request):
+    try:
+        method, *args = request.split()
+    except ValueError:
+        method, args, normal, response = None, [], None, ''
+    else:
+        match method:
+            case 'help':
+                normal_args, response = await parse_help(args)
+            case 'exit':
+                normal_args, response = await parse_exit(args)
+            case 'title':
+                normal_args, response = await parse_title(args)
+            case _:
+                normal_args = None
+                response = f"method {method!r} is unknown, try 'help'\n"
+        if normal_args is None:
+            normal = None
+            if response is None:
+                response = f"command {args[0]!r} is unknown, try {f'{method} help'!r}\n"
+        elif len(normal_args) == 0:
+            normal = method
+        else:
+            normal = f'{method} {" ".join(normal_args)}' or method
+    return method, args, normal, response
+
+async def parse_help(args):
+    match args:
+        case []:
+            normal_args = []
+            response = (
+                'Usage: METHOD {COMMAND | help}\n'
+                'Examples:\n'
+                ' help.......................show this help message\n'
+                ' exit.......................close the connection\n'
+                ' title [show [CODEC]].......show the stream title\n'
+                ' title set TITLE............set the stream title\n'
+                ' user [show]................show a list of users\n'
+                ' user set USER ATTR VALUE...set an attribute of a user\n'
+            )
+        case ['help']:
+            normal_args = ['help']
+            response = (
+                'Usage: help\n'
+                'show usage syntax and examples\n'
+            )
+        case _:
+            normal_args = None
+            response = None
+    return normal_args, response
+
+async def parse_exit(args):
+    match args:
+        case []:
+            normal_args = []
+            response = None
+        case ['help']:
+            normal_args = ['help']
+            response = (
+                'Usage: {exit | quit}\n'
+                'close the connection\n'
+            )
+        case _:
+            normal_args = None
+            response = None
+    return normal_args, response
+
+async def parse_title(args):
+    match args:
+        case [] | ['show'] | ['show', 'json']:
+            normal_args = ['show', 'json']
+            response = json.dumps(await get_stream_title()) + '\n'
+        case ['show', 'utf-8']:
+            normal_args = ['show']
+            response = await get_stream_title() + '\n'
+        case ['show', arg, *_]:
+            normal_args = None
+            response = f"option {arg!r} is unknown, try 'title help'\n"
+        case ['help']:
+            normal_args = ['help']
+            response = (
+                'Usage: title {show [CODEC] | set TITLE}\n'
+                'Commands:\n'
+                ' title show [CODEC].....show the stream title\n'
+                ' title set TITLE........set the stream title to TITLE collapsing whitespace\n'
+                'Arguments:\n'
+                ' CODEC..................=[utf-8 | json]\n'
+                ' TITLE..................a UTF-8-encoded string\n'
+            )
+        case _:
+            normal_args = None
+            response = None
+    return normal_args, response

config.toml

@@ -1,5 +1,8 @@
 secret_key = "place secret key here"
 
+[control]
+address = "control.sock"
+
 [auth]
 username = "broadcaster"