Cleanup, bugfixes. Added access control on files and API.

cista/api.py

@@ -0,0 +1,86 @@
+import asyncio
+import typing
+
+import msgspec
+from sanic import Blueprint, SanicException
+
+from cista import watching
+from cista.fileio import FileServer
+from cista.protocol import ControlBase, ErrorMsg, FileRange, StatusMsg
+from cista.util.apphelpers import asend, websocket_wrapper
+
+bp = Blueprint("api", url_prefix="/api")
+fileserver = FileServer()
+
+@bp.before_server_start
+async def start_fileserver(app, _):
+    await fileserver.start()
+
+@bp.after_server_stop
+async def stop_fileserver(app, _):
+    await fileserver.stop()
+
+@bp.websocket('upload')
+@websocket_wrapper
+async def upload(req, ws):
+    alink = fileserver.alink
+    while True:
+        req = None
+        text = await ws.recv()
+        if not isinstance(text, str):
+            raise ValueError(f"Expected JSON control, got binary len(data) = {len(text)}")
+        req = msgspec.json.decode(text, type=FileRange)
+        pos = req.start
+        data = None
+        while pos < req.end and (data := await ws.recv()) and isinstance(data, bytes):
+            sentsize = await alink(("upload", req.name, pos, data, req.size))
+            pos += typing.cast(int, sentsize)
+        if pos != req.end:
+            d = f"{len(data)} bytes" if isinstance(data, bytes) else data
+            raise ValueError(f"Expected {req.end - pos} more bytes, got {d}")
+        # Report success
+        res = StatusMsg(status="ack", req=req)
+        await asend(ws, res)
+        #await ws.drain()
+
+@bp.websocket('download')
+@websocket_wrapper
+async def download(req, ws):
+    alink = fileserver.alink
+    while True:
+        req = None
+        text = await ws.recv()
+        if not isinstance(text, str):
+            raise ValueError(f"Expected JSON control, got binary len(data) = {len(text)}")
+        req = msgspec.json.decode(text, type=FileRange)
+        pos = req.start
+        while pos < req.end:
+            end = min(req.end, pos + (1<<20))
+            data = typing.cast(bytes, await alink(("download", req.name, pos, end)))
+            await asend(ws, data)
+            pos += len(data)
+        # Report success
+        res = StatusMsg(status="ack", req=req)
+        await asend(ws, res)
+        #await ws.drain()
+
+@bp.websocket("control")
+@websocket_wrapper
+async def control(req, ws):
+    cmd = msgspec.json.decode(await ws.recv(), type=ControlBase)
+    await asyncio.to_thread(cmd)
+    await asend(ws, StatusMsg(status="ack", req=cmd))
+
+@bp.websocket("watch")
+@websocket_wrapper
+async def watch(req, ws):
+    try:
+        with watching.tree_lock:
+            q = watching.pubsub[ws] = asyncio.Queue()
+            # Init with full tree
+            await ws.send(watching.refresh())
+        # Send updates
+        while True:
+            await ws.send(await q.get())
+    finally:
+        del watching.pubsub[ws]