Collaborative session implementation, 1

synctoy/main.py

@@ -0,0 +1,55 @@
+import asyncio
+import json
+from pydantic import BaseModel, TypeAdapter
+from starlette.applications import Starlette
+from starlette.middleware import Middleware
+from starlette.middleware.cors import CORSMiddleware
+from starlette.middleware.trustedhost import TrustedHostMiddleware
+from starlette.requests import Request
+from starlette.responses import JSONResponse, Response
+from starlette.routing import Route
+
+from synctoy.data_model import ObjectId, NonNullRecord, Record
+from synctoy.snapshot import SAll
+from synctoy.store import Store, Update
+
+
+store = Store()
+
+_TIMEOUT = 5.0
+
+async def snapshot(request: Request):
+    snapshot = store.snapshot(SAll())
+    populated = snapshot.populated_records()
+    return JSONResponse(TypeAdapter(dict[ObjectId, NonNullRecord]).dump_python(populated, mode="json"))
+
+class UpdateResult(BaseModel):
+    index: int
+
+async def update(request: Request):
+    value = Update.model_validate_json(await request.body())
+    version = store.update([value])
+    return JSONResponse(UpdateResult(index=version).model_dump(mode="json"))
+
+async def events(request: Request):
+    start = request.query_params.get("start")
+    if start is None:
+        start = 0
+    else:
+        start = int(start)
+
+    result = store.observe(start_from=start)
+    if len(result) == 0:
+        await store.wait(_TIMEOUT)
+        result = store.observe(start_from=start)
+
+    await asyncio.sleep(1.0)  # simulated delay! wow
+    return JSONResponse(TypeAdapter(list[Record]).dump_python(result))
+
+app = Starlette(debug=True, routes=[
+    Route("/snapshot", snapshot, methods=["GET"]),
+    Route("/update", update, methods=["POST"]),
+    Route("/events", events, methods=["GET"])
+],
+)
+app = CORSMiddleware(app=app, allow_origins=["*"])