Separate multigrid watcher setup endpoint from watcher start endpoint (#566)

Allows better control over when watching starts so that early starting (i.e. before processing parameter specification) can be avoided

Author: d-j-hatton

src/murfey/instrument_server/api.py

@@ -138,7 +138,7 @@ def check_token(session_id: MurfeySessionID):
 
 
 @router.post("/sessions/{session_id}/multigrid_watcher")
-def start_multigrid_watcher(
+def setup_multigrid_watcher(
     session_id: MurfeySessionID, watcher_spec: MultigridWatcherSpec
 ):
     if controllers.get(session_id) is not None:
@@ -182,6 +182,13 @@ def start_multigrid_watcher(
     watchers[session_id].subscribe(
         controllers[session_id]._multigrid_watcher_finalised, final=True
     )
+    return {"success": True}
+
+
+@router.post("/sessions/{session_id}/start_multigrid_watcher")
+def start_multigrid_watcher(session_id: MurfeySessionID):
+    if watchers.get(session_id) is None:
+        return {"success": False}
     watchers[session_id].start()
     return {"success": True}
 

src/murfey/server/api/instrument.py

@@ -94,7 +94,7 @@ async def check_if_session_is_active(instrument_name: str, session_id: int):
 
 
 @router.post("/sessions/{session_id}/multigrid_watcher")
-async def start_multigrid_watcher(
+async def setup_multigrid_watcher(
     session_id: MurfeySessionID, watcher_spec: MultigridWatcherSetup, db=murfey_db
 ):
     data = {}
@@ -139,6 +139,27 @@ async def start_multigrid_watcher(
     return data
 
 
+@router.post("/sessions/{session_id}/start_multigrid_watcher")
+async def start_multigrid_watcher(session_id: MurfeySessionID, db=murfey_db):
+    data = {}
+    instrument_name = (
+        db.exec(select(Session).where(Session.id == session_id)).one().instrument_name
+    )
+    machine_config = get_machine_config(instrument_name=instrument_name)[
+        instrument_name
+    ]
+    if machine_config.instrument_server_url:
+        async with aiohttp.ClientSession() as clientsession:
+            async with clientsession.post(
+                f"{machine_config.instrument_server_url}/sessions/{session_id}/start_multigrid_watcher",
+                headers={
+                    "Authorization": f"Bearer {instrument_server_tokens[session_id]['access_token']}"
+                },
+            ) as resp:
+                data = await resp.json()
+    return data
+
+
 class ProvidedProcessingParameters(BaseModel):
     dose_per_frame: float
     extract_downscale: bool = True