more debug prints

python/lsst/daf/butler/remote_butler/server/handlers/_external_query.py

@@ -66,20 +66,23 @@
 def query_execute(
     request: QueryExecuteRequestModel, factory: Factory = Depends(factory_dependency)
 ) -> StreamingResponse:
+    print("top")
     # Managing the lifetime of the query context object is a little tricky.  We
     # need to enter the context here, so that we can immediately deal with any
     # exceptions raised by query set-up.  We eventually transfer control to an
     # iterator consumed by FastAPI's StreamingResponse handler, which will
     # start iterating after this function returns.  So we use this ExitStack
     # instance to hand over the context manager to the iterator.
     with ExitStack() as exit_stack:
+        print("before context")
         ctx = exit_stack.enter_context(_get_query_context(factory, request.query))
         spec = request.result_spec.to_result_spec(ctx.driver.universe)
 
         # We write the response incrementally, one page at a time, as
         # newline-separated chunks of JSON.  This allows clients to start
         # reading results earlier and prevents the server from exhausting
         # all its memory buffering rows from large queries.
+        print("before stream")
         output_generator = _stream_query_pages(
             # Transfer control of the context manager to
             # _stream_query_pages.
@@ -96,7 +99,9 @@ def query_execute(
 def _retrieve_query_pages(ctx: _QueryContext, spec: ResultSpec) -> Iterator[QueryExecuteResultData]:
     """Execute the database query and and return pages of results."""
     try:
+        print("before execute")
         pages = ctx.driver.execute(spec, ctx.tree)
+        print("page1")
         for page in pages:
             yield convert_query_page(spec, page)
     except ButlerUserError as e:
@@ -133,6 +138,7 @@ async def _stream_query_pages(
     # Ensure that the database connection is cleaned up by taking control of
     # exit_stack.
     async with contextmanager_in_threadpool(exit_stack):
+        print("in context")
         iterator = iterate_in_threadpool(_retrieve_query_pages(ctx, spec))
         done = False
         while not done:
@@ -154,16 +160,19 @@ async def _fetch_next_with_keepalives(
     return a value.  Yields `None` if there is nothing left to read from the
     iterator.
     """
+    print("fetch_next")
     try:
         future = asyncio.ensure_future(anext(iterator, None))
         ready = False
         while not ready:
             (finished_task, pending_task) = await asyncio.wait([future], timeout=15)
             if pending_task:
+                print("timeout")
                 # Hit the timeout, send a keep-alive and keep waiting.
                 yield QueryKeepAliveModel()
             else:
                 # The next value from the iterator is ready to read.
+                print("done")
                 ready = True
     finally:
         # Even if we get cancelled above, we need to wait for this iteration to