DAP Client - asyncpg.exceptions.ConnectionDoesNotExistError

[dtod]

Attaching the full trace error as a file, but including the top part here. I recognize that this might be something internal, but https://github.com/MagicStack/asyncpg/issues/309 indicates perhaps not.

2023-09-25 13:03:18,678 - ERROR - (sqlalchemy.dialects.postgresql.asyncpg.Error) <class 'asyncpg.exceptions.ConnectionDoesNotExistError'>: connection was closed in the middle of operation
[SQL: SELECT pg_catalog.pg_namespace.nspname 
FROM pg_catalog.pg_namespace 
WHERE pg_catalog.pg_namespace.nspname = $1::VARCHAR]
[parameters: ('canvas_logs',)]
(Background on this error at: https://sqlalche.me/e/20/dbapi)
Traceback (most recent call last):
  File "/apps/software/standard/core/anaconda/2020.11-py3.8/lib/python3.8/asyncio/selector_events.py", line 848, in _read_ready__data_received
    data = self._sock.recv(self.max_size)
TimeoutError: [Errno 110] Connection timed out

The above exception was the direct cause of the following exception:

Traceback (most recent call last):
  File "/home/dzt2aq/.local/lib/python3.8/site-packages/sqlalchemy/dialects/postgresql/asyncpg.py", line 528, in _prepare_and_execute
    prepared_stmt, attributes = await adapt_connection._prepare(
  File "/home/dzt2aq/.local/lib/python3.8/site-packages/sqlalchemy/dialects/postgresql/asyncpg.py", line 778, in _prepare
    prepared_stmt = await self._connection.prepare(
  File "/home/dzt2aq/.local/lib/python3.8/site-packages/asyncpg/connection.py", line 565, in prepare
    return await self._prepare(
  File "/home/dzt2aq/.local/lib/python3.8/site-packages/asyncpg/connection.py", line 583, in _prepare
    stmt = await self._get_statement(
  File "/home/dzt2aq/.local/lib/python3.8/site-packages/asyncpg/connection.py", line 397, in _get_statement
    statement = await self._protocol.prepare(
  File "asyncpg/protocol/protocol.pyx", line 168, in prepare
asyncpg.exceptions.ConnectionDoesNotExistError: connection was closed in the middle of operation

[LeventeHunyadi]

It seems as if your PostgreSQL server is closing the connection while SQLAlchemy (a Python library that DAP client library uses internally) is doing a schema discovery (by querying information from system tables in pg_catalog). You would need to check the PostgreSQL server log for the root cause. Some of the operations in DAP client library involve long-running sessions and transactions, and your PostgreSQL server might be configured not to tolerate these.

We are assessing the possibility of a major revision of DAP client library, which would, as a side effect, reduce the time DAP client library needs to keep a database server connection open, reducing the likelihood of these errors. Until this overhaul happens, the best course of action is to adjust PostgreSQL server configuration to be more forgiving.

[dtod]

Thank you!