Right now metrics observation handler does not track database connections but updates a single Gauge based on HasqlPoolObs events. This is problematic because Hasql pool reports various connection events in multiple phases. The connection state machine is not simple and to precisely report the number of connections in various states, it is necessary to track their lifecycles.
This change adds a ConnTrack data structure and logic to track database connections lifecycles. At the moment it supports "connected" and "inUse" connection counts precisely. The "pgrst_db_pool_available" metric is implemented on top of ConnTrack instead of a simple Gauge.
Proves the failure on https://github.com/PostgREST/postgrest/issues/4622.
This doesn't require additional test infra, only nginx. Taking advantage
of the `stream {}` context which is also compatible with unix socket
besides TCP.
The scheduled linkcheck job fails without notification to maintainers.
To catch the failure, a github workflow step has been added which
comments on issue #4106 so that the maintainers get notified.
Signed-off-by: Taimoor Zaeem <taimoorzaeem@gmail.com>
(cherry picked from commit f90d7d7296)
Observation module exports observationMessage and isDbListenerBug functions. The first one is used only in Logger module and the second one - only in Listener.
This change moves observationMessage function to Logger module and isDbListenerBug function to Listener module, making all three modules more cohesive and lessening dependencies.
It also gives the compiler more opportunities for intra-module inlining and optimization.
Renames the "Functions" in the logs to "RPCs". This clarifies that
we log number of callable functions and not the number of SQL objects.
Signed-off-by: Taimoor Zaeem <taimoorzaeem@gmail.com>
PostgREST failed when querying role settings where current
role name contained uppercase letters. This commit resolves
it by quoting the CURRENT_USER.
Signed-off-by: Taimoor Zaeem <taimoorzaeem@gmail.com>
retryingSchemaCacheLoad flushes the pool upon every retry before it starts reloading the schema. This is too early as schema reloading might take some time during which new connections might be acquired. The consequence is that:
* upon successful schema cache reload we might have some connections created with the old schema cache
* we close connections upon each retry and under load we will keep closing and re-opening connections until schema cache load succeeds
This change is to make sure we flush the pool only after successful schema cache querying but before loading (so that connections acquired during loading wait for it and do not interfere with timing the loading process).
This change introduces a match_log function, that implements lenient matching of log output lines. Tests of log output are retrofited to use the function.
DISCLAIMER:
This commit was authored entirely by a human without the assistance of LLMs.
Using debouncer to trigger schema cache loading makes it difficult to understand when exactly it is triggered.
(cherry picked from commit a4c1d945ee)
Diagnosing problems with listener channel notifications not being handled properly by PostgREST connected to read replicas is difficult. Issues might be related to lost connections and listener not being connected to the right host after failover or database server restarts.
This patch adds logging of actual host:port used by libpq connection opened by the listener. It should make it easier to find out if PostgREST is connected to the right host.
