This change ensures PostgREST starts listening on a server socket only after it loaded the schema cache and is ready to handle requests. It is no longer going to return 503 errors during startup until the schema cache is loaded.
This is useful when multiple instances run on the same machine, for
example behind a proxy. Unix sockets for web and admin servers can then
be put in the same folder for each instance.
Can be helpful when writing tests as well.
The `if response` check a few rows down would not actually work without
initializing the variable first. It'd throw:
```
E UnboundLocalError: cannot access local variable 'response' where
it is not associated with a value
```
retryingSchemaCacheLoad should not clear existing schema cache upon failure - there is no reason to do that. If there is a communication issue with the database server or db is down, clients are going to get 502 anyway. If it was a glitch when loading the schema cache - the clients are going to use old (stale) schema cache for some time until next retry re-loads it successfully.
There was an oversight on d556cea, `timeout_authenticator` doesn't have
any privileges on the tables so it shouldn't be making requests to the
API server or it will end up with 401 responses.
Replaces the `Maybe [Text]` with `[Text]`. The `Maybe` is unnecessary
because we handle `Just []` and `Nothing` the same way.
Signed-off-by: Taimoor Zaeem <taimoorzaeem@gmail.com>
The PGRST000 database connection error message was "Database connection
error. Retrying the connection.", but reconnection attempts are already
logged separately by the reconnection observation, and on fatal errors
(e.g. authentication failure) PostgREST does not retry at all. Drop the
"Retrying the connection." part, leaving "Database connection error.".
The config dump in Config.hs listed db-config, db-pre-config and the
db-pool-* settings out of alphabetical order, while the rest of the dump
was sorted. Now the whole dump is consistently alphabetical and update
the expected IO test configs to match.
Config variables are tested already via reading the config files in
the `configs/` directory.
If more are to be tested, it should be done via adding a file in
`configs/` and compare it with its associated file in `configs/expected/`.
Signed-off-by: Taimoor Zaeem <taimoorzaeem@gmail.com>
Remove internal schema cache load and relationship load sleep settings plus
the delay wrappers they enabled. Drop IO tests that depended on the removed
settings.
Add an IO test that drops a table while schema cache reload is delayed. It verifies the stale cache path returns PostgreSQL 42P01 and the refreshed cache returns PGRST205.
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.
The functions `drain_stdout` and `match_log` should be in `util.py`
so they can be reused in other modules.
Signed-off-by: Taimoor Zaeem <taimoorzaeem@gmail.com>
Disabling the autovacuum daemon should also help reproducibility in
theory, although I don't know of any cases where we hit a problem with
that.
VACUUM changes the order of rows that PostgreSQL returns for some table
without explicit ordering, thus doing the latter to make it consistently
reproducible.
After ANALYZE estimates are 100% exact for the moment, so some requests
which returned 206 Partial Response now return 200 instead. The fact
that PostgREST returns 206 on an unfiltered endpoint can probably be
considered a bug.
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.
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>
Upgraded warp to 3.4.13 which fixed https://github.com/yesodweb/wai/issues/853
Changed interrupt handling so that instead of killing the main thread, listening sockets are closed which triggers warp graceful shutdown.
This adds a new log line that shows each schema cache query time individually, only on
`log-level=debug`. Like so:
```
$ PGRST_LOG_LEVEL=debug postgrest-with-pg-17 -f test/spec/fixtures/load.sql postgrest-run
....
10/Apr/2026:21:48:45 -0500: Schema cache queried in 192.2 milliseconds
10/Apr/2026:21:48:45 -0500: tables: 72.027 ms, keydeps: 20.118 ms, rels: 6.189 ms, funcs: 35.010 ms, comprels: 4.319 ms, dreps: 1.614 ms, mhandlers: 7.419 ms, tzones: 43.025 ms
```
This helps debug specific schema cache queries being slow like on
https://github.com/PostgREST/postgrest/issues/4613#issuecomment-4210191065 and
https://github.com/PostgREST/postgrest/issues/3046#issuecomment-3469059948.
It also closes https://github.com/PostgREST/postgrest/issues/3215,
which main motivation was to find out which query is slow.
Implementation details
---------------------
To time each query inside a transaction in pure SQL, we do:
```sql
-- start timer
select set_config('pgrst.tmp_x', clock_timestamp()::text, false);
-- run the query
select <query>
-- end timer
select set_config('pgrst.tmp_x', (clock_timestamp() - current_setting('pgrst.tmp_x', false)::timestamptz)::text, false);
-- .... repeated for every query
-- at the end we capture all the timings with
select extract('milliseconds' from current_setting('pgrst.tmp_x', false)::interval), extract(..;
```
Considerations
--------------
Only added this on `log-level=debug` because while the queries are fast
and the data is valuable, it triples the amount of queries we run during schema cache refresh,
which could be troublesome on slow networks. It's possible to reduce the
amount of queries by starting and stopping timers in one statement, but
this would still double the amount of queries and makes the code messy,
doesn't seem worth it.
Also it would pollute pg_stat_statements, it's only required to debug certain
extreme cases anyway.
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.
To avoid repeated querying of `pg_timezone_names` every time schema
cache is reset, `Prefer: timezone` can be disabled by setting
`db-timezone-enabled = false`.
Signed-off-by: Taimoor Zaeem <taimoorzaeem@gmail.com>
These files were added to cover the config dumping of
string comparison operators in `JSPath`. Renaming and
adding a comment in these to make it clear.
Signed-off-by: Taimoor Zaeem <taimoorzaeem@gmail.com>
There is unnecessary coupling between observation messages and emited log entries. This causes schema loading logic to emit redundant events: SchemaCacheSummaryObs and SchemaCacheLoadedObs.
Logically - we want to emit a single event containing both summary and timing information. How it is logged is a different matter and should be decoupled.
This commit
* changes observationMessage function returning Text to observationMessages returning [Text] so that it is possible to return multiple (or zero) messages to log based on an observation event
* Removes SchemaCacheSummaryObs constructor from Observation type and adds summary text to SchemaCacheLoadedObs
Set error verbosity using this config. The verbosity can
be set to `verbose` or `minimal` for client error responses.
This only affects client side HTTP responses, server side logs
are not affected by this config.
Signed-off-by: Taimoor Zaeem <taimoorzaeem@gmail.com>
