docs: better place for application_name

docs/postgrest.dict

@@ -157,7 +157,6 @@ stateful
 stdout
 supervisees
 SvelteKit
-syslog
 systemd
 todo
 todos

docs/references/connection_pool.rst

@@ -7,11 +7,6 @@ A connection pool is a cache of reusable database connections. It allows serving
 
 Minimizing connections is paramount to performance. Each PostgreSQL connection creates a process, having too many can exhaust available resources.
 
-Connection String
------------------
-
-For connecting to the database, the pool requires a connection string. You can configure it using :ref:`db-uri`.
-
 .. _pool_growth_limit:
 .. _dyn_conn_pool:
 
@@ -22,6 +17,26 @@ To conserve system resources, PostgREST uses a dynamic connection pool. This ena
 
 - If all the connections are being used, a new connection is added. The pool can grow until it reaches the :ref:`db-pool` size. Note that it’s pointless to set this higher than the ``max_connections`` setting in your database.
 - If a connection is unused for a period of time (:ref:`db-pool-max-idletime`), it will be released.
+- For connecting to the database, the :ref:`authenticator <roles>` role is used. You can configure this using :ref:`db-uri`.
+
+Connection Application Name
+~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+PostgREST sets the connection `application_name <https://www.postgresql.org/docs/current/libpq-connect.html#LIBPQ-CONNECT-FALLBACK-APPLICATION-NAME>`_ for all of its used connections.
+This is useful for PostgreSQL statistics and logs.
+
+For example, you can query `pg_stat_activity <https://www.postgresql.org/docs/current/monitoring-stats.html#MONITORING-PG-STAT-ACTIVITY-VIEW>`_ to get the PostgREST version:
+
+.. code-block:: postgres
+
+  select distinct usename, application_name
+  from pg_stat_activity
+  where usename = 'authenticator';
+
+     usename     |     application_name
+  ---------------+--------------------------
+   authenticator | PostgREST 12.1
+
 
 Connection lifetime
 -------------------

docs/references/observability.rst

@@ -20,33 +20,20 @@ PostgREST logs basic request information to ``stdout``, including the authentica
    127.0.0.1 - user [26/Jul/2021:01:56:38 -0500] "GET /clients HTTP/1.1" 200 - "" "curl/7.64.0"
    127.0.0.1 - anonymous [26/Jul/2021:01:56:48 -0500] "GET /unexistent HTTP/1.1" 404 - "" "curl/7.64.0"
 
-For diagnostic information about the server itself, PostgREST logs to ``stderr``.
+For diagnostic information about the server itself, PostgREST logs to ``stderr``. It includes the server version and also the version of the connected PostgreSQL.
 
 .. code::
 
-   12/Jun/2021:17:47:39 -0500: Starting PostgREST 11.1.0...
-   12/Jun/2021:17:47:39 -0500: Attempting to connect to the database...
-   12/Jun/2021:17:47:39 -0500: Listening on port 3000
-   12/Jun/2021:17:47:39 -0500: Connection successful
-   12/Jun/2021:17:47:39 -0500: Config re-loaded
-   12/Jun/2021:17:47:40 -0500: Schema cache loaded
-
-.. note::
-
-   When running it in an SSH session you must detach it from stdout or it will be terminated when the session closes. The easiest technique is redirecting the output to a log file or to the syslog:
-
-   .. code-block:: bash
-
-     ssh [email protected] \
-       'postgrest foo.conf </dev/null >/var/log/postgrest.log 2>&1 &'
-
-     # another option is to pipe the output into "logger -t postgrest"
-
-Currently PostgREST doesn't log the SQL commands executed against the underlying database.
+   06/May/2024:08:16:11 -0500: Starting PostgREST 12.1...
+   06/May/2024:08:16:11 -0500: Attempting to connect to the database...
+   06/May/2024:08:16:11 -0500: Successfully connected to PostgreSQL 14.10 (Ubuntu 14.10-0ubuntu0.22.04.1) on x86_64-pc-linux-gnu, compiled by gcc (Ubuntu 11.4.0-1ubuntu1~22.04) 11.4.0, 64-bit
+   06/May/2024:08:16:11 -0500: Listening on port 3000
 
 Database Logs
 -------------
 
+Currently PostgREST doesn't log the SQL commands executed against the underlying database.
+
 To find the SQL operations, you can watch the database logs. By default PostgreSQL does not keep these logs, so you'll need to make the configuration changes below.
 
 Find :code:`postgresql.conf` inside your PostgreSQL data directory (to find that, issue the command :code:`show data_directory;`). Either find the settings scattered throughout the file and change them to the following values, or append this block of code to the end of the configuration file.
@@ -172,33 +159,17 @@ Max pool connections.
 Traces
 ======
 
-Server Version
---------------
-
-When debugging a problem it's important to verify the running PostgREST version. There are three ways to do this:
+Server Version Header
+---------------------
 
-- Look for the :code:`Server` HTTP response header that is returned on every request.
+When debugging a problem it's important to verify the running PostgREST version. For this you can look at the :code:`Server` HTTP response header that is returned on every request.
 
 .. code::
 
   HEAD /users HTTP/1.1
 
   Server: postgrest/11.0.1
 
-- Query ``application_name`` on `pg_stat_activity <https://www.postgresql.org/docs/current/monitoring-stats.html#MONITORING-PG-STAT-ACTIVITY-VIEW>`_.
-
-.. code-block:: postgres
-
-  select distinct application_name
-  from pg_stat_activity
-  where application_name ilike '%postgrest%';
-
-        application_name
-  ------------------------------
-  PostgREST 11.1.0
-
-- The ``stderr`` logs also contain the version, as noted on :ref:`pgrst_logging`.
-
 .. _trace_header:
 
 Trace Header
@@ -348,6 +319,7 @@ For example, to only allow requests from an IP address to get the execution plan
 
     const redirects = {
       '#health_check': 'health_check.html',
+      '#server-version': '#server-version-header',
     };
 
     let willRedirectTo = redirects[hash];