[*] improve pg container (#1311)

* Grant execute privilege on `pg_read_file()

* Mount `postgres` container data directory

Author: 0xgouda

docker/bootstrap/create_role_db.sql

@@ -6,5 +6,10 @@ CREATE DATABASE pgwatch OWNER pgwatch;
 
 CREATE DATABASE pgwatch_metrics OWNER pgwatch;
 
+\c pgwatch_metrics
+-- for remote log parsing to work in case of server_log_event_counts metric is used
+GRANT EXECUTE ON FUNCTION pg_read_file(text, bigint, bigint) TO pgwatch;
+
+\c pgwatch
 -- for remote log parsing to work in case of server_log_event_counts metric is used
 GRANT EXECUTE ON FUNCTION pg_read_file(text, bigint, bigint) TO pgwatch;

docker/compose.postgres.yml

@@ -23,6 +23,7 @@ services:
     environment:
       POSTGRES_HOST_AUTH_METHOD: trust
     volumes:
+      - "pgdata:/var/lib/postgresql"
       - "./bootstrap/init_replication.sh:/docker-entrypoint-initdb.d/init_replication.sh"
       - "./bootstrap/create_role_db.sql:/docker-entrypoint-initdb.d/create_role_db.sql"
     healthcheck:
@@ -75,4 +76,7 @@ services:
         exec postgres -D /var/lib/postgresql/standby -c shared_preload_libraries=pg_stat_statements -c pg_stat_statements.track=all -c track_io_timing=on -c track_functions=pl -c log_destination=csvlog -c logging_collector=on
       "
     links:
-      - postgres
+      - postgres
+
+volumes:
+  pgdata: