chore: fix pgbouncer manifest

Bitnami's Docker image for PgBouncer has some unclear default settings,
which caused my incorrect manifest to work. This has been fixed now.

Author: edwardzjl

manifests/components/pgbouncer/deployment.yaml

@@ -19,9 +19,9 @@ spec:
           image: bitnami/pgbouncer:latest
           envFrom:
             - configMapRef:
-                name: pgbouncer
+                name: pgbouncer-bitnami
             - secretRef:
-                name: pgbouncer
+                name: pgbouncer-bitnami
           ports:
             - containerPort: 5432
               name: session-prt
@@ -31,13 +31,20 @@ spec:
               cpu: 50m
               memory: 50Mi
           volumeMounts:
-            - name: auth-file
-              mountPath: /etc/pgbouncer/auth_file
+            - name: config-vol
+              mountPath: /bitnami/pgbouncer/conf/
               readOnly: true
       volumes:
-        - name: auth-file
-          secret:
-            secretName: auth-file
+        - name: config-vol  # cannot name it to 'config' or kubernetes will not be able to find it.
+          projected:
+            sources:
+              - configMap:
+                  name: pgbouncer
+              - secret:
+                  name: pgbouncer
+                  items:
+                    - key: auth_file
+                      path: userlist.txt
       # assign pods to nodes with the postgres primary
       affinity:
         podAffinity:

manifests/components/pgbouncer/kustomization.yaml

@@ -7,16 +7,21 @@ resources:
 
 configMapGenerator:
   - name: pgbouncer
+    files:
+      - pgbouncer.ini
+  # The bitnami pgbouncer image requires some environment variables to work, although they are overridden by the config file
+  - name: pgbouncer-bitnami
     envs:
       - params.env
 
 secretGenerator:
   - name: pgbouncer
-    envs:
-      - secret-params.env
-  - name: auth-file
     files:
       - auth_file
+  # The bitnami pgbouncer image requires some environment variables to work, although they are overridden by the config file
+  - name: pgbouncer-bitnami
+    envs:
+      - secret-params.env
 
 images:
   - name: bitnami/pgbouncer

manifests/components/pgbouncer/params.env

@@ -1,10 +1,2 @@
 POSTGRESQL_HOST=postgres.postgres-shared.svc.cluster.local
 PGBOUNCER_PORT=5432
-PGBOUNCER_DEFAULT_POOL_SIZE=100
-PGBOUNCER_MAX_CLIENT_CONN=100
-PGBOUNCER_POOL_MODE=session
-PGBOUNCER_IGNORE_STARTUP_PARAMETERS=extra_float_digits,search_path
-# PgBouncer exposed database. This is the database that clients can connect to.
-PGBOUNCER_DATABASE=chatbot
-PGBOUNCER_AUTH_USER=chatbot
-PGBOUNCER_AUTH_TYPE=scram-sha-256

manifests/components/pgbouncer/pgbouncer.ini

@@ -0,0 +1,26 @@
+; This file is modified on a base generated by <https://hub.docker.com/r/bitnami/pgbouncer>
+; The source code of the base image can be found at <https://github.com/bitnami/containers/tree/main/bitnami/pgbouncer>
+
+[databases]
+chatbot = host=postgres.postgres-shared.svc.cluster.local port=5432 dbname=chatbot auth_user=chatbot pool_size=200
+chatbot-standby = host=postgres-replica.postgres-shared.svc.cluster.local port=5432 dbname=chatbot auth_user=chatbot pool_size=200
+* = host=postgres.postgres-shared.svc.cluster.local
+
+[pgbouncer]
+listen_port=5432
+listen_addr=0.0.0.0
+unix_socket_dir=/tmp/
+unix_socket_mode=0777
+auth_file=/opt/bitnami/pgbouncer/conf/userlist.txt
+auth_type=scram-sha-256
+pidfile=/opt/bitnami/pgbouncer/tmp/pgbouncer.pid
+admin_users=chatbot
+client_tls_sslmode=disable
+server_tls_sslmode=disable
+pool_mode=session
+max_client_conn=400
+default_pool_size=100
+ignore_startup_parameters=extra_float_digits
+stats_period=60
+server_round_robin=0
+server_fast_close=0