implement backup/restore

postgresql/config/backup.sh

@@ -3,9 +3,12 @@ set -Eeuo pipefail
 
 export PGHOST=/var/run/postgresql
 
-BACKUP_DIR=/backup/$(date +%Y%m%d)
+BACKUP_DIR=/var/lib/postgresql/backup/$(date +%Y-%m-%d_%H-%M-%S)/
 mkdir -p "$BACKUP_DIR"
 
+echo "Starting complete backup of the whole PostgreSQL server..."
+pg_basebackup --pgdata=$BACKUP_DIR --format=tar --manifest-checksums=SHA256 --verbose
+echo "Starting backup of individual databases..."
 psql -c "SELECT datname FROM pg_database WHERE datname NOT IN ('template0', 'template1', 'postgres');" -t | while read db; do
   if [ -z "$db" ]; then
     continue
@@ -14,6 +17,17 @@ psql -c "SELECT datname FROM pg_database WHERE datname NOT IN ('template0', 'tem
   echo "Backup of database $db..."
   pg_dump -c --if-exists "$db" | gzip -c > "$BACKUP_DIR/dump-$db.sql.gz"
 done
-echo "Complete backup of the whole PostgreSQL server..."
-pg_basebackup -D "$BACKUP_DIR/pg_basebackup"
-echo "Backups stored in $BACKUP_DIR"
+echo "Backup stored in $BACKUP_DIR."
+
+# backup rotation / retention policy
+POSTGRES_BACKUP_RETENTION=${POSTGRES_BACKUP_RETENTION:-7}
+if [[ "$POSTGRES_BACKUP_RETENTION" -gt 0 ]] && ls -1ct /var/lib/postgresql/backup/*/backup_manifest &>/dev/null; then
+  echo "Applying backup retention policy: keeping the last $POSTGRES_BACKUP_RETENTION backups."
+  ls -1ct /var/lib/postgresql/backup/*/backup_manifest | tail -n "+$((POSTGRES_BACKUP_RETENTION + 1))" | while read old_backup; do
+    old_backup=$(dirname "$old_backup")
+    echo "Removing old backup: $old_backup"
+    rm -rf "$old_backup"
+  done
+else
+  echo "No backup retention policy applied."
+fi

postgresql/config/config.env

@@ -5,3 +5,4 @@ POSTGRES_HOST_AUTH_METHOD=scram-sha-256
 POSTGRES_INITDB_ARGS=--auth-host=scram-sha-256
 PGPORT=5432
 PG_MAJOR=17
+POSTGRES_BACKUP_RETENTION=7

postgresql/config/init.sh

@@ -0,0 +1,37 @@
+#!/bin/bash
+
+set -Eeuo pipefail
+
+last_backup=""
+for f in /var/lib/postgresql/backup/*/backup_manifest; do
+  # If there are no backups, the glob pattern above won't match any files
+  if [ ! -f "$f" ]; then
+    continue
+  fi
+  
+  # Check if this is the most recent backup
+  if [ -z "$last_backup" ] || [ "$f" -nt "$last_backup" ]; then
+    last_backup="$f"
+  fi
+done
+
+if [ -n "$last_backup" ]; then
+  last_backup=$(dirname "$last_backup")
+  echo "Restoring from last backup: $last_backup..."
+  mkdir -p "$PGDATA"
+  tar -xvf "$last_backup/base.tar" -C "$PGDATA" 
+  if [ -f "$last_backup/pg_wal.tar" ]; then
+    mkdir -p "$PGDATA/pg_wal"
+    tar -xvf "$last_backup/pg_wal.tar" -C "$PGDATA/pg_wal"
+  fi
+  echo "Verifying backup integrity..."
+  pg_verifybackup -m "$last_backup/backup_manifest" "$PGDATA"
+  echo "Setting ownership and permissions..."
+  chown -R postgres:postgres "$PGDATA"
+  chmod 700 "$PGDATA"
+  echo "Restoration complete."
+  exit 0
+fi
+
+echo "No previous backup found, initializing an empty database!"
+exec /usr/local/bin/docker-ensure-initdb.sh

postgresql/postgresql-backup.container

@@ -25,12 +25,8 @@ User=postgres
 Volume=/var/lib/quadlets/postgresql:/var/lib/postgresql:z
 Volume=/etc/quadlets/postgresql/backup.sh:/usr/local/bin/backup.sh:z,ro
 
-# This container is part of a Pod
-Pod=postgresql.pod
-
 # Share /var/run/postgresql/ between containers in the pod for the Unix socket
 Volume=/var/run/quadlets/postgresql:/var/run/postgresql:z
-Volume=/var/lib/quadlets/postgresql/backup:/backup:z
 
 [Service]
 Restart=no

postgresql/postgresql-init.container

@@ -27,13 +27,11 @@ Environment=PGDATA=/var/lib/postgresql/${PG_MAJOR}/docker
 EnvironmentFile=/etc/quadlets/postgresql/config.env
 
 # Use the official entrypoint script to initialize the database
-Entrypoint=/usr/local/bin/docker-ensure-initdb.sh
+Entrypoint=/usr/local/bin/init.sh
 
 # Volume mounts
 Volume=/var/lib/quadlets/postgresql:/var/lib/postgresql:z
-
-# This container is part of a Pod
-Pod=postgresql.pod
+Volume=/etc/quadlets/postgresql/init.sh:/usr/local/bin/init.sh:z,ro
 
 [Service]
 Restart=no

postgresql/postgresql-server.container

@@ -41,9 +41,6 @@ HealthTimeout=10s
 HealthStartPeriod=60s
 HealthRetries=3
 
-# This container is part of a Pod
-Pod=postgresql.pod
-
 # Share /var/run/postgresql/ between containers in the pod for the Unix socket
 Volume=/var/run/quadlets/postgresql:/var/run/postgresql:z
 

postgresql/postgresql-upgrade.container

@@ -32,9 +32,6 @@ EnvironmentFile=/etc/quadlets/postgresql/config.env
 # Volume mounts
 Volume=/var/lib/quadlets/postgresql:/var/lib/postgresql:z
 
-# This container is part of a Pod
-Pod=postgresql.pod
-
 [Service]
 Restart=no
 TimeoutStartSec=600

postgresql/postgresql.pod

@@ -1,17 +0,0 @@
-[Unit]
-Description=PostgreSQL Database Server - Pod
-Documentation=https://hub.docker.com/_/postgres/
-After=network.target
-Before=postgresql.target
-
-# Only start if PostgreSQL has been configured
-ConditionPathExists=/etc/quadlets/postgresql/config.env
-
-# Start/stop this unit when the target is started/stopped
-PartOf=postgresql.target
-
-[Pod]
-PodName=postgresql
-
-[Install]
-WantedBy=postgresql.target

postgresql/postgresql.target

@@ -1,8 +1,8 @@
 [Unit]
 Description=PostgreSQL Service Target
 Documentation=man:systemd.target(5)
-Requires=postgresql-pod.service postgresql-server.service postgresql-upgrade.service postgresql-init.service postgresql-set-major.service
-After=postgresql-pod.service postgresql-server.service postgresql-upgrade.service postgresql-init.service postgresql-set-major.service
+Requires=postgresql-server.service postgresql-upgrade.service postgresql-init.service postgresql-set-major.service
+After=postgresql-server.service postgresql-upgrade.service postgresql-init.service postgresql-set-major.service
 
 # Allow isolation - can stop/start this target independently
 AllowIsolate=yes