POSTGRES_XLOG_DIR to specify transaction log dir

Adds support for the POSTGRES_XLOG_DIR environment variable, which specifies where the postgres transaction log is stored.

For some use cases, being able to place the transaction log on a different volume is useful.

Existing support for providing flags via $POSTGRES_INITDB_ARGS is inadequate because of the need to create and chown/chmod the directory prior to running initdb.

Author: DanielDent

9.2/alpine/docker-entrypoint.sh

@@ -36,8 +36,15 @@ if [ "$1" = 'postgres' ] && [ "$(id -u)" = '0' ]; then
 	mkdir -p /var/run/postgresql
 	chown -R postgres /var/run/postgresql
 	chmod g+s /var/run/postgresql
-
-	exec su-exec postgres "$BASH_SOURCE" "$@"
+    # Create the transaction log directory before initdb is run (below) so the directory is owned by the correct user
+    if [ "$POSTGRES_XLOG_DIR" ]; then
+        mkdir -p "$POSTGRES_XLOG_DIR"
+        chmod 700 "$POSTGRES_XLOG_DIR"
+        chown -R postgres "$POSTGRES_XLOG_DIR"
+        POSTGRES_INITDB_ARGS="$POSTGRES_INITDB_ARGS --xlogdir $POSTGRES_XLOG_DIR"
+    fi
+
+	exec gosu postgres "$BASH_SOURCE" "$@"
 fi
 
 if [ "$1" = 'postgres' ]; then

9.2/docker-entrypoint.sh

@@ -36,6 +36,13 @@ if [ "$1" = 'postgres' ] && [ "$(id -u)" = '0' ]; then
 	mkdir -p /var/run/postgresql
 	chown -R postgres /var/run/postgresql
 	chmod g+s /var/run/postgresql
+    # Create the transaction log directory before initdb is run (below) so the directory is owned by the correct user
+    if [ "$POSTGRES_XLOG_DIR" ]; then
+        mkdir -p "$POSTGRES_XLOG_DIR"
+        chmod 700 "$POSTGRES_XLOG_DIR"
+        chown -R postgres "$POSTGRES_XLOG_DIR"
+        POSTGRES_INITDB_ARGS="$POSTGRES_INITDB_ARGS --xlogdir $POSTGRES_XLOG_DIR"
+    fi
 
 	exec gosu postgres "$BASH_SOURCE" "$@"
 fi

9.3/alpine/docker-entrypoint.sh

@@ -36,8 +36,15 @@ if [ "$1" = 'postgres' ] && [ "$(id -u)" = '0' ]; then
 	mkdir -p /var/run/postgresql
 	chown -R postgres /var/run/postgresql
 	chmod g+s /var/run/postgresql
-
-	exec su-exec postgres "$BASH_SOURCE" "$@"
+    # Create the transaction log directory before initdb is run (below) so the directory is owned by the correct user
+    if [ "$POSTGRES_XLOG_DIR" ]; then
+        mkdir -p "$POSTGRES_XLOG_DIR"
+        chmod 700 "$POSTGRES_XLOG_DIR"
+        chown -R postgres "$POSTGRES_XLOG_DIR"
+        POSTGRES_INITDB_ARGS="$POSTGRES_INITDB_ARGS --xlogdir $POSTGRES_XLOG_DIR"
+    fi
+
+	exec gosu postgres "$BASH_SOURCE" "$@"
 fi
 
 if [ "$1" = 'postgres' ]; then

9.3/docker-entrypoint.sh

@@ -36,6 +36,13 @@ if [ "$1" = 'postgres' ] && [ "$(id -u)" = '0' ]; then
 	mkdir -p /var/run/postgresql
 	chown -R postgres /var/run/postgresql
 	chmod g+s /var/run/postgresql
+    # Create the transaction log directory before initdb is run (below) so the directory is owned by the correct user
+    if [ "$POSTGRES_XLOG_DIR" ]; then
+        mkdir -p "$POSTGRES_XLOG_DIR"
+        chmod 700 "$POSTGRES_XLOG_DIR"
+        chown -R postgres "$POSTGRES_XLOG_DIR"
+        POSTGRES_INITDB_ARGS="$POSTGRES_INITDB_ARGS --xlogdir $POSTGRES_XLOG_DIR"
+    fi
 
 	exec gosu postgres "$BASH_SOURCE" "$@"
 fi

9.4/alpine/docker-entrypoint.sh

@@ -36,8 +36,15 @@ if [ "$1" = 'postgres' ] && [ "$(id -u)" = '0' ]; then
 	mkdir -p /var/run/postgresql
 	chown -R postgres /var/run/postgresql
 	chmod g+s /var/run/postgresql
-
-	exec su-exec postgres "$BASH_SOURCE" "$@"
+    # Create the transaction log directory before initdb is run (below) so the directory is owned by the correct user
+    if [ "$POSTGRES_XLOG_DIR" ]; then
+        mkdir -p "$POSTGRES_XLOG_DIR"
+        chmod 700 "$POSTGRES_XLOG_DIR"
+        chown -R postgres "$POSTGRES_XLOG_DIR"
+        POSTGRES_INITDB_ARGS="$POSTGRES_INITDB_ARGS --xlogdir $POSTGRES_XLOG_DIR"
+    fi
+
+	exec gosu postgres "$BASH_SOURCE" "$@"
 fi
 
 if [ "$1" = 'postgres' ]; then

9.4/docker-entrypoint.sh

@@ -36,6 +36,13 @@ if [ "$1" = 'postgres' ] && [ "$(id -u)" = '0' ]; then
 	mkdir -p /var/run/postgresql
 	chown -R postgres /var/run/postgresql
 	chmod g+s /var/run/postgresql
+    # Create the transaction log directory before initdb is run (below) so the directory is owned by the correct user
+    if [ "$POSTGRES_XLOG_DIR" ]; then
+        mkdir -p "$POSTGRES_XLOG_DIR"
+        chmod 700 "$POSTGRES_XLOG_DIR"
+        chown -R postgres "$POSTGRES_XLOG_DIR"
+        POSTGRES_INITDB_ARGS="$POSTGRES_INITDB_ARGS --xlogdir $POSTGRES_XLOG_DIR"
+    fi
 
 	exec gosu postgres "$BASH_SOURCE" "$@"
 fi

9.5/alpine/docker-entrypoint.sh

@@ -36,8 +36,15 @@ if [ "$1" = 'postgres' ] && [ "$(id -u)" = '0' ]; then
 	mkdir -p /var/run/postgresql
 	chown -R postgres /var/run/postgresql
 	chmod g+s /var/run/postgresql
-
-	exec su-exec postgres "$BASH_SOURCE" "$@"
+    # Create the transaction log directory before initdb is run (below) so the directory is owned by the correct user
+    if [ "$POSTGRES_XLOG_DIR" ]; then
+        mkdir -p "$POSTGRES_XLOG_DIR"
+        chmod 700 "$POSTGRES_XLOG_DIR"
+        chown -R postgres "$POSTGRES_XLOG_DIR"
+        POSTGRES_INITDB_ARGS="$POSTGRES_INITDB_ARGS --xlogdir $POSTGRES_XLOG_DIR"
+    fi
+
+	exec gosu postgres "$BASH_SOURCE" "$@"
 fi
 
 if [ "$1" = 'postgres' ]; then

9.5/docker-entrypoint.sh

@@ -36,6 +36,13 @@ if [ "$1" = 'postgres' ] && [ "$(id -u)" = '0' ]; then
 	mkdir -p /var/run/postgresql
 	chown -R postgres /var/run/postgresql
 	chmod g+s /var/run/postgresql
+    # Create the transaction log directory before initdb is run (below) so the directory is owned by the correct user
+    if [ "$POSTGRES_XLOG_DIR" ]; then
+        mkdir -p "$POSTGRES_XLOG_DIR"
+        chmod 700 "$POSTGRES_XLOG_DIR"
+        chown -R postgres "$POSTGRES_XLOG_DIR"
+        POSTGRES_INITDB_ARGS="$POSTGRES_INITDB_ARGS --xlogdir $POSTGRES_XLOG_DIR"
+    fi
 
 	exec gosu postgres "$BASH_SOURCE" "$@"
 fi

9.6/alpine/docker-entrypoint.sh

@@ -36,8 +36,15 @@ if [ "$1" = 'postgres' ] && [ "$(id -u)" = '0' ]; then
 	mkdir -p /var/run/postgresql
 	chown -R postgres /var/run/postgresql
 	chmod g+s /var/run/postgresql
-
-	exec su-exec postgres "$BASH_SOURCE" "$@"
+    # Create the transaction log directory before initdb is run (below) so the directory is owned by the correct user
+    if [ "$POSTGRES_XLOG_DIR" ]; then
+        mkdir -p "$POSTGRES_XLOG_DIR"
+        chmod 700 "$POSTGRES_XLOG_DIR"
+        chown -R postgres "$POSTGRES_XLOG_DIR"
+        POSTGRES_INITDB_ARGS="$POSTGRES_INITDB_ARGS --xlogdir $POSTGRES_XLOG_DIR"
+    fi
+
+	exec gosu postgres "$BASH_SOURCE" "$@"
 fi
 
 if [ "$1" = 'postgres' ]; then

9.6/docker-entrypoint.sh

@@ -36,6 +36,13 @@ if [ "$1" = 'postgres' ] && [ "$(id -u)" = '0' ]; then
 	mkdir -p /var/run/postgresql
 	chown -R postgres /var/run/postgresql
 	chmod g+s /var/run/postgresql
+    # Create the transaction log directory before initdb is run (below) so the directory is owned by the correct user
+    if [ "$POSTGRES_XLOG_DIR" ]; then
+        mkdir -p "$POSTGRES_XLOG_DIR"
+        chmod 700 "$POSTGRES_XLOG_DIR"
+        chown -R postgres "$POSTGRES_XLOG_DIR"
+        POSTGRES_INITDB_ARGS="$POSTGRES_INITDB_ARGS --xlogdir $POSTGRES_XLOG_DIR"
+    fi
 
 	exec gosu postgres "$BASH_SOURCE" "$@"
 fi

docker-entrypoint.sh

@@ -36,6 +36,13 @@ if [ "$1" = 'postgres' ] && [ "$(id -u)" = '0' ]; then
 	mkdir -p /var/run/postgresql
 	chown -R postgres /var/run/postgresql
 	chmod g+s /var/run/postgresql
+    # Create the transaction log directory before initdb is run (below) so the directory is owned by the correct user
+    if [ "$POSTGRES_XLOG_DIR" ]; then
+        mkdir -p "$POSTGRES_XLOG_DIR"
+        chmod 700 "$POSTGRES_XLOG_DIR"
+        chown -R postgres "$POSTGRES_XLOG_DIR"
+        POSTGRES_INITDB_ARGS="$POSTGRES_INITDB_ARGS --xlogdir $POSTGRES_XLOG_DIR"
+    fi
 
 	exec gosu postgres "$BASH_SOURCE" "$@"
 fi