From 993b16471e5aba4f6f481f9cac56b6cac0dea7b9 Mon Sep 17 00:00:00 2001
From: Sameer Naik <sameer@damagehead.com>
Date: Mon, 27 Jul 2015 15:02:04 +0530
Subject: [PATCH] added master/slave replication support

Example,

Start master:

```bash
docker run -it --rm --name mariadb-master \
  -e 'MARIADB_USER=root' -e 'MARIADB_PASSWORD=password' \
  -e 'MARIADB_DATABASE=newdatabase' \
  -e 'REPLICATION_MODE=master' -e 'REPLICATION_USER=slave' -e 'REPLICATION_PASSWORD=slavepassword' \
  bitnami/mariadb
```

Start Slave:

```bash
docker run -it --rm --name mariadb-slave \
  --link mariadb-master:mariadb-master \
  -e 'MARIADB_USER=root' -e 'MARIADB_PASSWORD=password' \
  -e 'MARIADB_DATABASE=newdatabase' -e 'REPLICATION_MODE=slave' \
  bitnami/mariadb
```
---
 bitnami/mariadb/bitnami-utils-custom.sh | 42 +++++++++++++++++++++++++
 bitnami/mariadb/entrypoint.sh           |  2 ++
 2 files changed, 44 insertions(+)

diff --git a/bitnami/mariadb/bitnami-utils-custom.sh b/bitnami/mariadb/bitnami-utils-custom.sh
index 02a5c6dcab36..3fa48ec9b87e 100644
--- a/bitnami/mariadb/bitnami-utils-custom.sh
+++ b/bitnami/mariadb/bitnami-utils-custom.sh
@@ -1,6 +1,14 @@
 # MariaDB Utility functions
 PROGRAM_OPTIONS="--defaults-file=$BITNAMI_APP_DIR/my.cnf --log-error=$BITNAMI_APP_DIR/logs/mysqld.log --basedir=$BITNAMI_APP_DIR --datadir=$BITNAMI_APP_DIR/data --plugin-dir=$BITNAMI_APP_DIR/lib/plugin --user=$BITNAMI_APP_USER --socket=$BITNAMI_APP_DIR/tmp/mysql.sock --lower-case-table-names=1"
 
+if [ "$REPLICATION_MODE" ]; then
+  SERVER_ID=${SERVER_ID:-$RANDOM}
+  PROGRAM_OPTIONS+=" --server-id=$SERVER_ID --log-bin=mysql-bin --binlog-format=ROW"
+  if [ "$REPLICATION_MODE" = "slave" ]; then
+    PROGRAM_OPTIONS+=" --relay-log=mysql-relay-bin ${MARIADB_DATABASE:+--replicate-do-db=$MARIADB_DATABASE}"
+  fi
+fi
+
 initialize_database() {
     echo "==> Initializing MySQL database..."
     echo ""
@@ -46,6 +54,40 @@ create_mysql_user() {
   echo "DROP DATABASE IF EXISTS test ; " >> /tmp/init_mysql.sql
 }
 
+configure_replication() {
+  case "$REPLICATION_MODE" in
+    master)
+      if [ "$REPLICATION_USER" ]; then
+        echo "==> Creating replication user $REPLICATION_USER..."
+        echo ""
+
+        echo "GRANT REPLICATION SLAVE ON *.* TO '$REPLICATION_USER'@'%' IDENTIFIED BY '$REPLICATION_PASSWORD';" >> /tmp/init_mysql.sql
+        echo "FLUSH PRIVILEGES ;" >> /tmp/init_mysql.sql
+      fi
+      ;;
+    slave)
+      echo ""
+      echo "==> Setting up MariaDB slave..."
+
+      echo "==> Trying to fetch MariaDB master connection parameters from the mariadb-master link..."
+      MASTER_HOST=${MASTER_HOST:-$MARIADB_MASTER_PORT_3306_TCP_ADDR}
+      MASTER_USER=${MASTER_USER:-$MARIADB_MASTER_ENV_MARIADB_USER}
+      MASTER_PASSWORD=${MASTER_PASSWORD:-$MARIADB_MASTER_ENV_MARIADB_PASSWORD}
+      REPLICATION_USER=${REPLICATION_USER:-$MARIADB_MASTER_ENV_REPLICATION_USER}
+      REPLICATION_PASSWORD=${REPLICATION_PASSWORD:-$MARIADB_MASTER_ENV_REPLICATION_PASSWORD}
+
+      echo "==> Creating a data snapshot..."
+      mysqldump -u$MASTER_USER ${MASTER_PASSWORD:+-p$MASTER_PASSWORD} -h $MASTER_HOST $MARIADB_DATABASE --master-data >> /tmp/init_mysql.sql
+
+      echo "==> Setting the master configuration..."
+      echo "CHANGE MASTER TO MASTER_HOST='$MASTER_HOST', MASTER_USER='$REPLICATION_USER', MASTER_PASSWORD='$REPLICATION_PASSWORD'" >> /tmp/init_mysql.sql
+
+      echo "==> Starting the slave..."
+      echo "START SLAVE ;" >> /tmp/init_mysql.sql
+      ;;
+  esac
+}
+
 print_mysql_password() {
   if [ -z $MARIADB_PASSWORD ]; then
     echo "**none**"
diff --git a/bitnami/mariadb/entrypoint.sh b/bitnami/mariadb/entrypoint.sh
index 72e59afda1bf..92a685f10733 100755
--- a/bitnami/mariadb/entrypoint.sh
+++ b/bitnami/mariadb/entrypoint.sh
@@ -32,6 +32,8 @@ if [ "$1" = 'mysqld.bin' ]; then
 
     create_mysql_user
 
+    configure_replication
+
     print_app_credentials $BITNAMI_APP_NAME $MARIADB_USER `print_mysql_password` `print_mysql_database`
   else
     print_container_already_initialized $BITNAMI_APP_NAME