This option deprecates the DB_UNACCENT parameter

Author: Sameer Naik

Changelog.md

@@ -1,5 +1,8 @@
 # Changelog
 
+**latest**
+- added `DB_EXTENSION` configuration parameter
+
 **9.4-12**
 - removed use of single-user mode
 - added `DB_TEMPLATE` variable to specify the database template

README.md

@@ -15,6 +15,7 @@
   - [Creating databases](#creating-databases)
   - [Enabling unaccent extension](#enabling-unaccent-extension)
   - [Granting user access to a database](#granting-user-access-to-a-database)
+  - [Enabling extensions](#enabling-extensions)
   - [Creating replication user](#creating-replication-user)
   - [Setting up a replication cluster](#setting-up-a-replication-cluster)
   - [Creating a snapshot](#creating-a-snapshot)
@@ -198,6 +199,18 @@ docker run --name postgresql -itd --restart always \
 
 In the above example `dbuser` with be granted access to both the `dbname1` and `dbname2` databases.
 
+# Enabling extensions
+
+The image also packages the [postgres contrib module](http://www.postgresql.org/docs/9.4/static/contrib.html). A comma separated list of modules can be specified using the `DB_EXTENSION` parameter.
+
+```bash
+docker run --name postgresql -itd \
+  --env 'DB_NAME=db1,db2' --env 'DB_EXTENSION=unaccent,pg_trgm' \
+  sameersbn/postgresql:9.4-16
+```
+
+The above command enables the `unaccent` and `pg_trgm` modules on the databases listed in `DB_NAME`, namely `db1` and `db2`.
+
 ## Creating replication user
 
 Similar to the creation of a database user, a new PostgreSQL replication user can be created by specifying the `REPLICATION_USER` and `REPLICATION_PASS` variables while starting the container.

docker-compose.yml

@@ -12,6 +12,7 @@ PostgreSQL:
     - DB_TEMPLATE=
 
     - DB_UNACCENT=
+    - DB_EXTENSION=
 
     - REPLICATION_MODE=
     - REPLICATION_USER=

runtime/env-defaults

@@ -18,4 +18,6 @@ DB_USER=${DB_USER:-}
 DB_PASS=${DB_PASS:-}
 DB_TEMPLATE=${DB_TEMPLATE:-template1}
 
+DB_EXTENSION=${DB_EXTENSION:-}
+
 DB_UNACCENT=${DB_UNACCENT:-false}

runtime/functions

@@ -305,6 +305,20 @@ create_user() {
   fi
 }
 
+load_extensions() {
+  local database=${1?missing argument}
+
+  if [[ ${DB_UNACCENT} == true ]]; then
+    echo "‣ Loading unaccent extension..."
+    psql -U ${PG_USER} -d ${database} -c "CREATE EXTENSION IF NOT EXISTS unaccent;" >/dev/null 2>&1
+  fi
+
+  for extension in $(awk -F',' '{for (i = 1 ; i <= NF ; i++) print $i}' <<< "${DB_EXTENSION}"); do
+    echo "‣ Loading ${extension} extension..."
+    psql -U ${PG_USER} -d ${database} -c "CREATE EXTENSION IF NOT EXISTS ${extension};" >/dev/null 2>&1
+  done
+}
+
 create_database() {
   if [[ -n ${DB_NAME} ]]; then
     case $REPLICATION_MODE in
@@ -318,10 +332,7 @@ create_database() {
             psql -U ${PG_USER} -c "CREATE DATABASE \"${database}\" WITH TEMPLATE = \"${DB_TEMPLATE}\";" >/dev/null
           fi
 
-          if [[ ${DB_UNACCENT} == true ]]; then
-            echo "‣ Loading unaccent extension..."
-            psql -U ${PG_USER} -d ${database} -c "CREATE EXTENSION IF NOT EXISTS unaccent;" >/dev/null 2>&1
-          fi
+          load_extensions ${database}
 
           if [[ -n ${DB_USER} ]]; then
             echo "‣ Granting access to ${DB_USER} user..."