Adding the possibility for change easily the php version of the WP server

Author: dianjuar

docker-compose.yml

@@ -15,7 +15,12 @@ services:
      - wp_server
 
   wp_server:
-    build: ./docker-images/php/
+    build: 
+      context: ./docker-images/php/
+      args:
+        PHP_VERSION: 7.1
+        # PHP_VERSION: 7.0
+        # PHP_VERSION: 5.6
     user: ${UID}:www-data
     container_name: wp_server
     volumes:

docker-images/php/Dockerfile

@@ -1,4 +1,6 @@
-FROM php:7.1-fpm-alpine
+ARG PHP_VERSION
+
+FROM php:"$PHP_VERSION"-fpm-alpine
 
 # docker-entrypoint.sh dependencies
 RUN apk add --no-cache \