extensions.md

PHP extensions

The images come in 2 types:

• the slim images contain only the basic extensions: you would typically use them in a Dockerfile that compiles the extensions your application needs;
• the fat images contain the most commonly used extensions, ready to be enabled with environment variables: you would typically use them in a local or CI environment.

Extensions of the slim images

These extensions are enabled by default in the slim images: calendar ctype curl date dom exif fileinfo filter ftp gettext iconv json mbstring opcache openssl pcntl pcre PDO Phar posix readline Reflection session shmop SimpleXML sockets sodium SPL sysvmsg sysvsem sysvshm tokenizer xml xmlreader xmlwriter xsl zip

This list can be outdated, you can verify it with: docker run --rm thecodingmachine/php:8.4-v5-slim-cli php -m

Extensions of the fat images

Enabled by default (in addition to the extensions of the slim images): apcu hash iconv igbinary mysqli mysqlnd pdo_mysql redis soap xsl zlib

Available (can be enabled with environment variables): amqp ast bcmath blackfire bz2 dba decimal ds enchant exif excimer ffi mailparse msgpack gd gettext gmp gnupg grpc igbinary imagick imap inotify intl ldap lz4 mcrypt memcached mongodb odbc opentelemetry pcov pdo_dblib pdo_odbc pdo_pgsql pdo_sqlite pgsql pspell rdkafka shmop snmp sockets sqlite3 swoole tidy uploadprogress uuid xdebug xmlrpc xsl yaml zstd

This list can be outdated, you can verify it with: docker run --rm thecodingmachine/php:8.4-v5-cli php -m

Notes:

• ev is not available in PHP 8.1+
• mcrypt is deprecated and its usage is discouraged: it is provided for legacy applications only
• imagick supports SVG, WMF, DjVu and OpenEXR images in addition to the common formats. If you process untrusted images, you can restrict the allowed formats in the ImageMagick policy (/etc/ImageMagick-6/policy.xml)
• The extensions required by an enabled extension are enabled with it, even if they are disabled: igbinary and msgpack for memcached, igbinary for redis, mbstring for mailparse, curl and mysqlnd for swoole, mysqlnd for mysqli and pdo_mysql
• To debug or profile your application with xdebug or blackfire, see Debugging and profiling

Enabling/disabling extensions in the fat images

Use the PHP_EXTENSION_<extension name> environment variables:

services:
  my_app:
    image: thecodingmachine/php:8.4-v5-apache
    environment:
      # Enable the PostgreSQL extension
      PHP_EXTENSION_PGSQL: 1
      # Disable the Mysqli extension (enabled by default)
      PHP_EXTENSION_MYSQLI: 0

As an alternative, the PHP_EXTENSIONS variable lists the extensions to enable:

PHP_EXTENSIONS=pgsql gettext imap

Compiling extensions in the slim images

With a slim image, the PHP_EXTENSIONS ARG lists the extensions to install during the build:

ARG PHP_EXTENSIONS="apcu mysqli pdo_mysql redis soap"
FROM thecodingmachine/php:8.4-v5-slim-apache
# The build automatically downloads and compiles the extensions
# (thanks to an ONBUILD hook in the slim image)

Beware:

• The ARG PHP_EXTENSIONS instruction must be written before the FROM. This is not a typo.
• ARG PHP_EXTENSIONS="" is not the same as ENV PHP_EXTENSIONS="".
• ARG PHP_EXTENSION_<extension name> (like the environment variables of the fat images) is not supported.
• With a multi-stage build, the ARG must be at the very top of the file (before the first FROM):

# The PHP_EXTENSIONS ARG applies to the slim image
ARG PHP_EXTENSIONS="apcu mysqli pdo_mysql soap"

FROM thecodingmachine/php:8.4-v5-apache-node24 AS builder

COPY --chown=docker:docker sources/web .
RUN composer install &&\
    yarn install &&\
    yarn build

# The slim image builds the extensions listed at the very top of the file
FROM thecodingmachine/php:8.4-v5-slim-apache

ENV APP_ENV=prod \
    APACHE_DOCUMENT_ROOT=public/

COPY --from=builder /var/www/html .

In this example, the fat image runs the yarn build, and the result is copied in a slim image that does not contain NodeJS and contains only the required extensions.