Skip to content
Branch: master
Find file History
dkarnutsch and pkubatrh Fix documentation for environment variables (#244)
* sti -> s2i

* fix docu also for 7.1 and 7.0
Latest commit 33c7ad2 May 28, 2019

README.md

PHP 7.0 Docker image

This container image includes PHP 7.0 as a S2I base image for your PHP 7.0 applications. Users can choose between RHEL and CentOS based builder images. The RHEL images are available in the Red Hat Container Catalog, the CentOS images are available on Docker Hub, and the Fedora images are available in Fedora Registry. The resulting image can be run using podman.

Note: while the examples in this README are calling podman, you can replace any such calls by docker with the same arguments

Description

PHP 7.0 available as container is a base platform for building and running various PHP 7.0 applications and frameworks. PHP is an HTML-embedded scripting language. PHP attempts to make it easy for developers to write dynamically generated web pages. PHP also offers built-in database integration for several commercial and non-commercial database management systems, so writing a database-enabled webpage with PHP is fairly simple. The most common use of PHP coding is probably as a replacement for CGI scripts.

This container image includes an npm utility, so users can use it to install JavaScript modules for their web applications. There is no guarantee for any specific npm or nodejs version, that is included in the image; those versions can be changed anytime and the nodejs itself is included just to make the npm work.

Usage

For this, we will assume that you are using the rhscl/php-70-rhel7 image, available via php:7.0 imagestream tag in Openshift. Building a simple php-test-app application in Openshift can be achieved with the following step:

```
oc new-app php:7.0~https://github.com/sclorg/s2i-php-container.git --context-dir=7.0/test/test-app/
```

The same application can also be built using the standalone S2I application on systems that have it available:

```
$ s2i build https://github.com/sclorg/s2i-php-container.git --context-dir=7.0/test/test-app/ rhscl/php-70-rhel7 php-sample-app
```

Accessing the application:

$ curl 127.0.0.1:8080

Environment variables

To set these environment variables, you can place them as a key value pair into a .s2i/environment file inside your source code repository.

The following environment variables set their equivalent property value in the php.ini file:

  • ERROR_REPORTING
    • Informs PHP of which errors, warnings and notices you would like it to take action for
    • Default: E_ALL & ~E_NOTICE
  • DISPLAY_ERRORS
    • Controls whether or not and where PHP will output errors, notices and warnings
    • Default: ON
  • DISPLAY_STARTUP_ERRORS
    • Cause display errors which occur during PHP's startup sequence to be handled separately from display errors
    • Default: OFF
  • TRACK_ERRORS
    • Store the last error/warning message in $php_errormsg (boolean)
    • Default: OFF
  • HTML_ERRORS
    • Link errors to documentation related to the error
    • Default: ON
  • INCLUDE_PATH
    • Path for PHP source files
    • Default: .:/opt/app-root/src:/opt/rh/rh-php70/root/usr/share/pear
  • PHP_MEMORY_LIMIT
    • Memory Limit
    • Default: 128M
  • SESSION_NAME
    • Name of the session
    • Default: PHPSESSID
  • SESSION_HANDLER
    • Method for saving sessions
    • Default: files
  • SESSION_PATH
    • Location for session data files
    • Default: /tmp/sessions
  • SESSION_COOKIE_DOMAIN
    • The domain for which the cookie is valid.
    • Default:
  • SESSION_COOKIE_HTTPONLY
    • Whether or not to add the httpOnly flag to the cookie
    • Default: 0
  • SESSION_COOKIE_SECURE
    • Specifies whether cookies should only be sent over secure connections.
    • Default: Off
  • SHORT_OPEN_TAG
    • Determines whether or not PHP will recognize code between tags
    • Default: OFF
  • DOCUMENTROOT
    • Path that defines the DocumentRoot for your application (ie. /public)
    • Default: /

The following environment variables set their equivalent property value in the opcache.ini file:

  • OPCACHE_MEMORY_CONSUMPTION
    • The OPcache shared memory storage size in megabytes
    • Default: 128
  • OPCACHE_REVALIDATE_FREQ
    • How often to check script timestamps for updates, in seconds. 0 will result in OPcache checking for updates on every request.
    • Default: 2

You can also override the entire directory used to load the PHP configuration by setting:

  • PHPRC
    • Sets the path to the php.ini file
  • PHP_INI_SCAN_DIR
    • Path to scan for additional ini configuration files

You can override the Apache MPM prefork settings to increase the performance for of the PHP application. In case you set some Cgroup limits, the image will attempt to automatically set the optimal values. You can override this at any time by specifying the values yourself:

  • HTTPD_START_SERVERS

    • The StartServers directive sets the number of child server processes created on startup.
    • Default: 8
  • HTTPD_MAX_REQUEST_WORKERS

    • The MaxRequestWorkers directive sets the limit on the number of simultaneous requests that will be served.
    • MaxRequestWorkers was called MaxClients before version httpd 2.3.13.
    • Default: 256 (this is automatically tuned by setting Cgroup limits for the container using this formula: TOTAL_MEMORY / 15MB. The 15MB is average size of a single httpd process.

    You can use a custom composer repository mirror URL to download packages instead of the default 'packagist.org':

    • COMPOSER_MIRROR
      • Adds a custom composer repository mirror URL to composer configuration. Note: This only affects packages listed in composer.json.
    • COMPOSER_INSTALLER
    • COMPOSER_ARGS
      • Adds extra arguments to the composer install command line (for example --no-dev).

Source repository layout

You do not need to change anything in your existing PHP project's repository. However, if these files exist they will affect the behavior of the build process:

  • composer.json

    List of dependencies to be installed with composer. The format is documented here.

  • .htaccess

    In case the DocumentRoot of the application is nested within the source directory /opt/app-root/src, users can provide their own Apache .htaccess file. This allows the overriding of Apache's behavior and specifies how application requests should be handled. The .htaccess file needs to be located at the root of the application source.

Hot deploy

In order to immediately pick up changes made in your application source code, you need to run your built image with the OPCACHE_REVALIDATE_FREQ=0 environment variable passed to Podman -e run flag:

$ podman run -e OPCACHE_REVALIDATE_FREQ=0 -p 8080:8080 php-app

To change your source code in running container, use Podman's exec) command:

podman exec -it <CONTAINER_ID> /bin/bash

After you Podman exec into the running container, your current directory is set to /opt/app-root/src, where the source code is located.

Extending image

Not only content, but also startup scripts and configuration of the image can be extended using source-to-image.

The structure of the application can look like this:

Folder name Description
./httpd-cfg Can contain additional Apache configuration files (*.conf)
./httpd-ssl Can contain own SSL certificate (in certs/ subdirectory) and key (in private/ subdirectory)
./php-pre-start Can contain shell scripts (*.sh) that are sourced before httpd is started
./php-post-assemble Can contain shell scripts (*.sh) that are sourced at the end of assemble script
./ Application source code

See also

Dockerfile and other sources are available on https://github.com/sclorg/s2i-php-container. In that repository you also can find another versions of Python environment Dockerfiles. Dockerfile for CentOS is called Dockerfile, Dockerfile for RHEL7 is called Dockerfile.rhel7, for RHEL8 it's Dockerfile.rhel8 and the Fedora Dockerfile is called Dockerfile.fedora.

Security Implications

-p 8080:8080

 Opens  container  port  8080  and  maps it to the same port on the Host.
You can’t perform that action at this time.