Managing Dependencies with Composer (Seattle PHP User Group October 2013)

Does your project rely on third-party code? Does your company share code between multiple projects? If so, you have dealt with dependencies. Traditionally, there have been many ways to manage dependencies for PHP projects: PEAR, copying and pasting, ZIP archives, Subversion exports, git submodules, or complicated build scripts. Composer, a dependency manager for PHP, aims to make the whole process more streamlined. Learn how Composer can be used to manage third-party packages, how to create and distribute your own Composer packages, and how Composer can change the way you think about code reuse.

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1. Managing Dependencies with Composer Seattle PHP User Group October 10th, 2013
2. @beausimensen  simensen  beau.io  Beau Simensen
3. dflydev 
5. Dependency Manager for PHP
6. Dependencies Are External Requirements
7. Traditionally, Managing Dependencies Has Not Been Trivial
8. { “name”: “acme/my-project”, “description”: “Acme’s My Project”, “license”: “MIT”, “require”: { “silex/silex”: “1.1.*” }, “autoload”: { “psr-0”: { “Acme\\MyProject\\”: “src” } } }
9. Autoloading Versioning Packaging
10. Autoloading Versioning Packaging
11. // // life without autoloading // require “../vendor/whizbang/classes.php”; $service = new Acme\WhizBang\Thing()
12. // // life WITH autoloading // $service = new Acme\WhizBang\Thing()
13. // // Example autoloader that will load any fully qualified // class name in the Foo\Bar namespace. If someone tries // to load Foo\Bar\Baz, this autoloader will attempt to // include a file named src/Baz.php which is expected to // define Foo\Bar\Baz. // spl_autoload_register(function ($fqcn) { $prefix = 'Foo\\Bar\\'; $class = ltrim($class, '\\'); if (strncmp($prefix, $class, strlen($prefix)) === 0) { $relative = substr($class, strlen($prefix)); $file = __DIR__ . '/src/' . str_replace('\\', '/', $relative) . '.php'; if (is_readable($file)) { include $file; } } });
14. // // life when everyone has their own custom // autoloader bootstrap, registration classes // and manually configuring class loaders // require “../vendor/whizbang/bootstrap.php”; require “../vendor/awesomesoft/bootstrap.php”; require “../vendor/lessawesome/bootstrapper.php”; require “../vendor/ultraframework/classloader.php”; LessAwesome\BootStrapper::register(); UltraFramework\ClassLoader::register(array( “\\Acme\\MyApp\\” = “../src” ));
15. Composer Provides a Configurable Autoloader
16. Each Package Can Configure Its Own Autoloader Rules
17. require “vendor/autoload.php”;
18. Autoloading Versioning Packaging
19. Semantic Versioning http://semver.org/
20. MAJOR.MINOR.PATCH Which number do you increment and why?
21. MAJOR.MINOR.PATCH When you make API incompatible changes
22. MAJOR.MINOR.PATCH When you add backwards-compatible functionality
23. MAJOR.MINOR.PATCH When you make backwards-compatible bug fixes
24. Pre-Release Identifiers (Composer “Stability”) •1.0.0-alpha •1.0.0-beta.1 •1.0.0-RC2 •1.0.0 (stable)
25. Exact Versions 1.0.2
26. Ranges >=1.0,<2.0
27. Wildcards 1.0.*
28. Next Significant Release Tilde Operator
29. Next Significant Release ~1.2 >=1.2,<2.0
30. Next Significant Release ~1.2.3 >=1.2.3,<1.3
31. Let’s You Know What You Are Getting Into
32. Safe 1.3.* Only get bug fixes.
33. Reasonably Safe 1.* Get bug fixes and new features.
34. Crazy Sauce * Composer allows this, but don’t. Just don’t.
35. Other Version Schemes Can Be Used But don’t expect Composer to read your mind and do anything smart with them.
36. Autoloading Versioning Packaging
37. Any VCS Repository Can Be Treated like a Composer Package
38. Composer Treats Tags as Versions for VCS Repositories
39. Composer Treats Branches as @dev for VCS Repositories
40. GitHub and BitBucket Serve Tags as Archives
41. silex-1.0.1.tar.gz
42. • Integration into existing VCS workflow • Packaging is as simple as tagging and pushing • Hosting can be handled automatically by GitHub and BitBucket VCS Repository Benefits
43. https://packagist.org
44. Over 17,000 Packages
46. Basic Usage Managing dependencies for a project.
47. Install Composer http://getcomposer.org/download
48. $ curl -sS https://getcomposer.org/installer | php $ php composer.phar --version
49. $ chmod 755 composer.phar $ mv composer.phar ~/bin/composer $ composer --version
50. $ composer diag Check for common errors.
51. composer.json
52. { “name”: “acme/my-project”, “description”: “Acme’s My Project”, “license”: “MIT”, “require”: { “silex/silex”: “1.1.*” }, “autoload”: { “psr-0”: { “Acme\\MyProject\\”: “src” } } }
53. { “name”: “acme/my-project”, “description”: “Acme’s My Project”, “license”: “MIT”, “require”: { “silex/silex”: “1.1.*” }, “autoload”: { “psr-0”: { “Acme\\MyProject\\”: “src” } } }
54. vendor/project-name
55. { “name”: “acme/my-project”, “description”: “Acme’s My Project”, “license”: “MIT”, “require”: { “silex/silex”: “1.1.*” }, “autoload”: { “psr-0”: { “Acme\\MyProject\\”: “src” } } }
56. { “name”: “acme/my-project”, “description”: “Acme’s My Project”, “license”: “MIT”, “require”: { “silex/silex”: “1.1.*” }, “autoload”: { “psr-0”: { “Acme\\MyProject\\”: “src” } } }
57. $ composer validate Checks composer.json for errors.
58. Autoload Configuration
59. PSR-0 PHP Framework Interoperability Group http://php-fig.com
60. PSR-0’s Big Ideas • 1:1 mapping between fully qualified class names and the filesystem (one file / class) • Embrace namespaces • Support some legacy naming conventions
61. { “autoload”: { “psr-0”: { “Acme\\MyProject\\”: “src” } } }
62. { “autoload”: { “psr-0”: { “Acme\\MyProject\\”: “src” } } } $bar = new Acme\MyProject\Foo\Bar();
63. { “autoload”: { “psr-0”: { “Acme\\MyProject\\”: “src” } } } $bar = new Acme\MyProject\Foo\Bar(); src/Acme/MyProject/Foo/Bar.php
64. PSR-4 PHP Framework Interoperability Group (Coming Soon!) http://php-fig.com
65. PSR-4’s Big Ideas • 1:1 mapping between a part of fully qualified class names and the filesystem (one file / class) • Minimize the number of extra directories that PSR-0 required • Drop support for legacy naming conventions that PSR-0 supported
66. { “autoload”: { “psr-4”: { “Acme\\MyProject\\”: “src” } } }
67. { “autoload”: { “psr-4”: { “Acme\\MyProject\\”: “src” } } } $bar = new Acme\MyProject\Foo\Bar();
68. { “autoload”: { “psr-4”: { “Acme\\MyProject\\”: “src” } } } $bar = new Acme\MyProject\Foo\Bar(); src/Foo/Bar.php
69. // // Example autoloader that will load any fully qualified // class name in the Foo\Bar namespace. If someone tries // to load Foo\Bar\Baz, this autoloader will attempt to // include a file named src/Baz.php which is expected to // define Foo\Bar\Baz. // // This is PSR-4 in a nutshell. // spl_autoload_register(function ($fqcn) { $prefix = 'Foo\\Bar\\'; $class = ltrim($class, '\\'); if (strncmp($prefix, $class, strlen($prefix)) === 0) { $relative = substr($class, strlen($prefix)); $file = __DIR__ . '/src/' . str_replace('\\', '/', $relative) . '.php'; if (is_readable($file)) { include $file; } } });
70. Files Explicitly include certain files
71. { “autoload”: { “files”: [ “src/foo.class.php”, “src/bar.class.php” ] } }
72. { “autoload”: { “files”: [“src/functions.php”] } }
73. { “autoload”: { “files”: [“src/autoload.php”] } }
74. Classmap Generates a single key => value map classes found by scanning for .php and .inc files in specified directories
75. { “autoload”: { “classmap”: [ “src/includes/”, “resources/config.php” ] } }
76. composer.lock
77. $ composer install If composer.lock does not exist, it installs from composer.json and creates composer.lock. If composer.lock exists, it installs from there.
78. $ composer update Installs dependencies from composer.json and creates or updates composer.lock.
79. Stability
80. { “require”: { “silex/silex”: “~1.1@dev”, “symfony/http-foundation”: “@beta” } }
81. Stability Comes From Root Project
82. { “require”: { “silex/silex”: “~1.1@dev”, “symfony/http-foundation”: “@beta” }, “minimum-stability”: “alpha” }
83. Library Project Usage Maintaining a reusable Composer package.
84. Version Constraint Considerations
85. If the dependency specifications are too tight, you are in danger of version lock (the inability to upgrade a package without having to release new versions of every dependent package). — Semantic Versioning http://semver.org/
86. If dependencies are specified too loosely, you will inevitably be bitten by version promiscuity (assuming compatibility with more future versions than is reasonable). — Semantic Versioning http://semver.org/
87. { “require”: { “dflydev/doctrine-orm-service-provider”: “1.0.*”, “silex/silex”: “1.1.*”, “pimple/pimple”: “1.1.*”, “doctrine/orm”: “2.4.*” } } { “name”: “silex/silex”, “require”: { “pimple/pimple”: “1.*” } } { “name”: “dflydev/doctrine-orm-service-provider”, “require”: { “pimple/pimple”: “1.*”, “doctrine/orm”: “~2.3” } }
88. Branch Stability dev-master and @dev
89. { “require”: { “silex/silex”: “1.1@dev”, “pimple/pimple”: “dev-master” } }
90. Branch Versions Composer automatically detects numbered branches as development versions. Branch named 2.0 is treated as 2.0.*@dev
91. Branch Aliases Composer can alias a named branch to a specific development version. Branch named master is treated as 2.0.*@dev
92. { “extra”: { “branch-alias”: { “dev-master”: “2.0.x-dev” } } }
93. When starting a new library that is to be distributed via Packagist / Composer, be SURE to set up your dev-master branch alias. — Don Gilbert https://twitter.com/dilbert4life/status/380137097614458881
94. • It is best to rely on version detection using tags and branches • There is a version key but do not use it • Composer skips branches and tags that do not have composer.json so you won’t magically get legacy versions VCS Repository Version Detection Gotchas
95. Dev Dependencies
96. { “require-dev”: { “phpunit/phpunit”: “3.7.*”, “acme/specialized”: “1.*” } }
97. Solver
98. Solver A C B I H 1.* ~2.3 D F E G 1.* 1.4.* >=2.3.5 J K 1.4.10
99. Questions? #composer #sculpin #silex-php #dflydev @beausimensen 