SugarCRM源码分析之loadComposer

        这里主要分析./include/utils/autoload.php中init方法里的加载composer相关方法，其主要作用是在自动加载时引入相关的composer类。

// 加载的composer文件
protected static $composerPaths = array(
    'include_paths' => 'vendor/composer/include_paths.php',
    'autoload_namespaces' => 'vendor/composer/autoload_namespaces.php',
    'autoload_psr4' => 'vendor/composer/autoload_psr4.php',
    'autoload_classmap' => 'vendor/composer/autoload_classmap.php',
);

// psr4命名空间存放，按多到少加载
public static $namespaceMapPsr4 = array();

// psr0命名空间存放
public static $namespaceMap = array();

        上面的三个变量作用这下面的几个composer方法。

public static function init() {
    ```
    self::loadComposerIncludePaths();
    self::loadComposerPsr4();
    self::loadComposerPsr0();
    ```
}

public static function loadComposerIncludePaths() {

    // 加载include_paths并加入get_include_path中，但是目前为空
    $includePaths = self::getIncludeReturn(self::$composerPaths['include_paths']);
    array_push($includePaths, get_include_path());
    set_include_path(join(PATH_SEPARATOR, $includePaths));
}

public static function loadComposerPsr4() {
    $map = self::getIncludeReturn(self::$composerPaths['autoload_psr4']);
    foreach ($map as $namespace => $paths) {
        if (is_array($paths)) {
            foreach ($paths as $path) {
                $path = self::normalizeFilePath($path);
                self::addNamespace($namespace, $path, 'psr4');
            }
        } else {
            $path = self::normalizeFilePath($paths);
            self::addNamespace($namespace, $path, 'psr4');
        }
    }
}

public static function loadComposerPsr0() {
    $map = self::getIncludeReturn(self::$composerPaths['autoload_namespaces']);
    foreach ($map as $namespace => $paths) {
        if (is_array($paths)) {
            foreach ($paths as $path) {
                $path = self::normalizeFilePath($path);
                self::addNamespace($namespace, $path, 'psr0');
            }
        } else {
            $path = self::normalizeFilePath($paths);
            self::addNamespace($namespace, $path, 'psr0');
        }
    }
}

public static function addNamespace($prefix, $dir, $type = 'psr0') {
    // select which map to use
    $map = ($type === 'psr4') ? 'namespaceMapPsr4' : 'namespaceMap';

    // enforce trailing \
    $prefix = rtrim($prefix, '\\') . '\\';

    // remove trailing / and normalize path
    $dir = rtrim(self::normalizeFilePath($dir), '/');

    // use a list of paths per prefix
    self::${$map}[$prefix][] = $dir;

    // The order of self::$namespace is important because the first match
    // will win. When registering new namespace dynamically we need to make
    // sure this array is ordered from more to less specific.

    // 从多到少排序
    // 这一步主要是在自动加载时循环数组从头开始，匹配到了便退出循环
    uksort(self::${$map}, function ($val1, $val2) {
        $level1 = substr_count($val1, '\\');
        $level2 = substr_count($val2, '\\');
        if ($level1 > $level2) {
            return -1;
        } elseif ($level1 < $level2) {
            return 1;
        } else {
            // if levels are the same, sort alphabetically for predictable result
            return strcasecmp($val1, $val2);
        }
    });
}

        可以看看./vendor/composer/目录下两个composer文件

// autoload_psr4.php @generated by Composer

$vendorDir = dirname(dirname(__FILE__));
$baseDir = dirname($vendorDir);

return array(
    'Sugarcrm\\Sugarcrm\\inc\\' => array($baseDir . '/include'),
    'Sugarcrm\\Sugarcrm\\custom\\inc\\' => array($baseDir . '/custom/include'),
    'Sugarcrm\\Sugarcrm\\custom\\' => array($baseDir . '/custom/src', $baseDir . '/custom'),
    'Sugarcrm\\Sugarcrm\\' => array($baseDir . '/src', $baseDir . '/'),
);


// autoload_namespaces.php @generated by Composer

$vendorDir = dirname(dirname(__FILE__));
$baseDir = dirname($vendorDir);

return array(
    'Elastica\\Test' => array($vendorDir . '/ruflin/elastica/test/lib'),
    'Elastica' => array($vendorDir . '/ruflin/elastica/lib'),
);