摘要：本質是將為的請求轉化為追加的組內請求，對應的匿名函數依然是為的請求假如為，則返回優先從設置里面取值，沒有則生成單數形式的字符串，并將字符替換為小結資源類型的構造，實際上會被轉化為構造多個默認資源的路由，本質依然是基本構造

構造方法有：
Route::get、Route::post、Route::put、Route::patch、Route::delete、Route::options、Route::any、Route::match、Route::resource、Route::resources、Route::group

Route::get("foo", function () {
    // 基本方式
});
Route::match(["get", "post"], "/", function () {
    // 基本方式
});
Route::any("foo", function () {
    // 基本方式
});

Route::get("posts/{post}/comments/{comment}", function ($postId, $commentId) {
    // 必選路由參數
});

Route::get("user/{name?}", function ($name = "John") {
    // 可選路由參數
});

Route::get("user/{id}/{name}", function ($id, $name) {
    // 正則表達式約束
})->where(["id" => "[0-9]+", "name" => "[a-z]+"]);

// 全局約束 RouteServiceProvider 的 boot 方法
public function boot()
{
    Route::pattern("id", "[0-9]+"); 
    parent::boot();
}
Route::get("user/{id}", function ($id) {
    // 僅在 {id} 為數字時執行...
});

Route::get("user/profile", function () {
    // 命名路由
})->name("profile");
Route::get("user/profile", "UserController@showProfile")->name("profile");
為命名路由生成:
// 生成 URL...
$url = route("profile");
// 生成重定向...
return redirect()->route("profile");

// 路由組
Route::group(["middleware" => "auth"], function () {
    Route::get("/", function ()    {
        // 使用 `Auth` 中間件
    });

    Route::get("user/profile", function () {
        // 使用 `Auth` 中間件
    });
});

命名空間|子域名路由|路由前綴
Route::group(["namespace" => "Admin","domain" => "{account}.myapp.com","prefix" => "admin"], function () {
    // 在 "AppHttpControllersAdmin" 命名空間下，子域名為{account}.myapp.com，路由前綴匹配 "/admin" 的控制器
});

Route::resource("photo", "PhotoController", ["except" => ["create", "store", "update", "destroy"], "names" => ["create" => "photo.build"],"middleware" => []);

路由模型綁定
隱式綁定#
Laravel 會自動解析定義在路由或控制器方法（方法包含和路由片段匹配的已聲明類型變量）中的 Eloquent 模型
Route::get("api/users/{user}", function (AppUser $user) {
    return $user->email;
});
顯式綁定
RouteServiceProvider 類中的 boot 方法
public function boot()
{
    parent::boot();    
    Route::model("user", AppUser::class);
}
Route::get("profile/{user}", function (AppUser $user) {
    //
});

自定義解析邏輯
public function boot()
{
    parent::boot();    
    Route::bind("user", function ($value) {
        return AppUser::where("name", $value)->first();
    });
}

基本有以下幾種形式：uri 分為是否帶有參數， action 分為匿名函數或者 Controller@Method 形式，可能還會帶一些其他的前置操作

Route::get、Route::post、Route::put、Route::patch、Route::delete、Route::options、Route::any、Route::match

以上的構造方法本質是一樣的，區別在于第一個參數

public function get($uri, $action = null)
{
    return $this->addRoute(["GET", "HEAD"], $uri, $action);
}
protected function addRoute($methods, $uri, $action)
{
    // 創建 $route(IlluminateRoutingRoute) 對象并加入到集合(IlluminateRoutingRouteCollection 路由集合輔助類)里，再返回 $route
    return $this->routes->add($this->createRoute($methods, $uri, $action));
}
protected function createRoute($methods, $uri, $action)
{
    // $action 若為 Controller@Method|["uses"=>Controller@Method] 形式
    if ($this->actionReferencesController($action)) {
        $action = $this->convertToControllerAction($action);
    }

    $route = $this->newRoute(
        $methods, $this->prefix($uri), $action
    );
    // 如果前綴條件棧不為空，則對 $route 進行相應的設置
    if ($this->hasGroupStack()) {
        $this->mergeGroupAttributesIntoRoute($route);
    }
    // 將 where 前置條件注入到 $route 對象
    $this->addWhereClausesToRoute($route);

    return $route;
}
protected function actionReferencesController($action)
{
    if (! $action instanceof Closure) {
        return is_string($action) || (isset($action["uses"]) && is_string($action["uses"]));
    }

    return false;
}
protected function convertToControllerAction($action)
{
    if (is_string($action)) {
        $action = ["uses" => $action];
    }
    // 嘗試加入前置條件 namespace
    if (! empty($this->groupStack)) {
        $action["uses"] = $this->prependGroupNamespace($action["uses"]);
    }
    // 通過控制器來獲取 action
    $action["controller"] = $action["uses"];
    // 類似：["controller"=>"namespaceController@Method", "uses"=>"namespaceController@Method"]
    return $action;
}
// $uri 嘗試增加前置條件 prefix(group 組中的 prefix，對應給下面的所有路由增加)
protected function prefix($uri)
{
    return trim(trim($this->getLastGroupPrefix(), "/")."/".trim($uri, "/"), "/") ?: "/";
}
public function getLastGroupPrefix()
{
    if (! empty($this->groupStack)) {
        $last = end($this->groupStack);

        return isset($last["prefix"]) ? $last["prefix"] : "";
    }

    return "";
}
protected function newRoute($methods, $uri, $action)
{
    return (new Route($methods, $uri, $action))
                ->setRouter($this)
                ->setContainer($this->container);
}
// new Route
public function __construct($methods, $uri, $action)
{
    $this->uri = $uri;
    $this->methods = (array) $methods;
    $this->action = $this->parseAction($action);

    if (in_array("GET", $this->methods) && ! in_array("HEAD", $this->methods)) {
        $this->methods[] = "HEAD";
    }
    // 再嘗試給 uri 多帶帶的加入 prefix 前綴 
    if (isset($this->action["prefix"])) {
        $this->prefix($this->action["prefix"]);
    }
}
protected function parseAction($action)
{
    // 委托 RouteAction action 輔助類進行解析
    return RouteAction::parse($this->uri, $action);
}
public static function parse($uri, $action)
{
    if (is_null($action)) {
        return static::missingAction($uri); // 拋異常
    }
    // 匿名函數
    if (is_callable($action)) {
        return ["uses" => $action];
    }
    elseif (! isset($action["uses"])) {
        $action["uses"] = static::findCallable($action);
    }
    // 如果 $action["uses"] 類似 Controller 形式，則嘗試構造為 Controller@__invoke 形式，即沒有指定方法時調用 __invoke 方法
    if (is_string($action["uses"]) && ! Str::contains($action["uses"], "@")) {
        $action["uses"] = static::makeInvokable($action["uses"]);
    }

    return $action;
}
 protected static function findCallable(array $action)
{
    // 嘗試從 $action 數組找到第一個滿足可調用且為數字鍵的值作為 $action 返回
    return Arr::first($action, function ($value, $key) {
        return is_callable($value) && is_numeric($key);
    });
}
public function hasGroupStack()
{
    return ! empty($this->groupStack);
}
protected function mergeGroupAttributesIntoRoute($route)
{
    $route->setAction($this->mergeWithLastGroup($route->getAction()));
}
public function mergeWithLastGroup($new)
{
    // 使用上一層的 groupStack 設置
    return RouteGroup::merge($new, end($this->groupStack));
}
protected function addWhereClausesToRoute($route)
{
    $route->where(array_merge(
        $this->patterns, isset($route->getAction()["where"]) ? $route->getAction()["where"] : []
    ));

    return $route;
}
// 返回 IlluminateRoutingRoute 對象
public function add(Route $route)
{
    // 設置路由以何種方式放入路由集合，待后續按此種方式來獲取
    $this->addToCollections($route);
    $this->addLookups($route);
    return $route;
}
protected function addToCollections($route)
{
    $domainAndUri = $route->domain().$route->uri();
    // 表面可以通過 method 和 uri 來獲取路由
    foreach ($route->methods() as $method) {
        $this->routes[$method][$domainAndUri] = $route;
    }    
    $this->allRoutes[$method.$domainAndUri] = $route;
}
protected function addLookups($route)
{
    $action = $route->getAction();
    // 如果前置條件棧設置了 as ，則將 $route 注入到 $this->nameList，即可以通過名字來獲取路由
    if (isset($action["as"])) {
        $this->nameList[$action["as"]] = $route;
    }        
    if (isset($action["controller"])) {
        $this->addToActionList($action, $route);
    }
}
protected function addToActionList($action, $route)
{
    // 表示可以通過控制器獲取路由
    $this->actionList[trim($action["controller"], "")] = $route;
}

流程小結(創建 route ，并將加入到路由集合里進行統一的管理)

根據 action 的形式和前置條件，或轉為數組(["use"=> Clause|namespaceController@Method])，或為匿名函數

根據前置條件，或將組 uri 加前綴

創建 route 對象,并將 action 統一為數組，再進行一些其他設置

若存在前置條件，則加入到 route 對象的 action 數組

route 對象加入 where 條件

Route::group

public function group(array $attributes, $routes)
{
    $this->updateGroupStack($attributes);

    $this->loadRoutes($routes);

    array_pop($this->groupStack);
}
protected function updateGroupStack(array $attributes)
{
    if (! empty($this->groupStack)) {
        $attributes = RouteGroup::merge($attributes, end($this->groupStack));
    }

    $this->groupStack[] = $attributes;
}
protected function loadRoutes($routes)
{
    if ($routes instanceof Closure) {
        $routes($this);     // 注意：每個匿名函數都會有 router 對象
    } else {
        $router = $this;

        require $routes;
    }
}

小結

主要通過設置前置條件棧($groupStack)，然后運用到組內的所有成員，本質還是基本構造

Route::resource、Route::resources

public function resource($name, $controller, array $options = [])
{
    if ($this->container && $this->container->bound(ResourceRegistrar::class)) {
        $registrar = $this->container->make(ResourceRegistrar::class);
    } else {
        $registrar = new ResourceRegistrar($this);
    }

    $registrar->register($name, $controller, $options);
}
public function __construct(Router $router)
{
    $this->router = $router;
}
public function register($name, $controller, array $options = [])
{
    if (isset($options["parameters"]) && ! isset($this->parameters)) {
        $this->parameters = $options["parameters"];
    }

    if (Str::contains($name, "/")) {
        $this->prefixedResource($name, $controller, $options);

        return;
    }

    $base = $this->getResourceWildcard(last(explode(".", $name)));
    // ["index", "create", "store", "show", "edit", "update", "destroy"]
    $defaults = $this->resourceDefaults;
    // 生成相應條件下的路由
    foreach ($this->getResourceMethods($defaults, $options) as $m) {
        $this->{"addResource".ucfirst($m)}($name, $base, $controller, $options);
    }
}
protected function prefixedResource($name, $controller, array $options)
{
    list($name, $prefix) = $this->getResourcePrefix($name);
    // $me 為 router 對象。本質是將 $name 為 "xx/yy/zz" 的 resource 請求轉化為 groupStack 追加 ["prefix"=>"xx/yy"] 的 group 組內請求，對應的匿名函數依然是 $name 為 "zz" 的 resource 請求
    $callback = function ($me) use ($name, $controller, $options) {
        $me->resource($name, $controller, $options);
    };

    return $this->router->group(compact("prefix"), $callback);
}
protected function getResourcePrefix($name)
{
    $segments = explode("/", $name);

    $prefix = implode("/", array_slice($segments, 0, -1));
    // 假如 $name 為 "xx/yy/zz"， 則返回 ["zz", "xx/yy"]
    return [end($segments), $prefix];
}
// 優先從設置里面取值，沒有則生成單數形式的字符串，并將字符 "-" 替換為 "_"
public function getResourceWildcard($value)
{
    if (isset($this->parameters[$value])) {
        $value = $this->parameters[$value];
    } elseif (isset(static::$parameterMap[$value])) {
        $value = static::$parameterMap[$value];
    } elseif ($this->parameters === "singular" || static::$singularParameters) {
        $value = Str::singular($value);
    }

    return str_replace("-", "_", $value);
}
protected function getResourceMethods($defaults, $options)
{
    if (isset($options["only"])) {
        return array_intersect($defaults, (array) $options["only"]);
    } elseif (isset($options["except"])) {
        return array_diff($defaults, (array) $options["except"]);
    }

    return $defaults;
}
protected function addResourceIndex($name, $base, $controller, $options)
{
    $uri = $this->getResourceUri($name);

    $action = $this->getResourceAction($name, $controller, "index", $options);

    return $this->router->get($uri, $action);
}
public function getResourceUri($resource)
{
    if (! Str::contains($resource, ".")) {
        return $resource;
    }

    $segments = explode(".", $resource);

    $uri = $this->getNestedResourceUri($segments);
    // "xx/{xx}/yy/{yy}/zz"
    return str_replace("/{".$this->getResourceWildcard(end($segments))."}", "", $uri);
}
protected function getNestedResourceUri(array $segments)
{
    // ["xx","yy","zz"] => "xx/{xx}/yy/{yy}/zz/{zz}"
    return implode("/", array_map(function ($s) {
        return $s."/{".$this->getResourceWildcard($s)."}";
    }, $segments));
}
protected function getResourceAction($resource, $controller, $method, $options)
{
    $name = $this->getResourceRouteName($resource, $method, $options);

    $action = ["as" => $name, "uses" => $controller."@".$method];

    if (isset($options["middleware"])) {
        $action["middleware"] = $options["middleware"];
    }

    return $action;
}
protected function getResourceRouteName($resource, $method, $options)
{
    $name = $resource;
    
    if (isset($options["names"])) {
        if (is_string($options["names"])) {
            $name = $options["names"];
        } elseif (isset($options["names"][$method])) {
            return $options["names"][$method];
        }
    }

    $prefix = isset($options["as"]) ? $options["as"]."." : "";

    return trim(sprintf("%s%s.%s", $prefix, $name, $method), ".");
}

小結

資源類型的構造，實際上會被轉化為構造多個默認資源的路由，本質依然是基本構造