First implementation

Author: snapshotpl

.gitignore

@@ -0,0 +1,2 @@
+/vendor/
+composer.lock

.travis.yml

@@ -0,0 +1,18 @@
+language: php
+
+php:
+  - 5.6
+  - 7.0
+  - 7.1
+  - hhvm
+
+env:
+  - DEPS=lowest
+  - DEPS=latest
+
+before_script:
+  - if [[ $DEPS == 'lowest' ]]; then travis_retry composer update --prefer-stable --no-interaction --prefer-lowest ; fi
+  - if [[ $DEPS == 'latest' ]]; then travis_retry composer update --prefer-stable --no-interaction ; fi
+
+script:
+  - ./vendor/bin/phpunit

composer.json

@@ -0,0 +1,29 @@
+{
+    "name": "php-middleware/double-pass-compatibility",
+    "description": "Tools for support double pass middewares in PSR-15",
+    "type": "library",
+    "keywords": [
+        "middleware",
+        "psr",
+        "psr-7",
+        "psr-15"
+    ],
+    "require": {
+        "php": ">=5.6",
+        "psr/http-message": "^1.0",
+        "http-interop/http-middleware": "^0.4.1"
+    },
+    "require-dev": {
+        "phpunit/phpunit": "^5.6 || ^6.1"
+    },
+    "autoload": {
+        "psr-4": {
+            "PhpMiddleware\\": "src/"
+        }
+    },
+    "autoload-dev": {
+        "psr-4": {
+            "PhpMiddlewareTest\\": "test/"
+        }
+    }
+}

phpunit.xml

@@ -0,0 +1,15 @@
+<?xml version="1.0" encoding="UTF-8"?>
+
+<phpunit bootstrap="./vendor/autoload.php" colors="true">
+    <testsuites>
+        <testsuite>
+            <directory>./test</directory>
+        </testsuite>
+    </testsuites>
+
+    <filter>
+        <whitelist processUncoveredFilesFromWhitelist="true">
+            <directory suffix=".php">./src</directory>
+        </whitelist>
+    </filter>
+</phpunit>

src/AbstractDoublePassCompatibilityMiddleware.php

@@ -0,0 +1,10 @@
+<?php
+
+namespace PhpMiddleware;
+
+use Interop\Http\ServerMiddleware\MiddlewareInterface;
+
+abstract class AbstractDoublePassCompatibilityMiddleware implements MiddlewareInterface
+{
+    use DoublePassCompatibilityTrait;
+}

src/DoublePassCompatibilityTrait.php

@@ -0,0 +1,23 @@
+<?php
+
+namespace PhpMiddleware;
+
+use Psr\Http\Message\ResponseInterface;
+use Psr\Http\Message\ServerRequestInterface;
+
+trait DoublePassCompatibilityTrait
+{
+    /**
+     * @param ServerRequestInterface $request
+     * @param ResponseInterface $response
+     * @param callable $next
+     *
+     * @return ResponseInterface
+     */
+    final public function __invoke(ServerRequestInterface $request, ResponseInterface $response, callable $next)
+    {
+        $delegate = new DoublePassDelegate($next, $response);
+
+        return $this->process($request, $delegate);
+    }
+}

src/DoublePassDelegate.php

@@ -0,0 +1,24 @@
+<?php
+
+namespace PhpMiddleware;
+
+use Interop\Http\ServerMiddleware\DelegateInterface;
+use Psr\Http\Message\ResponseInterface;
+use Psr\Http\Message\ServerRequestInterface;
+
+final class DoublePassDelegate implements DelegateInterface
+{
+    private $delegate;
+    private $response;
+
+    public function __construct(callable $delegate, ResponseInterface $response)
+    {
+        $this->delegate = $delegate;
+        $this->response = $response;
+    }
+
+    public function process(ServerRequestInterface $request)
+    {
+        return call_user_func($this->delegate, $request, $this->response);
+    }
+}

test/AbstractDoublePassCompatibilityMiddlewareTest.php

@@ -0,0 +1,51 @@
+<?php
+
+namespace PhpMiddleware\Test;
+
+use Interop\Http\ServerMiddleware\DelegateInterface;
+use PhpMiddleware\AbstractDoublePassCompatibilityMiddleware;
+use PHPUnit\Framework\TestCase;
+use Psr\Http\Message\ResponseInterface;
+use Psr\Http\Message\ServerRequestInterface;
+
+class AbstractDoublePassCompatibilityMiddlewareTest extends TestCase
+{
+    public function testExecuteSinglePassOnDoublePassCall()
+    {
+        $request = $this->getMockBuilder(ServerRequestInterface::class)->getMock();
+        $response = $this->getMockBuilder(ResponseInterface::class)->getMock();
+
+        $next = function ($request, $response) {
+            return $response;
+        };
+
+        $middleware = $this->getMockForAbstractClass(AbstractDoublePassCompatibilityMiddleware::class);
+        $middleware->method('process')->willReturnCallback(function(ServerRequestInterface $request, DelegateInterface $delegate) {
+            return $delegate->process($request);
+        });
+
+        $result = $middleware($request, $response, $next);
+
+        $this->assertSame($response, $result);
+    }
+
+    public function testExecuteSinglePassOnDoublePassCallAndReturnNewResponse()
+    {
+        $request = $this->getMockBuilder(ServerRequestInterface::class)->getMock();
+        $response = $this->getMockBuilder(ResponseInterface::class)->getMock();
+        $newResponse = $this->getMockBuilder(ResponseInterface::class)->getMock();
+
+        $next = function ($request, $response) {
+            return $response;
+        };
+
+        $middleware = $this->getMockForAbstractClass(AbstractDoublePassCompatibilityMiddleware::class);
+        $middleware->method('process')->willReturnCallback(function(ServerRequestInterface $request, DelegateInterface $delegate) use ($newResponse) {
+            return $newResponse;
+        });
+
+        $result = $middleware($request, $response, $next);
+
+        $this->assertSame($newResponse, $result);
+    }
+}