Add base functionality

composer.json

@@ -26,10 +26,26 @@
     "require-dev": {
         "doctrine/coding-standard": "^4.0",
         "infection/infection": "^0.8",
+        "middlewares/negotiation": "^1.0",
         "phpstan/phpstan": "^0.10@dev",
         "phpstan/phpstan-phpunit": "^0.10@dev",
         "phpstan/phpstan-strict-rules": "^0.10@dev",
         "phpunit/phpunit": "^7.0",
-        "squizlabs/php_codesniffer": "^3.2"
+        "squizlabs/php_codesniffer": "^3.2",
+        "zendframework/zend-diactoros": "^1.7"
+    },
+    "suggest": {
+        "middlewares/negotiation": "For acceptable format identification",
+        "zendframework/zend-diactoros": "For concrete implementation of PSR-7"
+    },
+    "autoload": {
+        "psr-4": {
+            "Lcobucci\\ContentNegotiation\\": "src"
+        }
+    },
+    "autoload-dev": {
+        "psr-4": {
+            "Lcobucci\\ContentNegotiation\\Tests\\": "tests"
+        }
     }
 }

phpcs.xml.dist

@@ -10,7 +10,9 @@
     <file>src</file>
     <file>tests</file>
 
-    <rule ref="Doctrine" />
+    <rule ref="Doctrine">
+        <exclude name="SlevomatCodingStandard.Commenting.RequireOneLinePropertyDocComment" />
+    </rule>
 
     <rule ref="SlevomatCodingStandard.TypeHints.DeclareStrictTypes">
         <properties>
@@ -25,4 +27,6 @@
             <property name="spacesCountBeforeColon" value="0"/>
         </properties>
     </rule>
+
+    <rule ref="SlevomatCodingStandard.Commenting.DisallowOneLinePropertyDocComment" />
 </ruleset>

src/ContentCouldNotBeFormatted.php

@@ -0,0 +1,10 @@
+<?php
+declare(strict_types=1);
+
+namespace Lcobucci\ContentNegotiation;
+
+use RuntimeException;
+
+final class ContentCouldNotBeFormatted extends RuntimeException
+{
+}

src/ContentTypeMiddleware.php

@@ -0,0 +1,113 @@
+<?php
+declare(strict_types=1);
+
+namespace Lcobucci\ContentNegotiation;
+
+use Fig\Http\Message\StatusCodeInterface;
+use Middlewares\ContentType;
+use Psr\Http\Message\ResponseInterface;
+use Psr\Http\Message\ServerRequestInterface;
+use Psr\Http\Message\StreamInterface;
+use Psr\Http\Server\MiddlewareInterface;
+use Psr\Http\Server\RequestHandlerInterface;
+use Zend\Diactoros\Stream;
+use function strpos;
+use function substr;
+
+final class ContentTypeMiddleware implements MiddlewareInterface
+{
+    /**
+     * @var MiddlewareInterface
+     */
+    private $negotiator;
+
+    /**
+     * @var callable
+     */
+    private $streamFactory;
+
+    /**
+     * @var Formatter[]
+     */
+    private $formatters;
+
+    /**
+     * @param Formatter[] $formatters
+     */
+    public function __construct(
+        MiddlewareInterface $negotiator,
+        array $formatters,
+        callable $streamFactory
+    ) {
+        $this->negotiator    = $negotiator;
+        $this->formatters    = $formatters;
+        $this->streamFactory = $streamFactory;
+    }
+
+    /**
+     * @param mixed[]     $formats
+     * @param Formatter[] $formatters
+     */
+    public static function fromRecommendedSettings(
+        array $formats,
+        array $formatters,
+        ?callable $streamFactory = null
+    ): self {
+        return new self(
+            new ContentType($formats),
+            $formatters,
+            function () use ($streamFactory): StreamInterface {
+                return $streamFactory !== null ? $streamFactory() : new Stream('php://temp', 'wb+');
+            }
+        );
+    }
+
+    /**
+     * {@inheritdoc}
+     *
+     * @throws ContentCouldNotBeFormatted
+     */
+    public function process(ServerRequestInterface $request, RequestHandlerInterface $handler): ResponseInterface
+    {
+        $response = $this->negotiator->process($request, $handler);
+
+        if (! $response instanceof UnformattedResponse) {
+            return $response;
+        }
+
+        $contentType = $this->extractContentType($response->getHeaderLine('Content-Type'));
+        $formatter   = $this->formatters[$contentType] ?? null;
+
+        return $this->formatResponse($response, $formatter);
+    }
+
+    private function extractContentType(string $contentType): string
+    {
+        $charsetSeparatorPosition = strpos($contentType, ';');
+
+        if ($charsetSeparatorPosition === false) {
+            return $contentType;
+        }
+
+        return substr($contentType, 0, $charsetSeparatorPosition);
+    }
+
+    /**
+     * @throws ContentCouldNotBeFormatted
+     */
+    private function formatResponse(UnformattedResponse $response, ?Formatter $formatter): ResponseInterface
+    {
+        /** @var StreamInterface $body */
+        $body     = ($this->streamFactory)();
+        $response = $response->withBody($body);
+
+        if ($formatter === null) {
+            return $response->withStatus(StatusCodeInterface::STATUS_NOT_ACCEPTABLE);
+        }
+
+        $body->write($formatter->format($response->getUnformattedContent()));
+        $body->rewind();
+
+        return $response;
+    }
+}

src/Formatter.php

@@ -0,0 +1,14 @@
+<?php
+declare(strict_types=1);
+
+namespace Lcobucci\ContentNegotiation;
+
+interface Formatter
+{
+    /**
+     * @param mixed $content
+     *
+     * @throw ContentCouldNotBeFormatted
+     */
+    public function format($content): string;
+}

src/UnformattedResponse.php

@@ -0,0 +1,167 @@
+<?php
+declare(strict_types=1);
+
+namespace Lcobucci\ContentNegotiation;
+
+use Psr\Http\Message\ResponseInterface;
+use Psr\Http\Message\StreamInterface;
+
+final class UnformattedResponse implements ResponseInterface
+{
+    /**
+     * @var ResponseInterface
+     */
+    private $decoratedResponse;
+
+    /**
+     * @var mixed
+     */
+    private $unformattedContent;
+
+    /**
+     * @param mixed $unformattedContent
+     */
+    public function __construct(ResponseInterface $decoratedResponse, $unformattedContent)
+    {
+        $this->decoratedResponse  = $decoratedResponse;
+        $this->unformattedContent = $unformattedContent;
+    }
+
+    /**
+     * @return mixed
+     */
+    public function getUnformattedContent()
+    {
+        return $this->unformattedContent;
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function getProtocolVersion()
+    {
+        return $this->decoratedResponse->getProtocolVersion();
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function withProtocolVersion($version)
+    {
+        return new self(
+            $this->decoratedResponse->withProtocolVersion($version),
+            $this->unformattedContent
+        );
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function getHeaders()
+    {
+        return $this->decoratedResponse->getHeaders();
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function hasHeader($name)
+    {
+        return $this->decoratedResponse->hasHeader($name);
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function getHeader($name)
+    {
+        return $this->decoratedResponse->getHeader($name);
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function getHeaderLine($name)
+    {
+        return $this->decoratedResponse->getHeaderLine($name);
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function withHeader($name, $value)
+    {
+        return new self(
+            $this->decoratedResponse->withHeader($name, $value),
+            $this->unformattedContent
+        );
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function withAddedHeader($name, $value)
+    {
+        return new self(
+            $this->decoratedResponse->withAddedHeader($name, $value),
+            $this->unformattedContent
+        );
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function withoutHeader($name)
+    {
+        return new self(
+            $this->decoratedResponse->withoutHeader($name),
+            $this->unformattedContent
+        );
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function getBody()
+    {
+        return $this->decoratedResponse->getBody();
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function withBody(StreamInterface $body)
+    {
+        return new self(
+            $this->decoratedResponse->withBody($body),
+            $this->unformattedContent
+        );
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function getStatusCode()
+    {
+        return $this->decoratedResponse->getStatusCode();
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function withStatus($code, $reasonPhrase = '')
+    {
+        return new self(
+            $this->decoratedResponse->withStatus($code, $reasonPhrase),
+            $this->unformattedContent
+        );
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function getReasonPhrase()
+    {
+        return $this->decoratedResponse->getReasonPhrase();
+    }
+}