Added fallback on common classes. Puli is now optional

spec/ClassDiscoverySpec.php

@@ -47,7 +47,7 @@ function it_throws_an_exception_when_binding_not_found(Discovery $discovery)
     {
         $discovery->findBindings('InvalidBinding')->willReturn([]);
 
-        $this->shouldThrow('Http\Discovery\NotFoundException')->duringFindOneByType('InvalidBinding');
+        $this->shouldThrow('Http\Discovery\Exception\NotFoundException')->duringFindOneByType('InvalidBinding');
     }
 
     function it_returns_a_class_binding(Discovery $discovery, ClassBinding $binding)

src/ClassDiscovery.php

@@ -2,6 +2,11 @@
 
 namespace Http\Discovery;
 
+use Http\Discovery\Exception\NotFoundException;
+use Http\Discovery\Exception\PuliNotAvailableException;
+use Http\Discovery\FallbackStrategy\HttpClients;
+use Http\Discovery\FallbackStrategy\DiactorosFactory;
+use Http\Discovery\FallbackStrategy\GuzzleFactory;
 use Puli\Discovery\Api\Discovery;
 
 /**
@@ -29,13 +34,13 @@ public static function getPuliFactory()
     {
         if (null === self::$puliFactory) {
             if (!defined('PULI_FACTORY_CLASS')) {
-                throw new \RuntimeException('Puli Factory is not available');
+                throw new PuliNotAvailableException('Puli Factory is not available');
             }
 
             $puliFactoryClass = PULI_FACTORY_CLASS;
 
             if (!class_exists($puliFactoryClass)) {
-                throw new \RuntimeException('Puli Factory class does not exist');
+                throw new PuliNotAvailableException('Puli Factory class does not exist');
             }
 
             self::$puliFactory = new $puliFactoryClass();
@@ -95,6 +100,32 @@ public static function getPuliDiscovery()
      * @throws NotFoundException
      */
     public static function findOneByType($type)
+    {
+        try {
+            return self::puliFindOneByType($type);
+        } catch (PuliNotAvailableException $e) {
+            if (false !== $class = HttpClients::findOneByType($type)) {
+                return $class;
+            } elseif (false !== $class = GuzzleFactory::findOneByType($type)) {
+                return $class;
+            } elseif (false !== $class = DiactorosFactory::findOneByType($type)) {
+                return $class;
+            }
+            throw new NotFoundException('Could not find resource using Puli nor common Guzzle/Diactoros classes', 0, $e);
+        }
+    }
+
+    /**
+     * Finds a class using Puli.
+     *
+     * @param $type
+     *
+     * @return string
+     *
+     * @throws NotFoundException
+     * @throws PuliNotAvailableException
+     */
+    private static function puliFindOneByType($type)
     {
         $bindings = self::getPuliDiscovery()->findBindings($type);
 

src/NotFoundException.php → src/Exception/NotFoundException.php

@@ -1,6 +1,6 @@
 <?php
 
-namespace Http\Discovery;
+namespace Http\Discovery\Exception;
 
 /**
  * Thrown when a discovery does not find any matches.

src/Exception/PuliNotAvailableException.php

@@ -0,0 +1,12 @@
+<?php
+
+namespace Http\Discovery\Exception;
+
+/**
+ * Thrown when we can't use Puli for discovery.
+ *
+ * @author Tobias Nyholm <[email protected]>
+ */
+class PuliNotAvailableException extends \RuntimeException
+{
+}

src/FallbackStrategy/DiactorosFactory.php

@@ -0,0 +1,41 @@
+<?php
+
+namespace Http\Discovery\FallbackStrategy;
+
+/**
+ * Find Diactoros factories.
+ *
+ * @author Tobias Nyholm <[email protected]>
+ */
+class DiactorosFactory implements FallbackStrategy
+{
+    /**
+     * {@inheritdoc}
+     */
+    public static function findOneByType($type)
+    {
+        if (!class_exists('Zend\Diactoros\Request')) {
+            return false;
+        }
+
+        switch ($type) {
+            case 'Http\Message\MessageFactory':
+                if (class_exists('Http\Message\MessageFactory\DiactorosMessageFactory')) {
+                    return 'Http\Message\MessageFactory\DiactorosMessageFactory';
+                }
+                break;
+            case 'Http\Message\StreamFactory':
+                if (class_exists('Http\Message\StreamFactory\DiactorosStreamFactory')) {
+                    return 'Http\Message\StreamFactory\DiactorosStreamFactory';
+                }
+                break;
+            case 'Http\Message\UriFactory':
+                if (class_exists('Http\Message\UriFactory\DiactorosUriFactory')) {
+                    return 'Http\Message\UriFactory\DiactorosUriFactory';
+                }
+                break;
+        }
+
+        return false;
+    }
+}

src/FallbackStrategy/FallbackStrategy.php

@@ -0,0 +1,16 @@
+<?php
+
+namespace Http\Discovery\FallbackStrategy;
+
+/**
+ * @author Tobias Nyholm <[email protected]>
+ */
+interface FallbackStrategy
+{
+    /**
+     * @param $type
+     *
+     * @return string|bool class name of boolean false
+     */
+    public static function findOneByType($type);
+}

src/FallbackStrategy/GuzzleFactory.php

@@ -0,0 +1,41 @@
+<?php
+
+namespace Http\Discovery\FallbackStrategy;
+
+/**
+ * Find Guzzle factories.
+ *
+ * @author Tobias Nyholm <[email protected]>
+ */
+class GuzzleFactory implements FallbackStrategy
+{
+    /**
+     * {@inheritdoc}
+     */
+    public static function findOneByType($type)
+    {
+        if (!class_exists('GuzzleHttp\Psr7\Request')) {
+            return false;
+        }
+
+        switch ($type) {
+            case 'Http\Message\MessageFactory':
+                if (class_exists('Http\Message\MessageFactory\GuzzleMessageFactory')) {
+                    return 'Http\Message\MessageFactory\GuzzleMessageFactory';
+                }
+                break;
+            case 'Http\Message\StreamFactory':
+                if (class_exists('Http\Message\StreamFactory\GuzzleStreamFactory')) {
+                    return 'Http\Message\StreamFactory\GuzzleStreamFactory';
+                }
+                break;
+            case 'Http\Message\UriFactory':
+                if (class_exists('Http\Message\UriFactory\GuzzleUriFactory')) {
+                    return 'Http\Message\UriFactory\GuzzleUriFactory';
+                }
+                break;
+        }
+
+        return false;
+    }
+}

src/FallbackStrategy/HttpClients.php

@@ -0,0 +1,38 @@
+<?php
+
+namespace Http\Discovery\FallbackStrategy;
+
+/**
+ * Find common HTTP clients.
+ *
+ * @author Tobias Nyholm <[email protected]>
+ */
+class HttpClients implements FallbackStrategy
+{
+    /**
+     * {@inheritdoc}
+     */
+    public static function findOneByType($type)
+    {
+        switch ($type) {
+            case 'Http\Client\HttpAsyncClient':
+                $clients = ['Http\Adapter\Guzzle6\Client'];
+                foreach ($clients as $class) {
+                    if (class_exists($class)) {
+                        return $class;
+                    }
+                }
+                break;
+            case 'Http\Client\HttpClient':
+                $clients = ['Http\Adapter\Guzzle6\Client', 'Http\Adapter\Guzzle5\Client'];
+                foreach ($clients as $class) {
+                    if (class_exists($class)) {
+                        return $class;
+                    }
+                }
+                break;
+        }
+
+        return false;
+    }
+}

src/MessageFactoryDiscovery.php

@@ -2,6 +2,7 @@
 
 namespace Http\Discovery;
 
+use Http\Discovery\Exception\NotFoundException;
 use Http\Message\MessageFactory;
 
 /**

src/StreamFactoryDiscovery.php

@@ -2,6 +2,7 @@
 
 namespace Http\Discovery;
 
+use Http\Discovery\Exception\NotFoundException;
 use Http\Message\StreamFactory;
 
 /**

src/UriFactoryDiscovery.php

@@ -2,6 +2,7 @@
 
 namespace Http\Discovery;
 
+use Http\Discovery\Exception\NotFoundException;
 use Http\Message\UriFactory;
 
 /**