Merge pull request #233 from llvdl/gh-195

gh-195 added example slim application to handle file uploads

docs/cookbook/uploading-files.md

@@ -44,3 +44,87 @@ Below is an example HTML form that contains both single and multiple file upload
 {% endhighlight %}
 <figcaption>Figure 1: Example HTML form for file uploads</figcaption>
 </figure>
+
+Uploaded files can be moved to a directory using the `moveTo` method. Below is an example application
+that handles the uploaded files of the HTML form above.
+
+<figure>
+{% highlight php %}
+<?php
+
+require_once __DIR__ . '/vendor/autoload.php';
+
+use Slim\Http\Request;
+use Slim\Http\Response;
+use Slim\Http\UploadedFile;
+
+$app = new \Slim\App();
+
+$container = $app->getContainer();
+$container['upload_directory'] = __DIR__ . '/uploads';
+
+$app->post('/', function(Request $request, Response $response) {
+    $directory = $this->get('upload_directory');
+
+    $uploadedFiles = $request->getUploadedFiles();
+
+    // handle single input with single file upload
+    $uploadedFile = $uploadedFiles['example1'];
+    if ($uploadedFile->getError() === UPLOAD_ERR_OK) {
+        $filename = moveUploadedFile($directory, $uploadedFile);
+        $response->write('uploaded ' . $filename . '<br/>');
+    }
+
+
+    // handle multiple inputs with the same key
+    foreach ($uploadedFiles['example2'] as $uploadedFile) {
+        if ($uploadedFile->getError() === UPLOAD_ERR_OK) {
+            $filename = moveUploadedFile($directory, $uploadedFile);
+            $response->write('uploaded ' . $filename . '<br/>');
+        }
+    }
+
+    // handle single input with multiple file uploads
+    foreach ($uploadedFiles['example3'] as $uploadedFile) {
+        if ($uploadedFile->getError() === UPLOAD_ERR_OK) {
+            $filename = moveUploadedFile($directory, $uploadedFile);
+            $response->write('uploaded ' . $filename . '<br/>');
+        }
+    }
+
+    // handle single input with multiple file uploads
+    foreach ($uploadedFiles['example3'] as $uploadedFile) {
+        if ($uploadedFile->getError() === UPLOAD_ERR_OK) {
+            $filename = moveUploadedFile($directory, $uploadedFile);
+            $response->write('uploaded ' . $filename . '<br/>');
+        }
+    }
+});
+
+/**
+ * Moves the uploaded file to the upload directory and assigns it a unique name
+ * to avoid overwriting an existing uploaded file.
+ *
+ * @param string $directory directory to which the file is moved
+ * @param UploadedFile $uploaded file uploaded file to move
+ * @return string filename of moved file
+ */
+function moveUploadedFile($directory, UploadedFile $uploadedFile)
+{
+    $extension = pathinfo($uploadedFile->getClientFilename(), PATHINFO_EXTENSION);
+    $basename = bin2hex(random_bytes(8)); // see http://php.net/manual/en/function.random-bytes.php
+    $filename = sprintf('%s.%0.8s', $basename, $extension);
+
+    $uploadedFile->moveTo($directory . DIRECTORY_SEPARATOR . $filename);
+
+    return $filename;
+}
+
+$app->run();
+{% endhighlight %}
+<figcaption>Figure 2: Example Slim applcation to handle the uploaded files</figcaption>
+</figure>
+
+See also
+--------
+* [https://akrabat.com/psr-7-file-uploads-in-slim-3/](https://akrabat.com/psr-7-file-uploads-in-slim-3/)