From 09fd1c9f19995e04b3c4893cb9fa00aa2ce17172 Mon Sep 17 00:00:00 2001
From: Jared Hendrickson <jaredhendrickson13@gmail.com>
Date: Mon, 9 Sep 2024 15:28:59 -0600
Subject: [PATCH] feat: add BinaryContentHandler to handle
 application/octet-stream

---
 .../ContentHandlers/BinaryContentHandler.inc  |  92 ++++++++++++++++
 ...ntHandlersBinaryContentHandlerTestCase.inc | 102 ++++++++++++++++++
 2 files changed, 194 insertions(+)
 create mode 100644 pfSense-pkg-RESTAPI/files/usr/local/pkg/RESTAPI/ContentHandlers/BinaryContentHandler.inc
 create mode 100644 pfSense-pkg-RESTAPI/files/usr/local/pkg/RESTAPI/Tests/APIContentHandlersBinaryContentHandlerTestCase.inc

diff --git a/pfSense-pkg-RESTAPI/files/usr/local/pkg/RESTAPI/ContentHandlers/BinaryContentHandler.inc b/pfSense-pkg-RESTAPI/files/usr/local/pkg/RESTAPI/ContentHandlers/BinaryContentHandler.inc
new file mode 100644
index 000000000..5aaec196f
--- /dev/null
+++ b/pfSense-pkg-RESTAPI/files/usr/local/pkg/RESTAPI/ContentHandlers/BinaryContentHandler.inc
@@ -0,0 +1,92 @@
+<?php
+
+namespace RESTAPI\ContentHandlers;
+
+use RESTAPI\Core\ContentHandler;
+use RESTAPI\Core\Response;
+use RESTAPI\Responses\NotAcceptableError;
+use RESTAPI\Responses\ServerError;
+use RESTAPI\Responses\Success;
+
+/**
+ * Defines a ContentHandler for handling binary data. This is primarily used to handle file downloads.
+ * @note In context to Models, this content handler can only encode the data as a binary file for download if
+ * the model contains both a $filename containing the name of the file to download and a $binary_data containing
+ * the binary data to download.
+ */
+class BinaryContentHandler extends ContentHandler {
+    /**
+     * The MIME type associated with this content handler.
+     * @var string $mime_type
+     */
+    public string $mime_type = 'application/octet-stream';
+
+    /**
+     * The help text for encoding content with this content handler.
+     * @var string $encode_help_text
+     */
+    public string $encode_help_text = 'Downloads the response as generic binary data.';
+
+    /**
+     * Encodes/preps the given content as a binary file for download.
+     * @param mixed|null $content The content to encode.
+     * @param Response|null $context The Response object that contains the content to encode.
+     * @return mixed The encoded content.
+     */
+    protected function _encode(mixed $content = null, ?Response $context = null): mixed {
+        # We cannot encode error messages. If an error, rethrow it to be handled by the default Response handler
+        if (!$context instanceof Success) {
+            throw $context;
+        }
+
+        # Extract the content's data array
+        $content = $content['data'];
+
+        # Ensure te content provided can even be encoded as a binary file
+        if (!is_array($content) or !$content['binary_data'] or !$content['filename']) {
+            throw new NotAcceptableError(
+                message: 'The requested resource cannot be encoded as a binary file.',
+                response_id: 'BINARY_CONTENT_HANDLER_RESOURCE_NOT_SUPPORTED',
+            );
+        }
+
+        # Ensure the filename is actually a filename
+        if (!preg_match('/^[a-zA-Z0-9_\-.]+$/', $content['filename'])) {
+            throw new ServerError(
+                message: "The requested filename for this resource is invalid.",
+                response_id: 'BINARY_CONTENT_HANDLER_INVALID_FILENAME',
+            );
+        }
+
+        # Ensure the data is actually binary data
+        if (mb_detect_encoding($content['binary_data'], 'UTF-8', true) !== false) {
+            throw new ServerError(
+                message: "The requested data does not appear to be binary data.",
+                response_id: 'BINARY_CONTENT_HANDLER_INVALID_DATA',
+            );
+        }
+
+        header('Content-Description: File Transfer');
+        header('Content-Disposition: attachment; filename="' . $content['filename'] . '"');
+        header('Cache-Control: must-revalidate');
+        header('Pragma: public');
+        header('Expires: 0');
+        return $content['binary_data'];
+    }
+
+    /**
+     * @inheritDoc
+     */
+    public function to_openapi_schema(Response $response): array
+    {
+        return [
+            $this->mime_type => [
+                'description' => $this->encode_help_text,
+                'schema' => [
+                    'type' => 'string',
+                    'format' => 'binary',
+                ],
+            ],
+        ];
+    }
+}
diff --git a/pfSense-pkg-RESTAPI/files/usr/local/pkg/RESTAPI/Tests/APIContentHandlersBinaryContentHandlerTestCase.inc b/pfSense-pkg-RESTAPI/files/usr/local/pkg/RESTAPI/Tests/APIContentHandlersBinaryContentHandlerTestCase.inc
new file mode 100644
index 000000000..a5573f839
--- /dev/null
+++ b/pfSense-pkg-RESTAPI/files/usr/local/pkg/RESTAPI/Tests/APIContentHandlersBinaryContentHandlerTestCase.inc
@@ -0,0 +1,102 @@
+<?php
+
+namespace RESTAPI\Tests;
+
+use RESTAPI\ContentHandlers\BinaryContentHandler;
+use RESTAPI\Core\TestCase;
+use RESTAPI\Responses\Success;
+
+class APIContentHandlersBinaryContentHandlerTestCase extends TestCase
+{
+    /**
+     * Ensure the encode() method throws an error if the required 'binary_data' and 'filename' keys are not present in
+     * the content array.
+     */
+    public function test_encode_requires_binary_data_and_filename_keys(): void
+    {
+        $this->assert_throws_response(
+            response_id: 'BINARY_CONTENT_HANDLER_RESOURCE_NOT_SUPPORTED',
+            code: 406,
+            callable: function () {
+                $handler = new BinaryContentHandler();
+                $response = new Success(message: '', response_id: ''); # Required as context for the encode() method
+                $handler->encode(['data' => []], $response);
+            }
+        );
+    }
+
+    /**
+     * Ensure the encode() method throws an error if the 'filename' key contains invalid characters.
+     */
+    public function test_encode_requires_valid_filename(): void
+    {
+        $this->assert_throws_response(
+            response_id: 'BINARY_CONTENT_HANDLER_INVALID_FILENAME',
+            code: 500,
+            callable: function () {
+                $handler = new BinaryContentHandler();
+                $response = new Success(message: '', response_id: ''); # Required as context for the encode() method
+                $handler->encode(['data' => ['binary_data' => 'data', 'filename' => 'invalid file name']], $response);
+            }
+        );
+    }
+
+    /**
+     * Ensure the encode() method does not throw an error if the required 'binary_data' and 'filename' keys are present in
+     * the content array.
+     */
+    public function test_encode_requires_binary_data(): void {
+        $this->assert_throws_response(
+            response_id: 'BINARY_CONTENT_HANDLER_INVALID_DATA',
+            code: 500,
+            callable: function () {
+                $handler = new BinaryContentHandler();
+                $response = new Success(message: '', response_id: ''); # Required as context for the encode() method
+                $handler->encode(
+                    ['data' => ['binary_data' => 'data', 'filename' => 'valid_file_name.txt']],
+                    $response
+                );
+            }
+        );
+    }
+
+    /**
+     * Ensures the encode() method correctly encodes the content as a binary file for download.
+     */
+    public function test_encode(): void
+    {
+        $this->assert_does_not_throw(
+            callable: function () {
+                $response = new Success(message: '', response_id: '');
+                $handler = new BinaryContentHandler();
+                $binary_data = random_bytes(16);
+                $handler->encode(
+                    ['data' => ['binary_data' => $binary_data, 'filename' => 'valid_file_name.txt']],
+                    $response
+                );
+            }
+        );
+    }
+
+    /**
+     * Ensures the to_openapi_schema() method returns the correct schema for the BinaryContentHandler.
+     */
+    public function test_to_openapi_schema(): void
+    {
+        $handler = new BinaryContentHandler();
+        $response = new Success(message: '', response_id: ''); # Required as context for the to_openapi_schema() method
+        $this->assert_equals(
+            $handler->to_openapi_schema($response),
+            [
+                $handler->mime_type => [
+                    'description' => $handler->encode_help_text,
+                    'schema' => [
+                        'type' => 'string',
+                        'format' => 'binary',
+                    ],
+                ],
+            ]
+        );
+    }
+
+}
\ No newline at end of file