Create a central class for parsing of AJAX parameters in POST/PUT

CHANGELOG.md

@@ -5,6 +5,8 @@
   [#512](https://github.com./nextcloud/cookbook/pull/512/) @seyfeb
 - Speed up index of recipes by using computed properties
   [#513](https://github.com./nextcloud/cookbook/pull/513) @christianlupus
+- Central parsing of parameters for POST/PUT requests to simplify development
+  [#518](https://github.com./nextcloud/cookbook/pull/518) @christianlupus
 
 ### Fixed
 - Fixed keywords of shared recipes counted multiple times, fixes #491

lib/Controller/ConfigController.php

@@ -10,6 +10,7 @@
 use OCA\Cookbook\Service\RecipeService;
 use OCP\IURLGenerator;
 use OCA\Cookbook\Service\DbCacheService;
+use OCA\Cookbook\Helper\RestParameterParser;
 
 class ConfigController extends Controller {
 	/**
@@ -25,13 +26,19 @@ class ConfigController extends Controller {
 	 * @var DbCacheService
 	 */
 	private $dbCacheService;
+
+	/**
+	 * @var RestParameterParser
+	 */
+	private $restParser;
 
-	public function __construct($AppName, IRequest $request, IURLGenerator $urlGenerator, RecipeService $recipeService, DbCacheService $dbCacheService) {
+	public function __construct($AppName, IRequest $request, IURLGenerator $urlGenerator, RecipeService $recipeService, DbCacheService $dbCacheService, RestParameterParser $restParser) {
 		parent::__construct($AppName, $request);
 
 		$this->service = $recipeService;
 		$this->urlGenerator = $urlGenerator;
 		$this->dbCacheService = $dbCacheService;
+		$this->restParser = $restParser;
 	}
 
 	/**
@@ -55,17 +62,19 @@ public function list() {
 	public function config() {
 		$this->dbCacheService->triggerCheck();
 
-		if (isset($_POST['folder'])) {
-			$this->service->setUserFolderPath($_POST['folder']);
+		$data = $this->restParser->getParameters();
+
+		if (isset($data['folder'])) {
+			$this->service->setUserFolderPath($data['folder']);
 			$this->dbCacheService->updateCache();
 		}
 
-		if (isset($_POST['update_interval'])) {
-			$this->service->setSearchIndexUpdateInterval($_POST['update_interval']);
+		if (isset($data['update_interval'])) {
+			$this->service->setSearchIndexUpdateInterval($data['update_interval']);
 		}
 
-		if (isset($_POST['print_image'])) {
-			$this->service->setPrintImage((bool)$_POST['print_image']);
+		if (isset($data['print_image'])) {
+			$this->service->setPrintImage((bool)$data['print_image']);
 		}
 
 		return new DataResponse('OK', Http::STATUS_OK);

lib/Controller/MainController.php

@@ -10,6 +10,7 @@
 use OCP\AppFramework\Controller;
 use OCA\Cookbook\Service\RecipeService;
 use OCA\Cookbook\Service\DbCacheService;
+use OCA\Cookbook\Helper\RestParameterParser;
 
 class MainController extends Controller {
 	protected $appName;
@@ -26,14 +27,20 @@ class MainController extends Controller {
 	 * @var IURLGenerator
 	 */
 	private $urlGenerator;
+
+	/**
+	 * @var RestParameterParser
+	 */
+	private $restParser;
 
-	public function __construct(string $AppName, IRequest $request, RecipeService $recipeService, DbCacheService $dbCacheService, IURLGenerator $urlGenerator) {
+	public function __construct(string $AppName, IRequest $request, RecipeService $recipeService, DbCacheService $dbCacheService, IURLGenerator $urlGenerator, RestParameterParser $restParser) {
 		parent::__construct($AppName, $request);
 
 		$this->service = $recipeService;
 		$this->urlGenerator = $urlGenerator;
 		$this->appName = $AppName;
 		$this->dbCacheService = $dbCacheService;
+		$this->restParser = $restParser;
 	}
 
 	/**
@@ -300,12 +307,14 @@ public function create() {
 	public function import() {
 		$this->dbCacheService->triggerCheck();
 
-		if (!isset($_POST['url'])) {
+		$data = $this->restParser->getParameters();
+
+		if (!isset($data['url'])) {
 			return new DataResponse('Field "url" is required', 400);
 		}
 
 		try {
-			$recipe_file = $this->service->downloadRecipe($_POST['url']);
+			$recipe_file = $this->service->downloadRecipe($data['url']);
 			$recipe_json = $this->service->parseRecipeFile($recipe_file);
 			$this->dbCacheService->addRecipe($recipe_file);
 
@@ -323,7 +332,7 @@ public function new() {
 		$this->dbCacheService->triggerCheck();
 
 		try {
-			$recipe_data = $_POST;
+			$recipe_data = $this->restParser->getParameters();
 			$file = $this->service->addRecipe($recipe_data);
 			$this->dbCacheService->addRecipe($file);
 
@@ -370,9 +379,7 @@ public function update($id) {
 		$this->dbCacheService->triggerCheck();
 
 		try {
-			$recipe_data = [];
-
-			parse_str(file_get_contents("php://input"), $recipe_data);
+			$recipe_data = $this->restParser->getParameters();
 
 			$recipe_data['id'] = $id;
 

lib/Controller/RecipeController.php

@@ -12,6 +12,7 @@
 use OCA\Cookbook\Service\RecipeService;
 use OCP\IURLGenerator;
 use OCA\Cookbook\Service\DbCacheService;
+use OCA\Cookbook\Helper\RestParameterParser;
 
 class RecipeController extends Controller {
 	/**
@@ -27,13 +28,19 @@ class RecipeController extends Controller {
 	 * @var DbCacheService
 	 */
 	private $dbCacheService;
+
+	/**
+	 * @var RestParameterParser
+	 */
+	private $restParser;
 
-	public function __construct($AppName, IRequest $request, IURLGenerator $urlGenerator, RecipeService $recipeService, DbCacheService $dbCacheService) {
+	public function __construct($AppName, IRequest $request, IURLGenerator $urlGenerator, RecipeService $recipeService, DbCacheService $dbCacheService, RestParameterParser $restParser) {
 		parent::__construct($AppName, $request);
 
 		$this->service = $recipeService;
 		$this->urlGenerator = $urlGenerator;
 		$this->dbCacheService = $dbCacheService;
+		$this->restParser = $restParser;
 	}
 
 	/**
@@ -89,8 +96,7 @@ public function show($id) {
 	public function update($id) {
 		$this->dbCacheService->triggerCheck();
 
-		$recipeData = [];
-		parse_str(file_get_contents("php://input"), $recipeData);
+		$recipeData = $this->restParser->getParameters();
 		$file = $this->service->addRecipe($recipeData);
 		$this->dbCacheService->addRecipe($file);
 
@@ -110,7 +116,7 @@ public function update($id) {
 	public function create() {
 		$this->dbCacheService->triggerCheck();
 
-		$recipeData = $_POST;
+		$recipeData = $this->restParser->getParameters();
 		$file = $this->service->addRecipe($recipeData);
 		$this->dbCacheService->addRecipe($file);
 

lib/Helper/RestParameterParser.php

@@ -0,0 +1,149 @@
+<?php
+
+namespace OCA\Cookbook\Helper;
+
+use function GuzzleHttp\json_decode;
+use OCP\IL10N;
+
+class RestParameterParser {
+	private const CHARSET = 'charset';
+	private const CONTENT_TYPE = 'CONTENT_TYPE';
+	private const REQUEST_METHOD = 'REQUEST_METHOD';
+
+	/**
+	 * @var IL10N
+	 */
+	private $l;
+
+	public function __construct(IL10N $l10n) {
+		$this->l = $l10n;
+	}
+
+	/**
+	 * Fetch the parameters from the input accordingly
+	 *
+	 * Depending on the way of transmitting parameters from the browser to the PHP script different ways to recover these have to be done.
+	 * This is a helper that should cover this.
+	 *
+	 * @return array The parameters transmitted
+	 */
+	public function getParameters(): array {
+		if (isset($_SERVER[self::CONTENT_TYPE])) {
+			$parts = explode(';', $_SERVER[self::CONTENT_TYPE], 2);
+
+			switch (trim($parts[0])) {
+				case 'application/json':
+					$enc = $this->getEncoding($_SERVER[self::CONTENT_TYPE]);
+					return $this->parseApplicationJSON($enc);
+					break;
+
+				case 'multipart/form-data':
+					if ($this->isPost()) {
+						return $_POST;
+					} else {
+						throw new \Exception($this->l->t('Cannot parse non-POST multipart encoding. This is a bug.'));
+					}
+					break;
+
+				case 'application/x-www-form-urlencoded':
+					if ($this->isPost()) {
+						return $_POST;
+					} else {
+						$enc = $this->getEncoding($_SERVER[self::CONTENT_TYPE]);
+						return $this->parseUrlEncoded($enc);
+					}
+					break;
+			}
+		} else {
+			throw new \Exception($this->l->t('Cannot detect type of transmitted data. This is a bug, please report it.'));
+		}
+	}
+
+	/**
+	 * Parse data transmitted as application/json
+	 * @param $encoding string The encoding to use
+	 * @return array
+	 */
+	private function parseApplicationJSON(string $encoding): array {
+		$rawData = file_get_contents('php://input');
+
+		if ($encoding !== 'UTF-8') {
+			$rawData = iconv($encoding, 'UTF-8', $rawData);
+		}
+		return json_decode($rawData, true);
+	}
+
+	/**
+	 * Parse the URL encoded value transmitted
+	 *
+	 * This is by far no ideal solution but just a quick hack in order to cope with this situation.
+	 * Either use the POST method (where PHP does the parsing) or use application/json
+	 *
+	 * @param string $encoding The encoding to use
+	 * @throws \Exception If the requested string is not well-formatted accoring to the minimal implementation
+	 * @return array The values transmitted
+	 */
+	private function parseUrlEncoded(string $encoding): array {
+		$rawData = file_get_contents('php://input');
+		if ($encoding !== 'UTF-8') {
+			$rawData = iconv($encoding, 'UTF-8', $rawData);
+		}
+
+		$ret = [];
+		foreach (explode('&', $rawData) as $assignment) {
+			$parts = explode('=', $assignment, 2);
+
+			if (count($parts) < 2) {
+				throw new \Exception($this->l->t('Invlaid URL-encoded string found. Please report a bug.'));
+			}
+
+			$key = $parts[0];
+			$value = urldecode($parts[1]);
+
+			if (str_ends_with($key, '[]')) {
+				// Drop '[]' at the end
+				$key = substr($key, 0, -2);
+
+				if (!array_key_exists($key, $ret)) {
+					$ret[$key] = [];
+				}
+
+				$ret[$key][] = $value;
+			} else {
+				$ret[$key] = $value;
+			}
+		}
+
+		return $ret;
+	}
+
+	/**
+	 * Get the encoding from the header
+	 * @param string $header The header to parse
+	 * @return string The encoding as string
+	 */
+	private function getEncoding(string $header): string {
+		$parts = explode(';', $header);
+
+		// Fallback encoding
+		$enc = 'UTF-8';
+
+		for ($i = 1; $i < count($parts); $i++) {
+			if (str_starts_with(trim($parts[$i]), self::CHARSET)) {
+				// Drop string 'charset='
+				$enc = substr(trim($parts[1]), strlen(self::CHARSET) + 1);
+				break;
+			}
+		}
+
+		return $enc;
+	}
+
+	/**
+	 * Check if the request is a POST request
+	 * @return bool true, if the request is a POST request.
+	 */
+	private function isPost(): bool {
+		return $_SERVER[self::REQUEST_METHOD] === 'POST';
+	}
+}