createSession method implementation for W3C client

Author: itnelo

README.md

@@ -35,8 +35,8 @@ See a self-documented [ClientInterface.php](src/ClientInterface.php) for the API
 ## See also
 
 - [php-webdriver/webdriver](https://github.com/php-webdriver/php-webdriver) — the original, "blocking" implementation; 
-to get information how to use some advanced methods, for example, [WebDriverKeys](https://github.com/php-webdriver/php-webdriver/blob/main/lib/WebDriverKeys.php#L10)
-helper describes Unicode strings for sending special inputs to page elements (e.g. `Ctrl`, `Alt`, etc.).
+to get information how to use some advanced methods. For example, [WebDriverKeys](https://github.com/php-webdriver/php-webdriver/blob/main/lib/WebDriverKeys.php#L10)
+helper describes Unicode strings for sending special inputs to page elements (e.g. `Ctrl`, `Alt` and other keys).
 
 ## Changelog
 

composer.json

@@ -25,6 +25,7 @@
         "php": ">=7.4",
         "react/http": "^1.1",
         "react/promise": "^2.8",
+        "react/promise-timer": "^1.6",
         "symfony/options-resolver": "^5.1"
     },
     "require-dev": {

src/Client/W3CClient.php

@@ -16,10 +16,14 @@
 namespace Itnelo\React\WebDriver\Client;
 
 use Itnelo\React\WebDriver\ClientInterface;
+use Psr\Http\Message\ResponseInterface;
 use React\Http\Browser;
+use React\Promise\Deferred;
 use React\Promise\PromiseInterface;
+use RuntimeException;
 use Symfony\Component\OptionsResolver\Exception\ExceptionInterface as OptionsResolverExceptionInterface;
 use Symfony\Component\OptionsResolver\OptionsResolver;
+use Throwable;
 
 /**
  * W3C compliant WebDriver client for Selenium Grid server (hub) that performs asynchronously.
@@ -129,15 +133,66 @@ function (OptionsResolver $requestOptionsResolver) {
      */
     public function getSessionIdentifiers(): PromiseInterface
     {
-        // TODO: Implement getSessionIdentifiers() method.
+        // todo
     }
 
     /**
      * {@inheritDoc}
      */
     public function createSession(): PromiseInterface
     {
-        // TODO: Implement createSession() method.
+        $sessionOpeningDeferred = new Deferred();
+
+        $requestUri = sprintf(
+            'http://%s:%d/wd/hub/session',
+            $this->_options['server']['host'],
+            $this->_options['server']['port']
+        );
+
+        $requestHeaders = [
+            'Content-Type' => 'application/json; charset=UTF-8',
+        ];
+
+        // todo: implement custom executable args / prefs support (omitted in the interface)
+        $requestContents = '{"capabilities":{"firstMatch":[{"browserName":"chrome","goog:chromeOptions":{"prefs":{"intl.accept_languages":"RU-ru,ru,en-US,en"},"args":["--user-data-dir=\/opt\/google\/chrome\/profiles"]}}]},"desiredCapabilities":{"browserName":"chrome","platform":"ANY","goog:chromeOptions":{"prefs":{"intl.accept_languages":"RU-ru,ru,en-US,en"},"args":["--user-data-dir=\/opt\/google\/chrome\/profiles"]}}}';
+
+        $responsePromise = $this->httpClient->post($requestUri, $requestHeaders, $requestContents);
+
+        $responsePromise->then(
+            function (ResponseInterface $response) use ($sessionOpeningDeferred) {
+                try {
+                    $responseBody = (string) $response->getBody();
+                    preg_match('/sessionid[":\s]+([a-z\d]{32})/Ui', $responseBody, $matches);
+
+                    if (!isset($matches[1])) {
+                        // todo: locate an error message or set it as "undefined error".
+                        throw new RuntimeException('Unable to locate session identifier in the response.');
+                    }
+
+                    $sessionIdentifier = $matches[1];
+                    $sessionOpeningDeferred->resolve($sessionIdentifier);
+                } catch (Throwable $exception) {
+                    $reason = new RuntimeException(
+                        'Unable to open a selenium hub session (response deserialization).',
+                        0,
+                        $exception
+                    );
+
+                    $sessionOpeningDeferred->reject($reason);
+                }
+            },
+            function (Throwable $rejectionReason) use ($sessionOpeningDeferred) {
+                $reason = new RuntimeException('Unable to open a selenium hub session (request).', 0, $rejectionReason);
+
+                $sessionOpeningDeferred->reject($reason);
+            }
+        );
+
+        $sessionIdentifierPromise = $sessionOpeningDeferred->promise();
+
+        // todo: apply timeout
+
+        return $sessionIdentifierPromise;
     }
 
     /**

src/ClientInterface.php

@@ -38,7 +38,22 @@ public function getSessionIdentifiers(): PromiseInterface;
 
     /**
      * Returns a promise that resolves to a string, representing identifier of session that has been started by the
-     * remote WebDriver service
+     * remote WebDriver service.
+     *
+     * Usage example:
+     *
+     * ```
+     * $sessionIdentifierPromise = $webdriver->createSession();
+     *
+     * $sessionIdentifierPromise->then(
+     *     function (string $sessionIdentifier) {
+     *         // do some work
+     *     },
+     *     function (Throwable $rejectionReason) {
+     *         // handle exception
+     *     }
+     * );
+     * ```
      *
      * todo: argument to send desired capabilities, i.e. browser arguments and preferences (omitted)
      * todo: must also return a collection of confirmed browser capabilities (omitted)