feat: Add support for token based pagination strategy (#887)

Author: tiwarishubham635

src/Twilio/Exceptions/KeyErrorException.php

@@ -0,0 +1,19 @@
+<?php
+
+
+namespace Twilio\Exceptions;
+
+
+/**
+ * Exception thrown when a required key is missing from a response or metadata.
+ *
+ * This exception is typically thrown when the expected 'key' field is not present
+ * in the response data or metadata, which may indicate a malformed or incomplete response.
+ *
+ * Example scenarios:
+ * - When parsing API responses and the 'key' field is missing.
+ * - When validating metadata and a required key is not found.
+ */
+class KeyErrorException extends TwilioException {
+
+}

src/Twilio/TokenPaginationPage.php

@@ -0,0 +1,139 @@
+<?php
+
+
+namespace Twilio;
+
+
+use Twilio\Exceptions\KeyErrorException;
+use Twilio\Http\Response;
+
+/**
+ * TokenPaginationPage is an abstract base class for handling paginated API responses
+ * that use token-based pagination rather than traditional page numbers. These are part of
+ * the new Twilio API Standards V1.
+ *
+ * Unlike the base {@see Page} class, which typically uses page numbers and URLs for navigation,
+ * TokenPaginationPage manages pagination using tokens (e.g., nextToken, previousToken) provided
+ * in the API response metadata. This allows for more flexible and scalable pagination, especially
+ * for APIs that do not support offset-based pagination.
+ *
+ * Example expected response format with token metadata:
+ * {
+ *   "meta": {
+ *     "key": "items",
+ *     "pageSize": 50,
+ *     "nextToken": "abc123",
+ *     "previousToken": "xyz789"
+ *   },
+ *   "items": [
+ *     { "id": 1, "name": "Item 1" },
+ *     { "id": 2, "name": "Item 2" }
+ *     // ...
+ *   ]
+ * }
+ *
+ */
+abstract class TokenPaginationPage extends Page {
+
+    protected $key;
+    protected $pageSize;
+    protected $nextToken;
+    protected $previousToken;
+    protected $url;
+    protected $previousPageUrl;
+    protected $nextPageUrl;
+
+    /**
+     * TokenPaginationPage constructor.
+     *
+     * @param Version $version The API version object.
+     * @param Response $response The HTTP response object.
+     * @throws KeyErrorException If the 'key' metadata is missing.
+     */
+    public function __construct(Version $version, Response $response) {
+        parent::__construct($version, $response);
+
+        $httpClient = $version->getDomain()->getClient()->getHttpClient();
+
+        $this->url = '';
+        if ($httpClient->lastRequest) {
+            $fullUrl = $httpClient->lastRequest[CURLOPT_URL];
+            // remove query parameters from url
+            $parts = explode('?', $fullUrl);
+            $this->url = $parts[0];
+        }
+
+        $this->key = $this->getMeta('key');
+        $this->pageSize = (int) $this->getMeta('pageSize');
+        $this->nextToken = $this->getMeta('nextToken');
+        $this->previousToken = $this->getMeta('previousToken');
+    }
+
+    /**
+     * Load the current page of records based on the 'key' metadata.
+     *
+     * @return array Array of records from the current page.
+     * @throws KeyErrorException If the 'key' metadata is missing.
+     */
+    protected function loadPage(): array {
+        $this->key = $this->getMeta('key');
+        if ($this->key) {
+            return $this->payload[$this->key];
+        }
+
+        throw new KeyErrorException('key not found in the response');
+    }
+
+    /**
+     * Construct the query string for pagination URLs.
+     *
+     * @param string|null $pageToken The token for the desired page.
+     * @return string The constructed query string.
+     */
+    protected function getQueryString(?string $pageToken): string {
+        $params = [];
+        if ($this->pageSize) {
+            $params['pageSize'] = $this->pageSize;
+        }
+        if ($pageToken !== null && $pageToken !== '') {
+            $params['pageToken'] = $pageToken;
+        }
+        $queryString = http_build_query($params);
+        return $queryString ? '?' . $queryString : '';
+    }
+
+    /**
+     * Get the URL for the previous page of results.
+     *
+     * @return string|null The URL for the previous page, or null if there is no previous page.
+     */
+    public function getPreviousPageUrl(): ?string {
+        if (!$this->previousToken) {
+            return null;
+        }
+        if (!$this->previousPageUrl) {
+            $this->previousPageUrl = $this->url . $this->getQueryString($this->previousToken);
+        }
+        return $this->previousPageUrl;
+    }
+
+    /**
+     * Get the URL for the next page of results.
+     *
+     * @return string|null The URL for the next page, or null if there is no next page.
+     */
+    public function getNextPageUrl(): ?string {
+        if (!$this->nextToken) {
+            return null;
+        }
+        if (!$this->nextPageUrl) {
+            $this->nextPageUrl = $this->url . $this->getQueryString($this->nextToken);
+        }
+        return $this->nextPageUrl;
+    }
+
+    public function __toString(): string {
+        return '[TokenPaginationPage]';
+    }
+
+}