Add new CacheStrategy & CacheMiddleware classes

example/shopify/inc/queries/class-shopify-add-to-cart-mutation.php

@@ -2,9 +2,9 @@
 
 namespace RemoteDataBlocks\Example\Shopify;
 
-use RemoteDataBlocks\Config\QueryContext\GraphqlQueryContext;
+use RemoteDataBlocks\Config\QueryContext\GraphqlMutationContext;
 
-class ShopifyAddToCartMutation extends GraphqlQueryContext {
+class ShopifyAddToCartMutation extends GraphqlMutationContext {
 	public function get_input_schema(): array {
 		return [
 			'cart_id'    => [
@@ -48,7 +48,7 @@ public function get_output_schema(): array {
 		];
 	}
 
-	public function get_query(): string {
+	public function get_mutation(): string {
 		return '
 			mutation AddProductToCart( $cart_id: ID!, $variant_id: ID!, $quantity: Int = 1 ){
 				cartLinesAdd(cartId: $cart_id, lines: [{ quantity: $quantity, merchandiseId: $variant_id }]) {

example/shopify/inc/queries/class-shopify-create-cart-mutation.php

@@ -2,9 +2,9 @@
 
 namespace RemoteDataBlocks\Example\Shopify;
 
-use RemoteDataBlocks\Config\QueryContext\GraphqlQueryContext;
+use RemoteDataBlocks\Config\QueryContext\GraphqlMutationContext;
 
-class ShopifyCreateCartMutation extends GraphqlQueryContext {
+class ShopifyCreateCartMutation extends GraphqlMutationContext {
 	public function get_output_schema(): array {
 		return [
 			'root_path'     => '$.data.cartCreate.cart',
@@ -24,7 +24,7 @@ public function get_output_schema(): array {
 		];
 	}
 
-	public function get_query(): string {
+	public function get_mutation(): string {
 		return '
 			mutation CreateShoppingCart {
 				cartCreate {

example/shopify/inc/queries/class-shopify-remove-from-cart-mutation.php

@@ -2,9 +2,9 @@
 
 namespace RemoteDataBlocks\Example\Shopify;
 
-use RemoteDataBlocks\Config\QueryContext\GraphqlQueryContext;
+use RemoteDataBlocks\Config\QueryContext\GraphqlMutationContext;
 
-class ShopifyRemoveFromCartMutation extends GraphqlQueryContext {
+class ShopifyRemoveFromCartMutation extends GraphqlMutationContext {
 	public function get_input_schema(): array {
 		return [
 			'cart_id' => [
@@ -45,7 +45,7 @@ public function get_output_schema(): array {
 		];
 	}
 
-	public function get_query(): string {
+	public function get_mutation(): string {
 		return '
 			mutation RemoveProductFromCart( $cart_id: ID!, $line_id: ID! ){
 				cartLinesAdd(cartId: $cart_id, lineIds: [ $line_id ] ) {

inc/Config/QueryContext/GraphqlMutationContext.php

@@ -0,0 +1,56 @@
+<?php declare(strict_types = 1);
+
+namespace RemoteDataBlocks\Config\QueryContext;
+
+defined( 'ABSPATH' ) || exit();
+
+/**
+ * Base class used to define a Remote Data Query. This class defines a
+ * composable query that allows it to be composed with another query or a block.
+ *
+ * @psalm-api
+ */
+abstract class GraphqlMutationContext extends HttpQueryContext {
+
+	/**
+	 * Override this method to define a custom request method for this mutation.
+	 */
+	public function get_request_method(): string {
+		return 'POST';
+	}
+
+	/**
+	 * Define this method to provide the GraphQL mutation document.
+	 *
+	 * @return string The GraphQL mutation document.
+	 */
+	abstract public function get_mutation(): string;
+
+	/**
+	 * Override this method to define the GraphQL mutation variables.
+	 *
+	 * @return array The GraphQL query variables.
+	 */
+	public function get_mutation_variables( array $input_variables ): array {
+		return $input_variables;
+	}
+
+	/**
+	 * Convert the mutation and variables into a GraphQL request body.
+	 */
+	public function get_request_body( array $input_variables ): array {
+		$variables = $this->get_mutation_variables( $input_variables );
+
+		return [
+			'query'     => $this->get_mutation(),
+			'variables' => empty( $variables ) ? null : $variables,
+		];
+	}
+
+	/**
+	 * GraphQL mutations are uncachable by default.
+	 */
+	public function get_cache_ttl( array $input_variables ): int {
+		return -1;
+	}
+}

inc/Config/QueryContext/GraphqlQueryContext.php

@@ -30,7 +30,7 @@ public function get_request_method(): string {
 	abstract public function get_query(): string;
 
 	/**
-	 * Override this method to define the GraphQL query document.
+	 * Override this method to define the GraphQL query variables.
 	 *
 	 * @return array The GraphQL query variables.
 	 */
@@ -49,4 +49,15 @@ public function get_request_body( array $input_variables ): array {
 			'variables' => empty( $variables ) ? null : $variables,
 		];
 	}
+
+	/**
+	 * Override this method to define the cache object TTL for this query. Return
+	 * -1 to disable caching. Return null to use the default cache TTL.
+	 *
+	 * @return int|null The cache object TTL in seconds.
+	 */
+	public function get_cache_ttl( array $input_variables ): ?int {
+		// Use default cache TTL.
+		return null;
+	}
 }

inc/Config/QueryContext/HttpQueryContext.php

@@ -144,6 +144,24 @@ public function get_query_runner(): QueryRunnerInterface {
 		return new QueryRunner( $this );
 	}
 
+	/**
+	 * Override this method to define the cache object TTL for this query. Return
+	 * -1 to disable caching. Return null to use the default cache TTL.
+	 *
+	 * @return int|null The cache object TTL in seconds.
+	 */
+	public function get_cache_ttl( array $input_variables ): null|int {
+		// For most HTTP requests, we only want to cache GET requests. This is
+		// overridden for GraphQL queries when using GraphqlQueryContext
+		if ( 'GET' !== strtoupper( $this->get_request_method() ) ) {
+			// Disable caching.
+			return -1;
+		}
+
+		// Use default cache TTL.
+		return null;
+	}
+
 	/**
 	 * Override this method to process the raw response data from the query before
 	 * it is passed to the query runner and the output variables are extracted. The

inc/Config/QueryContext/HttpQueryContextInterface.php

@@ -9,6 +9,7 @@
  * @since 0.1.0
  */
 interface HttpQueryContextInterface {
+	public function get_cache_ttl( array $input_variables ): null|int;
 	public function get_endpoint( array $input_variables ): string;
 	public function get_request_method(): string;
 	public function get_request_headers( array $input_variables ): array;

inc/Config/QueryRunner/QueryRunner.php

@@ -35,14 +35,16 @@ public function __construct(
 	 *   method: string,
 	 *   options: array<string, mixed>,
 	 *   origin: string,
+	 *   ttl: int|null,
 	 *   uri: string,
 	 * } The request details.
 	 */
 	protected function get_request_details( array $input_variables ): array|WP_Error {
-		$headers  = $this->query_context->get_request_headers( $input_variables );
-		$method   = $this->query_context->get_request_method();
-		$body     = $this->query_context->get_request_body( $input_variables );
-		$endpoint = $this->query_context->get_endpoint( $input_variables );
+		$headers   = $this->query_context->get_request_headers( $input_variables );
+		$method    = $this->query_context->get_request_method();
+		$body      = $this->query_context->get_request_body( $input_variables );
+		$endpoint  = $this->query_context->get_endpoint( $input_variables );
+		$cache_ttl = $this->query_context->get_cache_ttl( $input_variables );
 
 		$parsed_url = wp_parse_url( $endpoint );
 
@@ -80,12 +82,11 @@ protected function get_request_details( array $input_variables ): array|WP_Error
 		$request_details = [
 			'method'  => $method,
 			'options' => [
-				RequestOptions::HEADERS => array_merge( [
-					'User-Agent' => 'WordPress Remote Data Blocks/1.0',
-				], $headers ),
+				RequestOptions::HEADERS => $headers,
 				RequestOptions::JSON    => $body,
 			],
 			'origin'  => sprintf( '%s://%s%s%s%s', $scheme, $user, $pass, $host, $port ),
+			'ttl'     => $cache_ttl,
 			'uri'     => sprintf( '%s%s', $path, $query ),
 		];
 
@@ -121,7 +122,11 @@ protected function get_raw_response_data( array $input_variables ): array|WP_Err
 			return $request_details;
 		}
 
-		$this->http_client->init( $request_details['origin'] );
+		$client_options = [
+			HttpClient::CACHE_TTL_CLIENT_OPTION_KEY => $request_details['ttl'],
+		];
+
+		$this->http_client->init( $request_details['origin'], [], $client_options );
 
 		try {
 			$response = $this->http_client->request( $request_details['method'], $request_details['uri'], $request_details['options'] );

inc/HttpClient/HttpClient.php

@@ -9,13 +9,14 @@
 use GuzzleHttp\MessageFormatter;
 use GuzzleHttp\Middleware;
 use GuzzleHttp\Promise\Utils;
-use Kevinrob\GuzzleCache\CacheMiddleware;
 use Kevinrob\GuzzleCache\KeyValueHttpHeader;
+use Kevinrob\GuzzleCache\Storage\CacheStorageInterface;
 use Kevinrob\GuzzleCache\Storage\WordPressObjectCacheStorage;
-use Kevinrob\GuzzleCache\Strategy\GreedyCacheStrategy;
 use Psr\Http\Message\RequestInterface;
 use Psr\Http\Message\ResponseInterface;
 use Psr\Http\Message\UriInterface;
+use RemoteDataBlocks\HttpClient\RdbCacheStrategy;
+use RemoteDataBlocks\HttpClient\RdbCacheMiddleware;
 use RemoteDataBlocks\Logging\LoggerManager;
 
 defined( 'ABSPATH' ) || exit();
@@ -24,10 +25,12 @@ class HttpClient {
 	public Client $client;
 
 	private const MAX_RETRIES                        = 3;
-	private const CACHE_TTL_IN_SECONDS               = 60;
+	private const FALLBACK_CACHE_TTL_IN_SECONDS      = 60;
 	private const WP_OBJECT_CACHE_GROUP              = 'remote-data-blocks';
 	private const CACHE_INVALIDATING_REQUEST_HEADERS = [ 'Authorization', 'Cache-Control' ];
 
+	public const CACHE_TTL_CLIENT_OPTION_KEY = '__default_cache_ttl';
+
 	private string $base_uri;
 	private HandlerStack $handler_stack;
 
@@ -55,13 +58,31 @@ class HttpClient {
 	 */
 	private array $queued_requests = [];
 
+	public static function get_cache_storage(): CacheStorageInterface {
+		return new WordPressObjectCacheStorage( self::WP_OBJECT_CACHE_GROUP );
+	}
+
+	/**
+	 * Get the cache middleware for the HTTP client.
+	 *
+	 */
+	public static function get_cache_middleware( CacheStorageInterface $cache_storage, int|null $default_ttl = null ): callable {
+		return new RdbCacheMiddleware(
+			new RdbCacheStrategy(
+				$cache_storage,
+				$default_ttl ?? self::FALLBACK_CACHE_TTL_IN_SECONDS,
+				new KeyValueHttpHeader( self::CACHE_INVALIDATING_REQUEST_HEADERS )
+			)
+		);
+	}
+
 	/**
 	 * Initialize the HTTP client.
 	 */
-	public function init( string $base_uri, array $headers = [], array $options = [] ): void {
+	public function init( string $base_uri, array $headers = [], array $client_options = [] ): void {
 		$this->base_uri = $base_uri;
 		$this->headers  = $headers;
-		$this->options  = $options;
+		$this->options  = $client_options;
 
 		// Initialize a request handler that uses wp_remote_request instead of cURL.
 		// PHP cURL bindings are not always available, e.g., in WASM environments
@@ -83,16 +104,9 @@ public function init( string $base_uri, array $headers = [], array $options = []
 			return $request;
 		} ) );
 
-		$this->handler_stack->push(
-			new CacheMiddleware(
-				new GreedyCacheStrategy(
-					new WordPressObjectCacheStorage( self::WP_OBJECT_CACHE_GROUP ),
-					self::CACHE_TTL_IN_SECONDS,
-					new KeyValueHttpHeader( self::CACHE_INVALIDATING_REQUEST_HEADERS )
-				)
-			),
-			'remote_data_blocks_cache'
-		);
+		$default_ttl      = $client_options[ self::CACHE_TTL_CLIENT_OPTION_KEY ] ?? null;
+		$cache_middleware = self::get_cache_middleware( self::get_cache_storage(), $default_ttl );
+		$this->handler_stack->push( $cache_middleware, 'remote_data_blocks_cache' );
 
 		$this->handler_stack->push( Middleware::log(
 			LoggerManager::instance(),

inc/HttpClient/RdbCacheMiddleware.php

@@ -0,0 +1,14 @@
+<?php declare(strict_types = 1);
+
+namespace RemoteDataBlocks\HttpClient;
+
+class RdbCacheMiddleware extends \Kevinrob\GuzzleCache\CacheMiddleware {
+	/**
+	 * @var array<string, bool>
+	 */
+	// phpcs:ignore WordPress.NamingConventions.ValidVariableName.PropertyNotSnakeCase, SlevomatCodingStandard.TypeHints.PropertyTypeHint.MissingNativeTypeHint
+	protected $httpMethods = [
+		'GET'  => true,
+		'POST' => true,
+	];
+}