Add product attribute filter to Orders Report. (https://github.com/woocommerce/woocommerce-admin/pull/5068)

* Add product attribute filter to Orders report config.

* Add attribute args to Orders report controller.

* Include attribute filters in orders report query.

* Add attribute args to Orders Stats report controller.

* Include attribute filters in orders report stats query.

* Add test for product attribute filter in orders report.

* Add tests for invalid parameter values.

* Add tests for product attribute filter in order stats endpoint.

* Fix tests for PHP 5.6 and WC 3.8.x.

plugins/woocommerce-admin/client/analytics/report/orders/config.js

@@ -310,6 +310,50 @@ export const advancedFilters = applyFilters(
 					getLabels: getTaxRateLabels,
 				},
 			},
+			attribute: {
+				allowMultiple: true,
+				labels: {
+					add: __( 'Attribute', 'woocommerce-admin' ),
+					placeholder: __( 'Search attributes', 'woocommerce-admin' ),
+					remove: __(
+						'Remove attribute filter',
+						'woocommerce-admin'
+					),
+					rule: __(
+						'Select a product attribute filter match',
+						'woocommerce-admin'
+					),
+					/* translators: A sentence describing a Product filter. See screen shot for context: https://cloudup.com/cSsUY9VeCVJ */
+					title: __(
+						'{{title}}Attribute{{/title}} {{rule /}} {{filter /}}',
+						'woocommerce-admin'
+					),
+					filter: __( 'Select attributes', 'woocommerce-admin' ),
+				},
+				rules: [
+					{
+						value: 'is',
+						/* translators: Sentence fragment, logical, "Is" refers to searching for products matching a chosen attribute. Screenshot for context: https://cloudup.com/cSsUY9VeCVJ */
+						label: _x(
+							'Is',
+							'product attribute',
+							'woocommerce-admin'
+						),
+					},
+					{
+						value: 'is_not',
+						/* translators: Sentence fragment, logical, "Is Not" refers to searching for products that don\'t match a chosen attribute. Screenshot for context: https://cloudup.com/cSsUY9VeCVJ */
+						label: _x(
+							'Is Not',
+							'product attribute',
+							'woocommerce-admin'
+						),
+					},
+				],
+				input: {
+					component: 'ProductAttribute',
+				},
+			},
 		},
 	}
 );

plugins/woocommerce-admin/src/API/Reports/DataStore.php

@@ -1179,6 +1179,78 @@ class DataStore extends SqlQuery {
 		return $customer_filter;
 	}
 
+	/**
+	 * Returns product attribute subquery elements used in JOIN and WHERE clauses,
+	 * based on query arguments from the user.
+	 *
+	 * @param array $query_args Parameters supplied by the user.
+	 * @return array
+	 */
+	protected function get_attribute_subqueries( $query_args ) {
+		global $wpdb;
+
+		$sql_clauses           = array(
+			'join'  => array(),
+			'where' => array(),
+		);
+		$match_operator        = $this->get_match_operator( $query_args );
+		$join_table            = $wpdb->prefix . 'wc_order_product_lookup';
+		$post_meta_comparators = array(
+			'='  => 'attribute_is',
+			'!=' => 'attribute_is_not',
+		);
+
+		foreach ( $post_meta_comparators as $comparator => $arg ) {
+			if ( ! isset( $query_args[ $arg ] ) || ! is_array( $query_args[ $arg ] ) ) {
+				continue;
+			}
+			foreach ( $query_args[ $arg ] as $attribute_term ) {
+				// We expect tuples of IDs.
+				if ( ! is_array( $attribute_term ) || 2 !== count( $attribute_term ) ) {
+					continue;
+				}
+
+				$attribute_id = intval( $attribute_term[0] );
+				$term_id      = intval( $attribute_term[1] );
+
+				// Tuple, but non-numeric.
+				if ( 0 === $attribute_id || 0 === $term_id ) {
+					continue;
+				}
+
+				// @todo: Use wc_get_attribute() instead ?
+				$attr_taxonomy = wc_attribute_taxonomy_name_by_id( $attribute_id );
+				// Invalid attribute ID.
+				if ( empty( $attr_taxonomy ) ) {
+					continue;
+				}
+
+				$attr_term = get_term_by( 'id', $term_id, $attr_taxonomy );
+				// Invalid term ID.
+				if ( false === $attr_term ) {
+					continue;
+				}
+
+				$meta_key   = wc_variation_attribute_name( $attr_taxonomy );
+				$meta_value = $attr_term->slug;
+				$join_alias = 'wpm1';
+
+				// If we're matching all filters (AND), we'll need multiple JOINs on postmeta.
+				// If not, just one.
+				if ( 'AND' === $match_operator || empty( $sql_clauses['join'] ) ) {
+					$join_idx              = count( $sql_clauses['join'] ) + 1;
+					$join_alias            = 'wpm' . $join_idx;
+					$sql_clauses['join'][] = "JOIN {$wpdb->postmeta} as {$join_alias} ON {$join_alias}.post_id = {$join_table}.variation_id";
+				}
+
+				// phpcs:ignore WordPress.DB.PreparedSQL.InterpolatedNotPrepared
+				$sql_clauses['where'][] = $wpdb->prepare( "( {$join_alias}.meta_key = %s AND {$join_alias}.meta_value {$comparator} %s )", $meta_key, $meta_value );
+			}
+		}
+
+		return $sql_clauses;
+	}
+
 	/**
 	 * Returns logic operator for WHERE subclause based on 'match' query argument.
 	 *

plugins/woocommerce-admin/src/API/Reports/Orders/Controller.php

@@ -61,6 +61,8 @@ class Controller extends ReportsController implements ExportableInterface {
 		$args['match']             = $request['match'];
 		$args['order_includes']    = $request['order_includes'];
 		$args['order_excludes']    = $request['order_excludes'];
+		$args['attribute_is']      = (array) $request['attribute_is'];
+		$args['attribute_is_not']  = (array) $request['attribute_is_not'];
 
 		return $args;
 	}
@@ -429,6 +431,24 @@ class Controller extends ReportsController implements ExportableInterface {
 				'type' => 'integer',
 			),
 		);
+		$params['attribute_is']      = array(
+			'description'       => __( 'Limit result set to orders that include products with the specified attributes.', 'woocommerce-admin' ),
+			'type'              => 'array',
+			'items'             => array(
+				'type' => 'array',
+			),
+			'default'           => array(),
+			'validate_callback' => 'rest_validate_request_arg',
+		);
+		$params['attribute_is_not']  = array(
+			'description'       => __( 'Limit result set to orders that don\'t include products with the specified attributes.', 'woocommerce-admin' ),
+			'type'              => 'array',
+			'items'             => array(
+				'type' => 'array',
+			),
+			'default'           => array(),
+			'validate_callback' => 'rest_validate_request_arg',
+		);
 
 		return $params;
 	}

plugins/woocommerce-admin/src/API/Reports/Orders/DataStore.php

@@ -160,6 +160,20 @@ class DataStore extends ReportsDataStore implements DataStoreInterface {
 			$where_subquery[] = "{$order_tax_lookup_table}.tax_rate_id NOT IN ({$excluded_tax_rates}) OR {$order_tax_lookup_table}.tax_rate_id IS NULL";
 		}
 
+		$attribute_subqueries = $this->get_attribute_subqueries( $query_args );
+		if ( $attribute_subqueries['join'] && $attribute_subqueries['where'] ) {
+			// JOIN on product lookup if we haven't already.
+			if ( ! $included_products && ! $excluded_products ) {
+				$this->subquery->add_sql_clause( 'join', "JOIN {$order_product_lookup_table} ON {$order_stats_lookup_table}.order_id = {$order_product_lookup_table}.order_id" );
+			}
+			// Add JOINs for matching attributes.
+			foreach ( $attribute_subqueries['join'] as $attribute_join ) {
+				$this->subquery->add_sql_clause( 'join', $attribute_join );
+			}
+			// Add WHEREs for matching attributes.
+			$where_subquery = array_merge( $where_subquery, $attribute_subqueries['where'] );
+		}
+
 		if ( 0 < count( $where_subquery ) ) {
 			$this->subquery->add_sql_clause( 'where', 'AND (' . implode( " {$operator} ", $where_subquery ) . ')' );
 		}

plugins/woocommerce-admin/src/API/Reports/Orders/Stats/Controller.php

@@ -59,6 +59,8 @@ class Controller extends \Automattic\WooCommerce\Admin\API\Reports\Controller {
 		$args['tax_rate_excludes'] = (array) $request['tax_rate_excludes'];
 		$args['customer']          = $request['customer'];
 		$args['refunds']           = $request['refunds'];
+		$args['attribute_is']      = (array) $request['attribute_is'];
+		$args['attribute_is_not']  = (array) $request['attribute_is_not'];
 		$args['categories']        = (array) $request['categories'];
 		$args['segmentby']         = $request['segmentby'];
 
@@ -492,6 +494,24 @@ class Controller extends \Automattic\WooCommerce\Admin\API\Reports\Controller {
 			),
 			'validate_callback' => 'rest_validate_request_arg',
 		);
+		$params['attribute_is']      = array(
+			'description'       => __( 'Limit result set to orders that include products with the specified attributes.', 'woocommerce-admin' ),
+			'type'              => 'array',
+			'items'             => array(
+				'type' => 'array',
+			),
+			'default'           => array(),
+			'validate_callback' => 'rest_validate_request_arg',
+		);
+		$params['attribute_is_not']  = array(
+			'description'       => __( 'Limit result set to orders that don\'t include products with the specified attributes.', 'woocommerce-admin' ),
+			'type'              => 'array',
+			'items'             => array(
+				'type' => 'array',
+			),
+			'default'           => array(),
+			'validate_callback' => 'rest_validate_request_arg',
+		);
 		$params['segmentby']         = array(
 			'description'       => __( 'Segment the response by additional constraint.', 'woocommerce-admin' ),
 			'type'              => 'string',

plugins/woocommerce-admin/src/API/Reports/Orders/Stats/DataStore.php

@@ -178,6 +178,29 @@ class DataStore extends ReportsDataStore implements DataStoreInterface {
 			implode( ',', $query_args['tax_rate_excludes'] )
 		);
 
+		// Product attribute filters.
+		$attribute_subqueries = $this->get_attribute_subqueries( $query_args );
+		if ( $attribute_subqueries['join'] && $attribute_subqueries['where'] ) {
+			// Build a subquery for getting order IDs by product attribute(s).
+			// Done here since our use case is a little more complicated than get_object_where_filter() can handle.
+			$attribute_subquery = new SqlQuery();
+			$attribute_subquery->add_sql_clause( 'select', "{$orders_stats_table}.order_id" );
+			$attribute_subquery->add_sql_clause( 'from', $orders_stats_table );
+
+			// JOIN on product lookup.
+			$attribute_subquery->add_sql_clause( 'join', "JOIN {$product_lookup} ON {$orders_stats_table}.order_id = {$product_lookup}.order_id" );
+
+			// Add JOINs for matching attributes.
+			foreach ( $attribute_subqueries['join'] as $attribute_join ) {
+				$attribute_subquery->add_sql_clause( 'join', $attribute_join );
+			}
+			// Add WHEREs for matching attributes.
+			$attribute_subquery->add_sql_clause( 'where', 'AND (' . implode( " {$operator} ", $attribute_subqueries['where'] ) . ')' );
+
+			// Generate subquery statement and add to our where filters.
+			$where_filters[] = "{$orders_stats_table}.order_id IN (" . $attribute_subquery->get_query_statement() . ')';
+		}
+
 		$where_filters[] = $this->get_customer_subquery( $query_args );
 		$refund_subquery = $this->get_refund_subquery( $query_args );
 		$from_clause    .= $refund_subquery['from_clause'];

plugins/woocommerce-admin/tests/api/reports-orders-stats.php

@@ -127,4 +127,83 @@ class WC_Tests_API_Reports_Orders_Stats extends WC_REST_Unit_Test_Case {
 		$this->assertArrayHasKey( 'total_customers', $subtotals );
 		$this->assertArrayHasKey( 'segments', $subtotals );
 	}
+
+	/**
+	 * Test filtering by product attribute(s).
+	 */
+	public function test_product_attributes_filter() {
+		global $wpdb;
+		wp_set_current_user( $this->user );
+		WC_Helper_Reports::reset_stats_dbs();
+
+		// Create a variable product.
+		$variable_product   = WC_Helper_Product::create_variation_product( new WC_Product_Variable() );
+		$product_variations = $variable_product->get_children();
+		$order_variation_1  = wc_get_product( $product_variations[1] ); // Variation: size = large.
+		$order_variation_2  = wc_get_product( $product_variations[3] ); // Variation: size = huge, colour = red, number = 2.
+
+		// Create orders for variations.
+		$variation_order_1 = WC_Helper_Order::create_order( $this->user, $order_variation_1 );
+		$variation_order_1->set_status( 'completed' );
+		$variation_order_1->save();
+
+		$variation_order_2 = WC_Helper_Order::create_order( $this->user, $order_variation_2 );
+		$variation_order_2->set_status( 'completed' );
+		$variation_order_2->save();
+
+		// Create more orders for simple products.
+		for ( $i = 0; $i < 10; $i++ ) {
+			$order = WC_Helper_Order::create_order( $this->user );
+			$order->set_status( 'completed' );
+			$order->save();
+		}
+
+		WC_Helper_Queue::run_all_pending();
+
+		$request = new WP_REST_Request( 'GET', $this->endpoint );
+		$request->set_query_params( array( 'per_page' => 15 ) );
+		$response        = $this->server->dispatch( $request );
+		$response_orders = $response->get_data();
+
+		// Sanity check before filtering by attribute.
+		$this->assertEquals( 200, $response->get_status() );
+		$this->assertEquals( 12, $response_orders['totals']['orders_count'] );
+
+		// Filter by the "size" attribute, with value "large".
+		$size_attr_id = wc_attribute_taxonomy_id_by_name( 'pa_size' );
+		$small_term   = get_term_by( 'slug', 'large', 'pa_size' );
+		$request      = new WP_REST_Request( 'GET', $this->endpoint );
+		$request->set_query_params(
+			array(
+				'attribute_is' => array(
+					array( $size_attr_id, $small_term->term_id ),
+				),
+			)
+		);
+		$response        = $this->server->dispatch( $request );
+		$response_orders = $response->get_data();
+
+		$this->assertEquals( 200, $response->get_status() );
+		$this->assertEquals( 1, $response_orders['totals']['orders_count'] );
+		$this->assertEquals( $variation_order_1->get_total(), $response_orders['totals']['total_sales'] );
+
+		// Filter by excluding the "size" attribute, with value "large".
+		$size_attr_id = wc_attribute_taxonomy_id_by_name( 'pa_size' );
+		$small_term   = get_term_by( 'slug', 'large', 'pa_size' );
+		$request      = new WP_REST_Request( 'GET', $this->endpoint );
+		$request->set_query_params(
+			array(
+				'attribute_is_not' => array(
+					array( $size_attr_id, $small_term->term_id ),
+				),
+			)
+		);
+		$response        = $this->server->dispatch( $request );
+		$response_orders = $response->get_data();
+
+		$this->assertEquals( 200, $response->get_status() );
+		$this->assertEquals( 1, $response_orders['totals']['orders_count'] );
+		// This should be the second variation order.
+		$this->assertEquals( $variation_order_2->get_total(), $response_orders['totals']['total_sales'] );
+	}
 }

plugins/woocommerce-admin/tests/api/reports-orders.php

@@ -128,4 +128,109 @@ class WC_Tests_API_Reports_Orders extends WC_REST_Unit_Test_Case {
 		$this->assertArrayHasKey( 'customer_type', $properties );
 		$this->assertArrayHasKey( 'extended_info', $properties );
 	}
+
+	/**
+	 * Test filtering by product attribute(s).
+	 */
+	public function test_product_attributes_filter() {
+		global $wpdb;
+		wp_set_current_user( $this->user );
+		WC_Helper_Reports::reset_stats_dbs();
+
+		// Create a variable product.
+		$variable_product   = WC_Helper_Product::create_variation_product( new WC_Product_Variable() );
+		$product_variations = $variable_product->get_children();
+		$order_variation_1  = wc_get_product( $product_variations[0] ); // Variation: size = small.
+		$order_variation_2  = wc_get_product( $product_variations[2] ); // Variation: size = huge, colour = red, number = 0.
+
+		// Create orders for variations.
+		$variation_order_1 = WC_Helper_Order::create_order( $this->user, $order_variation_1 );
+		$variation_order_1->set_status( 'completed' );
+		$variation_order_1->save();
+
+		$variation_order_2 = WC_Helper_Order::create_order( $this->user, $order_variation_2 );
+		$variation_order_2->set_status( 'completed' );
+		$variation_order_2->save();
+
+		// Create more orders for simple products.
+		for ( $i = 0; $i < 10; $i++ ) {
+			$order = WC_Helper_Order::create_order( $this->user );
+			$order->set_status( 'completed' );
+			$order->save();
+		}
+
+		WC_Helper_Queue::run_all_pending();
+
+		$request = new WP_REST_Request( 'GET', $this->endpoint );
+		$request->set_query_params( array( 'per_page' => 15 ) );
+		$response        = $this->server->dispatch( $request );
+		$response_orders = $response->get_data();
+
+		// Sanity check before filtering by attribute.
+		$this->assertEquals( 200, $response->get_status() );
+		$this->assertEquals( 12, count( $response_orders ) );
+
+		// To filter by later.
+		$size_attr_id = wc_attribute_taxonomy_id_by_name( 'pa_size' );
+		$small_term   = get_term_by( 'slug', 'small', 'pa_size' );
+
+		// Test bad values to filter parameter.
+		$bad_args = array(
+			'not an array!',                   // Not an array.
+			array( 1, 2, 3 ),                  // Not a tuple.
+			array( 'a', 1 ),                   // Non-numeric attribute ID.
+			array( 1, 'a' ),                   // Non-numeric term ID.
+			array( -1, $small_term->term_id ), // Invaid attribute ID.
+			array( $size_attr_id, -1 ),        // Invaid term ID.
+		);
+
+		foreach ( $bad_args as $bad_arg ) {
+			$request = new WP_REST_Request( 'GET', $this->endpoint );
+			$request->set_query_params(
+				array(
+					'per_page'     => 15,
+					'attribute_is' => $bad_arg,
+				)
+			);
+			$response        = $this->server->dispatch( $request );
+			$response_orders = $response->get_data();
+
+			$this->assertEquals( 200, $response->get_status() );
+			// We expect all results since the attribute param is malformed.
+			$this->assertEquals( 12, count( $response_orders ) );
+		}
+
+		// Filter by the "size" attribute, with value "small".
+		$request = new WP_REST_Request( 'GET', $this->endpoint );
+		$request->set_query_params(
+			array(
+				'attribute_is' => array(
+					array( $size_attr_id, $small_term->term_id ),
+				),
+			)
+		);
+		$response        = $this->server->dispatch( $request );
+		$response_orders = $response->get_data();
+
+		$this->assertEquals( 200, $response->get_status() );
+		$this->assertEquals( 1, count( $response_orders ) );
+		$this->assertEquals( $response_orders[0]['order_id'], $variation_order_1->get_id() );
+
+		// Verify the opposite result set.
+		$request = new WP_REST_Request( 'GET', $this->endpoint );
+		$request->set_query_params(
+			array(
+				'attribute_is_not' => array(
+					array( $size_attr_id, $small_term->term_id ),
+				),
+				'per_page'         => 15,
+			)
+		);
+		$response        = $this->server->dispatch( $request );
+		$response_orders = $response->get_data();
+
+		$this->assertEquals( 200, $response->get_status() );
+		$this->assertEquals( 1, count( $response_orders ) );
+		$this->assertEquals( $response_orders[0]['order_id'], $variation_order_2->get_id() );
+	}
 }