Add CSV upload helper

plugins/woocommerce/src/Container.php

@@ -32,6 +32,7 @@ use Automattic\WooCommerce\Internal\DependencyManagement\ServiceProviders\BatchP
 use Automattic\WooCommerce\Internal\DependencyManagement\ServiceProviders\LayoutTemplatesServiceProvider;
 use Automattic\WooCommerce\Internal\DependencyManagement\ServiceProviders\ComingSoonServiceProvider;
 use Automattic\WooCommerce\Internal\DependencyManagement\ServiceProviders\StatsServiceProvider;
+use Automattic\WooCommerce\Internal\DependencyManagement\ServiceProviders\ImportExportServiceProvider;
 
 /**
  * PSR11 compliant dependency injection container for WooCommerce.
@@ -83,6 +84,7 @@ final class Container {
 		EnginesServiceProvider::class,
 		ComingSoonServiceProvider::class,
 		StatsServiceProvider::class,
+		ImportExportServiceProvider::class,
 	);
 
 	/**

plugins/woocommerce/src/Internal/Admin/ImportExport/CSVUploadHelper.php

@@ -0,0 +1,175 @@
+<?php
+declare( strict_types = 1 );
+
+namespace Automattic\WooCommerce\Internal\Admin\ImportExport;
+
+use Automattic\WooCommerce\Internal\Traits\AccessiblePrivateMethods;
+use Automattic\WooCommerce\Internal\Utilities\FilesystemUtil;
+
+/**
+ * Helper for CSV import functionality.
+ *
+ * @since 9.3.0
+ */
+class CSVUploadHelper {
+
+	use AccessiblePrivateMethods;
+
+	/**
+	 * Name (inside the uploads folder) to use for the CSV import directory.
+	 *
+	 * @return string
+	 */
+	protected function get_import_subdir_name(): string {
+		return 'wc-imports';
+	}
+
+	/**
+	 * Returns the full path to the CSV import directory within the uploads folder.
+	 * It will attempt to create the directory if it doesn't exist.
+	 *
+	 * @param bool $create TRUE to attempt to create the directory. FALSE otherwise.
+	 * @return string
+	 * @throws \Exception In case the upload directory doesn't exits or can't be created.
+	 */
+	public function get_import_dir( bool $create = true ): string {
+		$wp_upload_dir = wp_upload_dir( null, $create );
+		if ( $wp_upload_dir['error'] ) {
+			throw new \Exception( esc_html( $wp_upload_dir['error'] ) );
+		}
+
+		$upload_dir = trailingslashit( $wp_upload_dir['basedir'] ) . $this->get_import_subdir_name();
+		if ( $create ) {
+			FilesystemUtil::mkdir_p_not_indexable( $upload_dir );
+		}
+		return $upload_dir;
+	}
+
+	/**
+	 * Handles a CSV file upload.
+	 *
+	 * @param string     $import_type        Type of upload or context.
+	 * @param string     $files_index        $_FILES index that contains the file to upload.
+	 * @param array|null $allowed_mime_types List of allowed MIME types.
+	 * @return array {
+	 *     Details for the uploaded file.
+	 *
+	 *     @type int    $id   Attachment ID.
+	 *     @type string $file Full path to uploaded file.
+	 * }
+	 *
+	 * @throws \Exception In case of error.
+	 */
+	public function handle_csv_upload( string $import_type, string $files_index = 'import', ?array $allowed_mime_types = null ): array {
+		$import_type = sanitize_key( $import_type );
+		if ( ! $import_type ) {
+			throw new \Exception( 'Import type is invalid.' );
+		}
+
+		if ( ! $allowed_mime_types ) {
+			$allowed_mime_types = array(
+				'csv' => 'text/csv',
+				'txt' => 'text/plain',
+			);
+		}
+
+		$file = $_FILES[ $files_index ] ?? null; // phpcs:ignore WordPress.Security.ValidatedSanitizedInput.InputNotSanitized,WordPress.Security.NonceVerification.Missing
+		if ( ! isset( $file['tmp_name'] ) || ! is_uploaded_file( $file['tmp_name'] ) ) {
+			throw new \Exception( esc_html__( 'File is empty. Please upload something more substantial. This error could also be caused by uploads being disabled in your php.ini or by post_max_size being defined as smaller than upload_max_filesize in php.ini.', 'woocommerce' ) );
+		}
+
+		if ( ! function_exists( 'wp_import_handle_upload' ) ) {
+			require_once ABSPATH . 'wp-admin/includes/import.php';
+		}
+
+		// Make sure upload dir exists.
+		$this->get_import_dir();
+
+		// Add prefix.
+		$file['name'] = $import_type . '-' . $file['name'];
+
+		$overrides_callback = function ( $overrides_ ) use ( $allowed_mime_types ) {
+			$overrides_['test_form'] = false;
+			$overrides_['test_type'] = true;
+			$overrides_['mimes']     = $allowed_mime_types;
+			return $overrides_;
+		};
+
+		self::add_filter( 'upload_dir', array( $this, 'override_upload_dir' ) );
+		self::add_filter( 'wp_unique_filename', array( $this, 'override_unique_filename' ), 0, 2 );
+		self::add_filter( 'wp_handle_upload_overrides', $overrides_callback, 999 );
+		self::add_filter( 'wp_handle_upload_prefilter', array( $this, 'remove_txt_from_uploaded_file' ), 0 );
+
+		$orig_files_import = $_FILES['import'] ?? null; // phpcs:ignore WordPress.Security.ValidatedSanitizedInput.InputNotSanitized,WordPress.Security.NonceVerification.Missing
+		$_FILES['import']  = $file;  // wp_import_handle_upload() expects the file to be in 'import'.
+
+		$upload = wp_import_handle_upload();
+
+		remove_filter( 'upload_dir', array( $this, 'override_upload_dir' ) );
+		remove_filter( 'wp_unique_filename', array( $this, 'override_unique_filename' ), 0 );
+		remove_filter( 'wp_handle_upload_overrides', $overrides_callback, 999 );
+		remove_filter( 'wp_handle_upload_prefilter', array( $this, 'remove_txt_from_uploaded_file' ), 0 );
+
+		if ( $orig_files_import ) {
+			$_FILES['import'] = $orig_files_import;
+		} else {
+			unset( $_FILES['import'] );
+		}
+
+		if ( ! empty( $upload['error'] ) ) {
+			throw new \Exception( esc_html( $upload['error'] ) );
+		}
+
+		if ( ! wc_is_file_valid_csv( $upload['file'], false ) ) {
+			wp_delete_attachment( $file['id'], true );
+			throw new \Exception( esc_html__( 'Invalid file type for a CSV import.', 'woocommerce' ) );
+		}
+
+		return $upload;
+	}
+
+	/**
+	 * Hooked onto 'upload_dir' to override the default upload directory for a CSV upload.
+	 *
+	 * @param array $uploads WP upload dir details.
+	 * @return array
+	 */
+	private function override_upload_dir( $uploads ): array {
+		$new_subdir = '/' . $this->get_import_subdir_name();
+
+		$uploads['path']   = $uploads['basedir'] . $new_subdir;
+		$uploads['url']    = $uploads['baseurl'] . $new_subdir;
+		$uploads['subdir'] = $new_subdir;
+
+		return $uploads;
+	}
+
+	/**
+	 * Adds a random string to the name of an uploaded CSV file to make it less discoverable. Hooked onto 'wp_unique_filename'.
+	 *
+	 * @param string $filename File name.
+	 * @param string $ext      File extension.
+	 * @return string
+	 */
+	private function override_unique_filename( string $filename, string $ext ): string {
+		$length = min( 10, 255 - strlen( $filename ) - 1 );
+		if ( 1 < $length ) {
+			$suffix   = strtolower( wp_generate_password( $length, false, false ) );
+			$filename = substr( $filename, 0, strlen( $filename ) - strlen( $ext ) ) . '-' . $suffix . $ext;
+		}
+
+		return $filename;
+	}
+
+	/**
+	 * `wp_import_handle_upload()` appends .txt to any file name. This function is hooked onto 'wp_handle_upload_prefilter'
+	 * to remove those extra characters.
+	 *
+	 * @param array $file File details in the form of a $_FILES entry.
+	 * @return array Modified file details.
+	 */
+	private function remove_txt_from_uploaded_file( array $file ): array {
+		$file['name'] = substr( $file['name'], 0, -4 );
+		return $file;
+	}
+}

plugins/woocommerce/src/Internal/DependencyManagement/ServiceProviders/ImportExportServiceProvider.php

@@ -0,0 +1,35 @@
+<?php
+/**
+ * ImportExportServiceProvider class file.
+ */
+
+declare( strict_types = 1 );
+
+namespace Automattic\WooCommerce\Internal\DependencyManagement\ServiceProviders;
+
+use Automattic\WooCommerce\Internal\Admin\ImportExport\CSVUploadHelper;
+use Automattic\WooCommerce\Internal\DependencyManagement\AbstractServiceProvider;
+
+/**
+ * Service provider for the import/export classes.
+ *
+ * @since 9.3.0
+ */
+class ImportExportServiceProvider extends AbstractServiceProvider {
+
+	/**
+	 * The classes/interfaces that are serviced by this service provider.
+	 *
+	 * @var array
+	 */
+	protected $provides = array(
+		CSVUploadHelper::class,
+	);
+
+	/**
+	 * Register the classes.
+	 */
+	public function register() {
+		$this->share( CSVUploadHelper::class );
+	}
+}