Source

File: wp-admin/includes/translation-install.php

function translations_api( $type, $args = null ) {
	// Include an unmodified $wp_version.
	require ABSPATH . WPINC . '/version.php';

	if ( ! in_array( $type, array( 'plugins', 'themes', 'core' ), true ) ) {
		return new WP_Error( 'invalid_type', __( 'Invalid translation type.' ) );
	}

	/**
	 * Allows a plugin to override the WordPress.org Translation Installation API entirely.
	 *
	 * @since 4.0.0
	 *
	 * @param bool|array  $result The result object. Default false.
	 * @param string      $type   The type of translations being requested.
	 * @param object      $args   Translation API arguments.
	 */
	$res = apply_filters( 'translations_api', false, $type, $args );

	if ( false === $res ) {
		$url      = 'http://api.wordpress.org/translations/' . $type . '/1.0/';
		$http_url = $url;
		$ssl      = wp_http_supports( array( 'ssl' ) );
		if ( $ssl ) {
			$url = set_url_scheme( $url, 'https' );
		}

		$options = array(
			'timeout' => 3,
			'body'    => array(
				'wp_version' => $wp_version,
				'locale'     => get_locale(),
				'version'    => $args['version'], // Version of plugin, theme or core.
			),
		);

		if ( 'core' !== $type ) {
			$options['body']['slug'] = $args['slug']; // Plugin or theme slug.
		}

		$request = wp_remote_post( $url, $options );

		if ( $ssl && is_wp_error( $request ) ) {
			trigger_error(
				sprintf(
					/* translators: %s: Support forums URL. */
					__( 'An unexpected error occurred. Something may be wrong with WordPress.org or this server&#8217;s configuration. If you continue to have problems, please try the <a href="%s">support forums</a>.' ),
					__( 'https://wordpress.org/support/forums/' )
				) . ' ' . __( '(WordPress could not establish a secure connection to WordPress.org. Please contact your server administrator.)' ),
				headers_sent() || WP_DEBUG ? E_USER_WARNING : E_USER_NOTICE
			);

			$request = wp_remote_post( $http_url, $options );
		}

		if ( is_wp_error( $request ) ) {
			$res = new WP_Error(
				'translations_api_failed',
				sprintf(
					/* translators: %s: Support forums URL. */
					__( 'An unexpected error occurred. Something may be wrong with WordPress.org or this server&#8217;s configuration. If you continue to have problems, please try the <a href="%s">support forums</a>.' ),
					__( 'https://wordpress.org/support/forums/' )
				),
				$request->get_error_message()
			);
		} else {
			$res = json_decode( wp_remote_retrieve_body( $request ), true );
			if ( ! is_object( $res ) && ! is_array( $res ) ) {
				$res = new WP_Error(
					'translations_api_failed',
					sprintf(
						/* translators: %s: Support forums URL. */
						__( 'An unexpected error occurred. Something may be wrong with WordPress.org or this server&#8217;s configuration. If you continue to have problems, please try the <a href="%s">support forums</a>.' ),
						__( 'https://wordpress.org/support/forums/' )
					),
					wp_remote_retrieve_body( $request )
				);
			}
		}
	}

	/**
	 * Filters the Translation Installation API response results.
	 *
	 * @since 4.0.0
	 *
	 * @param object|WP_Error $res  Response object or WP_Error.
	 * @param string          $type The type of translations being requested.
	 * @param object          $args Translation API arguments.
	 */
	return apply_filters( 'translations_api_result', $res, $type, $args );
}