diff --git a/lib/app/utils.js b/lib/app/utils.js index b2b9979a9a..a06d68f393 100644 --- a/lib/app/utils.js +++ b/lib/app/utils.js @@ -91,3 +91,235 @@ export function getLocation (base) { export function urlJoin () { return [].slice.call(arguments).join('/').replace(/\/+/g, '/') } + +// Imported from path-to-regexp + +/** + * Compile a string to a template function for the path. + * + * @param {string} str + * @param {Object=} options + * @return {!function(Object=, Object=)} + */ +export function compile (str, options) { + return tokensToFunction(parse(str, options)) +} + +/** + * The main path matching regexp utility. + * + * @type {RegExp} + */ +const PATH_REGEXP = new RegExp([ + // Match escaped characters that would otherwise appear in future matches. + // This allows the user to escape special characters that won't transform. + '(\\\\.)', + // Match Express-style parameters and un-named parameters with a prefix + // and optional suffixes. Matches appear as: + // + // "/:test(\\d+)?" => ["/", "test", "\d+", undefined, "?", undefined] + // "/route(\\d+)" => [undefined, undefined, undefined, "\d+", undefined, undefined] + // "/*" => ["/", undefined, undefined, undefined, undefined, "*"] + '([\\/.])?(?:(?:\\:(\\w+)(?:\\(((?:\\\\.|[^\\\\()])+)\\))?|\\(((?:\\\\.|[^\\\\()])+)\\))([+*?])?|(\\*))' +].join('|'), 'g') + +/** + * Parse a string for the raw tokens. + * + * @param {string} str + * @param {Object=} options + * @return {!Array} + */ +function parse (str, options) { + var tokens = [] + var key = 0 + var index = 0 + var path = '' + var defaultDelimiter = options && options.delimiter || '/' + var res + + while ((res = PATH_REGEXP.exec(str)) != null) { + var m = res[0] + var escaped = res[1] + var offset = res.index + path += str.slice(index, offset) + index = offset + m.length + + // Ignore already escaped sequences. + if (escaped) { + path += escaped[1] + continue + } + + var next = str[index] + var prefix = res[2] + var name = res[3] + var capture = res[4] + var group = res[5] + var modifier = res[6] + var asterisk = res[7] + + // Push the current path onto the tokens. + if (path) { + tokens.push(path) + path = '' + } + + var partial = prefix != null && next != null && next !== prefix + var repeat = modifier === '+' || modifier === '*' + var optional = modifier === '?' || modifier === '*' + var delimiter = res[2] || defaultDelimiter + var pattern = capture || group + + tokens.push({ + name: name || key++, + prefix: prefix || '', + delimiter: delimiter, + optional: optional, + repeat: repeat, + partial: partial, + asterisk: !!asterisk, + pattern: pattern ? escapeGroup(pattern) : (asterisk ? '.*' : '[^' + escapeString(delimiter) + ']+?') + }) + } + + // Match any characters still remaining. + if (index < str.length) { + path += str.substr(index) + } + + // If the path exists, push it onto the end. + if (path) { + tokens.push(path) + } + + return tokens +} + +/** + * Prettier encoding of URI path segments. + * + * @param {string} + * @return {string} + */ +function encodeURIComponentPretty (str) { + return encodeURI(str).replace(/[\/?#]/g, function (c) { + return '%' + c.charCodeAt(0).toString(16).toUpperCase() + }) +} + +/** + * Encode the asterisk parameter. Similar to `pretty`, but allows slashes. + * + * @param {string} + * @return {string} + */ +function encodeAsterisk (str) { + return encodeURI(str).replace(/[?#]/g, function (c) { + return '%' + c.charCodeAt(0).toString(16).toUpperCase() + }) +} + +/** + * Expose a method for transforming tokens into the path function. + */ +function tokensToFunction (tokens) { + // Compile all the tokens into regexps. + var matches = new Array(tokens.length) + + // Compile all the patterns before compilation. + for (var i = 0; i < tokens.length; i++) { + if (typeof tokens[i] === 'object') { + matches[i] = new RegExp('^(?:' + tokens[i].pattern + ')$') + } + } + + return function (obj, opts) { + var path = '' + var data = obj || {} + var options = opts || {} + var encode = options.pretty ? encodeURIComponentPretty : encodeURIComponent + + for (var i = 0; i < tokens.length; i++) { + var token = tokens[i] + + if (typeof token === 'string') { + path += token + + continue + } + + var value = data[token.name] + var segment + + if (value == null) { + if (token.optional) { + // Prepend partial segment prefixes. + if (token.partial) { + path += token.prefix + } + + continue + } else { + throw new TypeError('Expected "' + token.name + '" to be defined') + } + } + + if (Array.isArray(value)) { + if (!token.repeat) { + throw new TypeError('Expected "' + token.name + '" to not repeat, but received `' + JSON.stringify(value) + '`') + } + + if (value.length === 0) { + if (token.optional) { + continue + } else { + throw new TypeError('Expected "' + token.name + '" to not be empty') + } + } + + for (var j = 0; j < value.length; j++) { + segment = encode(value[j]) + + if (!matches[i].test(segment)) { + throw new TypeError('Expected all "' + token.name + '" to match "' + token.pattern + '", but received `' + JSON.stringify(segment) + '`') + } + + path += (j === 0 ? token.prefix : token.delimiter) + segment + } + + continue + } + + segment = token.asterisk ? encodeAsterisk(value) : encode(value) + + if (!matches[i].test(segment)) { + throw new TypeError('Expected "' + token.name + '" to match "' + token.pattern + '", but received "' + segment + '"') + } + + path += token.prefix + segment + } + + return path + } +} + +/** + * Escape a regular expression string. + * + * @param {string} str + * @return {string} + */ +function escapeString (str) { + return str.replace(/([.+*?=^!:${}()[\]|\/\\])/g, '\\$1') +} + +/** + * Escape the capturing group by escaping special characters and meaning. + * + * @param {string} group + * @return {string} + */ +function escapeGroup (group) { + return group.replace(/([=!:$\/()])/g, '\\$1') +}