comparison node_modules/express/lib/utils.js @ 73:0c3a2942ddee

now using express to server static content

+/**
+ * Module dependencies.
+ */
+
+var mime = require('send').mime;
+var crc32 = require('buffer-crc32');
+var crypto = require('crypto');
+var basename = require('path').basename;
+var deprecate = require('util').deprecate;
+var proxyaddr = require('proxy-addr');
+
+/**
+ * Simple detection of charset parameter in content-type
+ */
+var charsetRegExp = /;\s*charset\s*=/;
+
+/**
+ * Deprecate function, like core `util.deprecate`,
+ * but with NODE_ENV and color support.
+ *
+ * @param {Function} fn
+ * @param {String} msg
+ * @return {Function}
+ * @api private
+ */
+
+exports.deprecate = function(fn, msg){
+  if (process.env.NODE_ENV === 'test') return fn;
+
+  // prepend module name
+  msg = 'express: ' + msg;
+
+  if (process.stderr.isTTY) {
+    // colorize
+    msg = '\x1b[31;1m' + msg + '\x1b[0m';
+  }
+
+  return deprecate(fn, msg);
+};
+
+/**
+ * Return strong ETag for `body`.
+ *
+ * @param {String|Buffer} body
+ * @param {String} [encoding]
+ * @return {String}
+ * @api private
+ */
+
+exports.etag = function etag(body, encoding){
+  if (body.length === 0) {
+    // fast-path empty body
+    return '"1B2M2Y8AsgTpgAmY7PhCfg=="'
+  }
+
+  var hash = crypto
+    .createHash('md5')
+    .update(body, encoding)
+    .digest('base64')
+  return '"' + hash + '"'
+};
+
+/**
+ * Return weak ETag for `body`.
+ *
+ * @param {String|Buffer} body
+ * @param {String} [encoding]
+ * @return {String}
+ * @api private
+ */
+
+exports.wetag = function wetag(body, encoding){
+  if (body.length === 0) {
+    // fast-path empty body
+    return 'W/"0-0"'
+  }
+
+  var buf = Buffer.isBuffer(body)
+    ? body
+    : new Buffer(body, encoding)
+  var len = buf.length
+  return 'W/"' + len.toString(16) + '-' + crc32.unsigned(buf) + '"'
+};
+
+/**
+ * Check if `path` looks absolute.
+ *
+ * @param {String} path
+ * @return {Boolean}
+ * @api private
+ */
+
+exports.isAbsolute = function(path){
+  if ('/' == path[0]) return true;
+  if (':' == path[1] && '\\' == path[2]) return true;
+  if ('\\\\' == path.substring(0, 2)) return true; // Microsoft Azure absolute path
+};
+
+/**
+ * Flatten the given `arr`.
+ *
+ * @param {Array} arr
+ * @return {Array}
+ * @api private
+ */
+
+exports.flatten = function(arr, ret){
+  ret = ret || [];
+  var len = arr.length;
+  for (var i = 0; i < len; ++i) {
+    if (Array.isArray(arr[i])) {
+      exports.flatten(arr[i], ret);
+    } else {
+      ret.push(arr[i]);
+    }
+  }
+  return ret;
+};
+
+/**
+ * Normalize the given `type`, for example "html" becomes "text/html".
+ *
+ * @param {String} type
+ * @return {Object}
+ * @api private
+ */
+
+exports.normalizeType = function(type){
+  return ~type.indexOf('/')
+    ? acceptParams(type)
+    : { value: mime.lookup(type), params: {} };
+};
+
+/**
+ * Normalize `types`, for example "html" becomes "text/html".
+ *
+ * @param {Array} types
+ * @return {Array}
+ * @api private
+ */
+
+exports.normalizeTypes = function(types){
+  var ret = [];
+
+  for (var i = 0; i < types.length; ++i) {
+    ret.push(exports.normalizeType(types[i]));
+  }
+
+  return ret;
+};
+
+/**
+ * Generate Content-Disposition header appropriate for the filename.
+ * non-ascii filenames are urlencoded and a filename* parameter is added
+ *
+ * @param {String} filename
+ * @return {String}
+ * @api private
+ */
+
+exports.contentDisposition = function(filename){
+  var ret = 'attachment';
+  if (filename) {
+    filename = basename(filename);
+    // if filename contains non-ascii characters, add a utf-8 version ala RFC 5987
+    ret = /[^\040-\176]/.test(filename)
+      ? 'attachment; filename="' + encodeURI(filename) + '"; filename*=UTF-8\'\'' + encodeURI(filename)
+      : 'attachment; filename="' + filename + '"';
+  }
+
+  return ret;
+};
+
+/**
+ * Parse accept params `str` returning an
+ * object with `.value`, `.quality` and `.params`.
+ * also includes `.originalIndex` for stable sorting
+ *
+ * @param {String} str
+ * @return {Object}
+ * @api private
+ */
+
+function acceptParams(str, index) {
+  var parts = str.split(/ *; */);
+  var ret = { value: parts[0], quality: 1, params: {}, originalIndex: index };
+
+  for (var i = 1; i < parts.length; ++i) {
+    var pms = parts[i].split(/ *= */);
+    if ('q' == pms[0]) {
+      ret.quality = parseFloat(pms[1]);
+    } else {
+      ret.params[pms[0]] = pms[1];
+    }
+  }
+
+  return ret;
+}
+
+/**
+ * Compile "etag" value to function.
+ *
+ * @param  {Boolean|String|Function} val
+ * @return {Function}
+ * @api private
+ */
+
+exports.compileETag = function(val) {
+  var fn;
+
+  if (typeof val === 'function') {
+    return val;
+  }
+
+  switch (val) {
+    case true:
+      fn = exports.wetag;
+      break;
+    case false:
+      break;
+    case 'strong':
+      fn = exports.etag;
+      break;
+    case 'weak':
+      fn = exports.wetag;
+      break;
+    default:
+      throw new TypeError('unknown value for etag function: ' + val);
+  }
+
+  return fn;
+}
+
+/**
+ * Compile "proxy trust" value to function.
+ *
+ * @param  {Boolean|String|Number|Array|Function} val
+ * @return {Function}
+ * @api private
+ */
+
+exports.compileTrust = function(val) {
+  if (typeof val === 'function') return val;
+
+  if (val === true) {
+    // Support plain true/false
+    return function(){ return true };
+  }
+
+  if (typeof val === 'number') {
+    // Support trusting hop count
+    return function(a, i){ return i < val };
+  }
+
+  if (typeof val === 'string') {
+    // Support comma-separated values
+    val = val.split(/ *, */);
+  }
+
+  return proxyaddr.compile(val || []);
+}
+
+/**
+ * Set the charset in a given Content-Type string.
+ *
+ * @param {String} type
+ * @param {String} charset
+ * @return {String}
+ * @api private
+ */
+
+exports.setCharset = function(type, charset){
+  if (!type || !charset) return type;
+
+  var exists = charsetRegExp.test(type);
+
+  // removing existing charset
+  if (exists) {
+    var parts = type.split(';');
+
+    for (var i = 1; i < parts.length; i++) {
+      if (charsetRegExp.test(';' + parts[i])) {
+        parts.splice(i, 1);
+        break;
+      }
+    }
+
+    type = parts.join(';');
+  }
+
+  return type + '; charset=' + charset;
+};