From 9afed44b26ec8c10a02af3ee5a00cded0787da52 Mon Sep 17 00:00:00 2001
From: Douglas Christopher Wilson <doug@somethingdoug.com>
Date: Mon, 25 Aug 2014 00:13:55 -0400
Subject: [PATCH] Use etag to generate ETag header

---
 History.md   |  5 +++++
 lib/send.js  |  7 ++++---
 lib/utils.js | 24 ------------------------
 package.json |  1 +
 4 files changed, 10 insertions(+), 27 deletions(-)

diff --git a/History.md b/History.md
index 5ec9c60..886f51f 100644
--- a/History.md
+++ b/History.md
@@ -1,3 +1,8 @@
+unreleased
+==========
+
+  * Use `etag` to generate `ETag` header
+
 0.8.5 / 2014-09-04
 ==================
 
diff --git a/lib/send.js b/lib/send.js
index 4b4b9f1..3fdb00f 100644
--- a/lib/send.js
+++ b/lib/send.js
@@ -17,6 +17,7 @@ var escapeHtml = require('escape-html')
   , normalize = path.normalize
   , join = path.join
   , utils = require('./utils');
+var etag = require('etag')
 var EventEmitter = require('events').EventEmitter;
 var ms = require('ms');
 var onFinished = require('on-finished')
@@ -718,9 +719,9 @@ SendStream.prototype.setHeader = function setHeader(path, stat){
   if (!res.getHeader('Last-Modified')) res.setHeader('Last-Modified', stat.mtime.toUTCString());
 
   if (this._etag && !res.getHeader('ETag')) {
-    var etag = utils.etag(path, stat);
-    debug('etag %s', etag);
-    res.setHeader('ETag', etag);
+    var val = etag(stat)
+    debug('etag %s', val)
+    res.setHeader('ETag', val)
   }
 };
 
diff --git a/lib/utils.js b/lib/utils.js
index 3a88bf9..ef034b0 100644
--- a/lib/utils.js
+++ b/lib/utils.js
@@ -1,28 +1,4 @@
 
-/**
- * Module dependencies.
- */
-
-var crypto = require('crypto');
-
-/**
- * Return a weak ETag from the given `path` and `stat`.
- *
- * @param {String} path
- * @param {Object} stat
- * @return {String}
- * @api private
- */
-
-exports.etag = function etag(path, stat) {
-  var tag = String(stat.mtime.getTime()) + ':' + String(stat.size) + ':' + path;
-  var str = crypto
-    .createHash('md5')
-    .update(tag, 'utf8')
-    .digest('base64');
-  return 'W/"' + str + '"';
-};
-
 /**
  * decodeURIComponent.
  *
diff --git a/package.json b/package.json
index f15a736..9b9f335 100644
--- a/package.json
+++ b/package.json
@@ -18,6 +18,7 @@
     "depd": "0.4.4",
     "destroy": "1.0.3",
     "escape-html": "1.0.1",
+    "etag": "~1.3.0",
     "fresh": "0.2.2",
     "mime": "1.2.11",
     "ms": "0.6.2",