Several fixes to http client

  - Only attempts to "render" data on first request (not redirects)
  - Allows setting of "redirects" via the data variable
  - Fixed Host header predecence issue
  - Only setting Content-Length / Content-Type when not previously set
  - Passing response object on errors

lib/express/http.js

@@ -21,37 +21,41 @@ var http = require('http'),
  * @api private
  */
 
-function request(method, url, data, headers, callback, redirects) {
+function request(method, url, data, headers, callback, redirects, first) {
   var buf = '',
-      redirects = redirects || 3,
+      redirects = typeof redirects !== 'number' ? 3 : redirects,
       url = parse(url),
       path = url.pathname || '/',
       search = url.search || '',
       hash = url.hash || '',
       port = url.port || 80,
-      headers = { host: url.hostname }.merge(headers || {}),
+      headers = (headers || {}).merge({ Host: url.hostname }),
       client = http.createClient(port, url.hostname)
-  if (headers.redirect)
-    redirects = headers.redirect,
-    delete headers.redirect
-  if (data) {
-    data = queryString.stringify(data)
+  if (typeof data === 'object' && 'redirects' in data)
+    redirects = data.redirects,
+    delete data.redirects
+  if (first && data) {
+    if (typeof data !== 'string')
+      data = queryString.stringify(data)
     if (method === 'GET')
       search += (search ? '&' : '?') + data
-    else
-      headers['Content-Length'] = data.length,
-      headers['Content-Type'] = 'application/x-www-form-urlencoded'
+    else {
+      if (!headers['Content-Length'])
+        headers['Content-Length'] = data.length
+      if (!headers['Content-Type'])
+        headers['Content-Type'] = 'application/x-www-form-urlencoded'
+    }
   }
   var req = client.request(method, path + search + hash, headers)
   if (data && method !== 'GET') req.write(data)
   req.addListener('response', function(res){
-    if (req.statusCode < 200 || req.statusCode >= 400)
-      callback(new Error('request failed with status ' + res.statusCode + ' "' + http.STATUS_CODES[res.statusCode] + '"'))
+    if (res.statusCode < 200 || res.statusCode >= 400)
+      callback(new Error('request failed with status ' + res.statusCode + ' "' + http.STATUS_CODES[res.statusCode] + '"'), '', res)
     else if (res.statusCode >= 300 && res.statusCode < 400)
-      if (--redirects)
-        request(method, res.headers.location, data, headers, callback, redirects)
+      if (redirects--)
+        request(method, res.headers.location, data, headers, callback, redirects, false)
       else
-        callback(new Error('maximum number of redirects reached'))
+        callback(new Error('maximum number of redirects reached'), '', res)
     else {
       res.setBodyEncoding('utf8')
       res
@@ -72,20 +76,39 @@ function request(method, url, data, headers, callback, redirects) {
 
 function client(method) {
   return function() {
-    var headers, data,
+    var redirects,
         args = Array.prototype.slice.call(arguments),
         url = args.shift(),
         callback = args.pop(),
         data = args.shift(),
         headers = args.shift()
     if (typeof callback !== 'function')
       throw new TypeError('http client requires a callback function')
-    return request(method.toUpperCase(), url, data, headers, callback)
+    return request(method.toUpperCase(), url, data, headers, callback, redirects, true)
   }
 }
 
 // --- Public API
 
+/**
+ * Examples:
+ *
+ *   var http = require('express/http')
+ *
+ *   http.get('http://google.com/search', { q: 'foobar' }, function(err, body, response){
+ *     if (!err) sys.puts(body)
+ *   })
+ *
+ *   http.get('http://google.com/search?lang=en', { q: 'foobar' }, function(){
+ *     // ...
+ *   })
+ *
+ *   http.post('http://localhost:8000', '<user>tj</user>', { 'Content-Type': 'text/xml' }, function(err, body){
+ *     // ...
+ *   })
+ *
+ */
+
 exports.get  = exports.view    = client('get')
 exports.post = exports.create  = client('post')
 exports.put  = exports.update  = client('put')