feat: implement trace option like mysql client (#290)

README.md

@@ -164,6 +164,7 @@ httpclient.request('http://nodejs.org', function (err, body) {
     - ***proxy*** String | Object - proxy agent uri or options, default is `null`.
     - ***lookup*** Function - Custom DNS lookup function, default is `dns.lookup`. Require node >= 4.0.0(for http protocol) and node >=8(for https protocol)
     - ***checkAddress*** Function: optional, check request address to protect from SSRF and similar attacks. It receive tow arguments(`ip` and `family`) and should return true or false to identified the address is legal or not. It rely on `lookup` and have the same version requirement.
+    - ***trace*** Boolean - Enable capture stack include call site of library entrance, default is `false`.
 - ***callback(err, data, res)*** Function - Optional callback.
     - **err** Error - Would be `null` if no error accured.
     - **data** Buffer | Object - The data responsed. Would be a Buffer if `dataType` is set to `text` or an JSON parsed into Object if it's set to `json`.
@@ -361,6 +362,21 @@ https_proxy=https://localhost:8008
 $ http_proxy=http://localhost:8008 node index.js
 ```
 
+### Trace
+If set trace true, error stack will contains full call stack, like
+```
+Error: connect ECONNREFUSED 127.0.0.1:11
+    at TCPConnectWrap.afterConnect [as oncomplete] (net.js:1113:14)
+    --------------------
+    at ~/workspace/urllib/lib/urllib.js:150:13
+    at new Promise (<anonymous>)
+    at Object.request (~/workspace/urllib/lib/urllib.js:149:10)
+    at Context.<anonymous> (~/workspace/urllib/test/urllib_promise.test.js:49:19)
+    ....
+```
+
+When open the trace, urllib may have poor perfomance, please consider carefully.
+
 ## TODO
 
 * [ ] Support component

benchmark/trace.js

@@ -0,0 +1,52 @@
+'use strict';
+
+var Benchmark = require('benchmark');
+var http = require('http');
+var urllib = require('../');
+var suite = new Benchmark.Suite();
+var agent = new http.Agent({
+  keepAlive: true,
+  keepAliveMsecs: 5000,
+  maxSockets: 100,
+  timeout: 5000,
+});
+
+// start your nginx listen 8080 with hello,world
+
+function request(trace, deferred) {
+  urllib.request('http://127.0.0.1:8080', {
+    timeout: 20000,
+    trace: trace,
+    agent: agent,
+  }).then(function() {
+    deferred.resolve();
+  });
+}
+
+suite
+  .add('warm up agent', {
+    defer: true,
+    fn: function(deferred) {
+      request(false, deferred);
+    }
+  })
+  .add('request with no trace', {
+    defer: true,
+    fn: function(deferred) {
+      request(false, deferred);
+    }
+  })
+  .add('request with trace', {
+    defer: true,
+    fn: function(deferred) {
+      request(true, deferred);
+    }
+  })
+  .on('cycle', function(event) {
+    console.log(String(event.target));
+  })
+  .on('complete', function() {
+    console.log('Fastest is ' + this.filter('fastest').map('name'));
+  })
+  // run async
+  .run({ 'async': true });

lib/urllib.js

@@ -33,6 +33,8 @@ exports.agent.maxSockets = 1000;
 exports.httpsAgent = new https.Agent();
 exports.httpsAgent.maxSockets = 1000;
 
+var LONG_STACK_DELIMITER = '\n    --------------------\n';
+
 /**
  * The default request timeout(in milliseconds).
  * @type {Number}
@@ -183,7 +185,7 @@ exports.requestThunk = function requestThunk(url, args) {
   };
 };
 
-exports.requestWithCallback = function requestWithCallback(url, args, callback) {
+function requestWithCallback(url, args, callback) {
   // requestWithCallback(url, callback)
   if (!url || (typeof url !== 'string' && typeof url !== 'object')) {
     var msg = util.format('expect request url to be a string or a http request options, but got %j', url);
@@ -490,6 +492,7 @@ exports.requestWithCallback = function requestWithCallback(url, args, callback)
       err.status = statusCode;
       err.headers = headers;
       err.res = response;
+      addLongStackTrace(err, req);
     }
 
     // only support agentkeepalive module for now
@@ -862,6 +865,10 @@ exports.requestWithCallback = function requestWithCallback(url, args, callback)
   // request headers checker will throw error
   try {
     req = httplib.request(options, onResponse);
+    if (args.trace) {
+      req._callSite = {};
+      Error.captureStackTrace(req._callSite, requestWithCallback);
+    }
   } catch (err) {
     return done(err);
   }
@@ -989,7 +996,9 @@ exports.requestWithCallback = function requestWithCallback(url, args, callback)
 
   req.requestId = reqId;
   return req;
-};
+}
+
+exports.requestWithCallback = requestWithCallback;
 
 var JSONCtlCharsMap = {
   '"': '\\"',       // \u0022
@@ -1080,3 +1089,21 @@ function parseContentType(str) {
     return { parameters: {} };
   }
 }
+
+function addLongStackTrace(err, req) {
+  if (!req) {
+    return;
+  }
+  var callSiteStack = req._callSite && req._callSite.stack;
+  if (!callSiteStack || typeof callSiteStack !== 'string') {
+    return;
+  }
+  if (err._longStack) {
+    return;
+  }
+  var index = callSiteStack.indexOf('\n');
+  if (index !== -1) {
+    err._longStack = true;
+    err.stack += LONG_STACK_DELIMITER + callSiteStack.substr(index + 1);
+  }
+}

package.json

@@ -48,6 +48,7 @@
   "devDependencies": {
     "agentkeepalive": "^3.4.0",
     "autod": "*",
+    "benchmark": "^2.1.4",
     "bluebird": "*",
     "busboy": "^0.2.14",
     "co": "*",

test/urllib_promise.test.js

@@ -50,14 +50,16 @@ describe('test/urllib_promise.test.js', function () {
       data: {
         q: 'foo'
       },
-      timeout: 20000
+      timeout: 20000,
+      trace: true
     })
     .then(function () {
       throw new Error('should not run this');
     }).catch(function (err) {
       assert(err);
       assert(err.code === 'ECONNREFUSED');
       assert(err.status === -1);
+      assert(err.stack.indexOf('--------------------') > 0);
       assert.deepEqual(err.headers, {});
       assert.deepEqual(Object.keys(err.res), [
         'status', 'statusCode', 'headers', 'size', 'aborted', 'rt',
@@ -66,4 +68,30 @@ describe('test/urllib_promise.test.js', function () {
       ]);
     });
   });
+
+  describe('disable trace',function () {
+    it('should not with long stack trace', function () {
+      return urllib.request('http://127.0.0.1:11', {
+        data: {
+          q: 'foo'
+        },
+        timeout: 20000,
+        trace: false
+      })
+        .then(function () {
+          throw new Error('should not run this');
+        }).catch(function (err) {
+          assert(err);
+          assert(err.code === 'ECONNREFUSED');
+          assert(err.status === -1);
+          assert(err.stack.indexOf('--------------------') < 0);
+          assert.deepEqual(err.headers, {});
+          assert.deepEqual(Object.keys(err.res), [
+            'status', 'statusCode', 'headers', 'size', 'aborted', 'rt',
+            'keepAliveSocket', 'data', 'requestUrls', 'timing', 'remoteAddress', 'remotePort',
+            'socketHandledRequests', 'socketHandledResponses',
+          ]);
+        });
+    });
+  });
 });