fix: should autofix socket timeout by request.timeout (#300)

eggjs/egg#3140

lib/urllib.js

@@ -939,6 +939,15 @@ function requestWithCallback(url, args, callback) {
       socket = socket.socket;
     }
 
+    var orginalSocketTimeout = getSocketTimeout(socket);
+    if (orginalSocketTimeout && orginalSocketTimeout < responseTimeout) {
+      // make sure socket live longer than the response timer
+      var socketTimeout = responseTimeout + 500;
+      debug('Request#%d socket.timeout(%s) < responseTimeout(%s), reset socket timeout to %s',
+        reqId, orginalSocketTimeout, responseTimeout, socketTimeout);
+      socket.setTimeout(socketTimeout);
+    }
+
     socketHandledRequests = socket[SOCKET_REQUEST_COUNT] = (socket[SOCKET_REQUEST_COUNT] || 0) + 1;
     if (socket[SOCKET_RESPONSE_COUNT]) {
       socketHandledResponses = socket[SOCKET_RESPONSE_COUNT];
@@ -1131,3 +1140,9 @@ function addLongStackTrace(err, req) {
     err.stack += LONG_STACK_DELIMITER + callSiteStack.substr(index + 1);
   }
 }
+
+// node 8 don't has timeout attribute on socket
+// https://github.com/nodejs/node/pull/21204/files#diff-e6ef024c3775d787c38487a6309e491dR408
+function getSocketTimeout(socket) {
+  return socket.timeout || socket._idleTimeout;
+}

test/request-timeout.test.js

@@ -0,0 +1,42 @@
+'use strict';
+
+var assert = require('assert');
+var Agent = require('agentkeepalive');
+var urllib = require('..');
+var server = require('./fixtures/server');
+
+describe('test/request-timeout.test.js', function() {
+  var host = 'http://127.0.0.1:';
+  var port;
+
+  before(function(done) {
+    server.listen(0, function() {
+      port = server.address().port;
+      host += port;
+      done();
+    });
+  });
+
+  after(function(done) {
+    setTimeout(function() {
+      server.close();
+      done();
+    }, 1000);
+  });
+
+  it('should work on request timeout bigger than agent timeout', function(done) {
+    var agent = new Agent({
+      timeout: 1000,
+    });
+    var url = host + '/response_timeout_10s';
+    urllib.request(url, {
+      timeout: 1500,
+      agent: agent,
+    }, function(err) {
+      assert(err);
+      assert(err.name === 'ResponseTimeoutError');
+      assert(err.message.indexOf('Response timeout for 1500ms') === 0);
+      done();
+    });
+  });
+});