Merge pull request statsd#53 from librato/feature/test_harness

Add basic test framework

README.md

@@ -102,6 +102,12 @@ Installation and Configuration
 
     node stats.js /path/to/config
 
+Tests
+-----
+
+A test framework has been added using node-unit and some custom code to start and manipulate statsd. Please add tests under test/ for any new features or bug fixes encountered. Testing a live server can be tricky, attempts were made to eliminate race conditions but it may be possible to encounter a stuck state. If doing dev work, a `killall node` will kill any stray test servers in the background (don't do this on a production machine!).
+
+Tests can be executd with `./run_tests.sh`.
 
 Inspiration
 -----------

run_tests.sh

@@ -0,0 +1,12 @@
+#!/usr/bin/env node
+try {
+    var reporter = require('nodeunit').reporters.default;
+}
+catch(e) {
+    console.log("Cannot find nodeunit module.");
+    console.log("Make sure to run 'npm install nodeunit'");
+    process.exit();
+}
+
+process.chdir(__dirname);
+reporter.run(['test/']);

stats.js

@@ -131,6 +131,8 @@ config.configFile(process.argv[2], function (config, oldConfig) {
     server.bind(config.port || 8125);
     mgmtServer.listen(config.mgmt_port || 8126);
 
+    sys.log("server is up");
+
     var flushInterval = Number(config.flushInterval || 10000);
 
     flushInt = setInterval(function () {

test/graphite_tests.js

@@ -0,0 +1,227 @@
+var fs           = require('fs'),
+    net          = require('net'),
+    temp         = require('temp'),
+    spawn        = require('child_process').spawn,
+    sys          = require('sys'),
+    urlparse     = require('url').parse,
+    _            = require('underscore'),
+    dgram        = require('dgram'),
+    qsparse      = require('querystring').parse,
+    http         = require('http');
+
+
+var writeconfig = function(text,worker,cb,obj){
+  temp.open({suffix: '-statsdconf.js'}, function(err, info) {
+    if (err) throw err;
+    fs.write(info.fd, text);
+    fs.close(info.fd, function(err) {
+      if (err) throw err;
+      worker(info.path,cb,obj);
+    });
+  });
+}
+
+var array_contents_are_equal = function(first,second){
+  var intlen = _.intersection(first,second).length;
+  var unlen = _.union(first,second).length;
+  return (intlen == unlen) && (intlen == first.length);
+}
+
+var statsd_send = function(data,sock,host,port,cb){
+  send_data = new Buffer(data);
+  sock.send(send_data,0,send_data.length,port,host,function(err,bytes){
+    if (err) {
+      throw err;
+    }
+    cb();
+  });
+}
+
+// keep collecting data until a specified timeout period has elapsed
+// this will let us capture all data chunks so we don't miss one
+var collect_for = function(server,timeout,cb){
+  var received = [];
+  var in_flight = 0;
+  var start_time = new Date().getTime();
+  var collector = function(req,res){
+    in_flight += 1;
+    var body = '';
+    req.on('data',function(data){ body += data; });
+    req.on('end',function(){
+      received = received.concat(body.split("\n"));
+      in_flight -= 1;
+      if((in_flight < 1) && (new Date().getTime() > (start_time + timeout))){
+          server.removeListener('request',collector);
+          cb(received);
+      }
+    });
+  }
+
+  setTimeout(function (){
+    server.removeListener('connection',collector);
+    if((in_flight < 1)){
+      cb(received);
+    }
+  },timeout);
+
+  server.on('connection',collector);
+}
+
+module.exports = {
+  setUp: function (callback) {
+    this.testport = 31337;
+    this.myflush = 200;
+    var configfile = "{graphService: \"graphite\"\n\
+               ,  batch: 200 \n\
+               ,  flushInterval: " + this.myflush + " \n\
+               ,  port: 8125\n\
+               ,  dumpMessages: false \n\
+               ,  debug: false\n\
+               ,  graphitePort: " + this.testport + "\n\
+               ,  graphiteHost: \"127.0.0.1\"}";
+
+    this.acceptor = net.createServer();
+    this.acceptor.listen(this.testport);
+    this.sock = dgram.createSocket('udp4');
+
+    this.server_up = true;
+    this.ok_to_die = false;
+    this.exit_callback_callback = process.exit;
+
+    writeconfig(configfile,function(path,cb,obj){
+      obj.path = path;
+      obj.server = spawn('node',['stats.js', path]);
+      obj.exit_callback = function (code) {
+        obj.server_up = false;
+        if(!obj.ok_to_die){
+          console.log('node server unexpectedly quit with code: ' + code);
+          process.exit(1);
+        }
+        else {
+          obj.exit_callback_callback();
+        }
+      };
+      obj.server.on('exit', obj.exit_callback);
+      obj.server.stderr.on('data', function (data) {
+        console.log('stderr: ' + data.toString().replace(/\n$/,''));
+      });
+      /*
+      obj.server.stdout.on('data', function (data) {
+        console.log('stdout: ' + data.toString().replace(/\n$/,''));
+      });
+      */
+      obj.server.stdout.on('data', function (data) {
+        // wait until server is up before we finish setUp
+        if (data.toString().match(/server is up/)) {
+          cb();
+        }
+      });
+
+    },callback,this);
+  },
+  tearDown: function (callback) {
+    this.sock.close();
+    this.acceptor.close();
+    this.ok_to_die = true;
+    if(this.server_up){
+      this.exit_callback_callback = callback;
+      this.server.kill();
+    } else {
+      callback();
+    }
+  },
+
+  send_well_formed_posts: function (test) {
+    test.expect(2);
+
+    // we should integrate a timeout into this
+    this.acceptor.once('connection',function(c){
+      var body = '';
+      c.on('data',function(d){ body += d; });
+      c.on('end',function(){
+        var rows = body.split("\n");
+        var entries = _.map(rows, function(x) {
+          var chunks = x.split(' ');
+          var data = {};
+          data[chunks[0]] = chunks[1];
+          return data;
+        });
+        test.ok(_.include(_.map(entries,function(x) { return _.keys(x)[0] }),'statsd.numStats'),'graphite output includes numStats');
+        test.equal(_.find(entries, function(x) { return _.keys(x)[0] == 'statsd.numStats' })['statsd.numStats'],0);
+        test.done();
+      });
+    });
+  },
+
+  timers_are_valid: function (test) {
+    test.expect(3);
+
+    var testvalue = 100;
+    var me = this;
+    this.acceptor.once('connection',function(c){
+      statsd_send('a_test_value:' + testvalue + '|ms',me.sock,'127.0.0.1',8125,function(){
+          collect_for(me.acceptor,me.myflush*2,function(strings){
+            test.ok(strings.length > 0,'should receive some data');
+            var hashes = _.map(strings, function(x) {
+              var chunks = x.split(' ');
+              var data = {};
+              data[chunks[0]] = chunks[1];
+              return data;
+            });
+            var numstat_test = function(post){
+              var mykey = 'statsd.numStats';
+              return _.include(_.keys(post),mykey) && (post[mykey] == 1);
+            };
+            test.ok(_.any(hashes,numstat_test), 'statsd.numStats should be 1');
+
+            var testtimervalue_test = function(post){
+              var mykey = 'stats.timers.a_test_value.mean';
+              return _.include(_.keys(post),mykey) && (post[mykey] == testvalue);
+            };
+            test.ok(_.any(hashes,testtimervalue_test), 'stats.timers.a_test_value.mean should be ' + testvalue);
+
+            test.done();
+          });
+      });
+    });
+  },
+
+  counts_are_valid: function (test) {
+    test.expect(4);
+
+    var testvalue = 100;
+    var me = this;
+    this.acceptor.once('connection',function(c){
+      statsd_send('a_test_value:' + testvalue + '|c',me.sock,'127.0.0.1',8125,function(){
+          collect_for(me.acceptor,me.myflush*2,function(strings){
+            test.ok(strings.length > 0,'should receive some data');
+            var hashes = _.map(strings, function(x) {
+              var chunks = x.split(' ');
+              var data = {};
+              data[chunks[0]] = chunks[1];
+              return data;
+            });
+            var numstat_test = function(post){
+              var mykey = 'statsd.numStats';
+              return _.include(_.keys(post),mykey) && (post[mykey] == 1);
+            };
+            test.ok(_.any(hashes,numstat_test), 'statsd.numStats should be 1');
+
+            var testavgvalue_test = function(post){
+              var mykey = 'stats.a_test_value';
+              return _.include(_.keys(post),mykey) && (post[mykey] == (testvalue/(me.myflush / 1000)));
+            };
+            test.ok(_.any(hashes,testavgvalue_test), 'stats.a_test_value should be ' + (testvalue/(me.myflush / 1000)));
+
+            var testcountvalue_test = function(post){
+              var mykey = 'stats_counts.a_test_value';
+              return _.include(_.keys(post),mykey) && (post[mykey] == testvalue);
+            };
+            test.ok(_.any(hashes,testcountvalue_test), 'stats_counts.a_test_value should be ' + testvalue);
+
+            test.done();
+          });
+      });
+    });
+  }
+}