statsd/test/graphite_pickle_tests.js

var fs           = require('fs'),
    net          = require('net'),
    temp         = require('temp'),
    cp           = require('child_process'),
    util          = require('util'),
    urlparse     = require('url').parse,
    _            = require('underscore'),
    dgram        = require('dgram'),
    qsparse      = require('querystring').parse,
    http         = require('http');

var spawn = cp.spawn;

var writeconfig = function(text,worker,cb,obj){
  temp.open({suffix: '-statsdconf.js'}, function(err, info) {
    if (err) throw err;
    fs.writeSync(info.fd, text);
    fs.close(info.fd, function(err) {
      if (err) throw err;
      worker(info.path,cb,obj);
    });
  });
};

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){
  // We have binary data arriving over the wire. Avoid strings.
  var received = new Buffer(0);
  var in_flight = 0;
  var timed_out = false;
  var collector = function(req,res){
    in_flight += 1;
    req.on('data',function(data){ received = Buffer.concat([received,data]); });
    req.on('end',function(){
      in_flight -= 1;
      if((in_flight < 1) && timed_out){
          server.removeListener('request',collector);
          cb(received);
      }
    });
  };

  setTimeout(function (){
    timed_out = true;
    if((in_flight < 1)) {
      server.removeListener('connection',collector);
      cb(received);
    }
  },timeout);

  server.on('connection',collector);
};

// A python script that converts from the graphite pickle-based 
// wire protocol into JSON written to stdout.
var script =
  "import sys\n" +
  "import pickle\n" +
  "import struct\n" +
  "import json\n" +
  "payload = open(sys.argv[1], 'rb').read()\n" +
  "pack_format = '!L'\n" +
  "header_length = struct.calcsize(pack_format)\n" +
  "payload_length, = struct.unpack(pack_format, payload[:header_length])\n" +
  "batch_length = header_length + payload_length\n" +
  "metrics = pickle.loads(payload[header_length:batch_length])\n" +
  "print(json.dumps(metrics))\n";

// Write our binary payload and unpickling script to disk
// then process the unserialized results.
var unpickle = function(payload, cb) {
  temp.open({suffix: '-payload.pickle'}, function(err, payload_info) {
    if (err) throw err;

    // the header may contain null characters. explicit length is necessary.
    var len = fs.writeSync(payload_info.fd, payload, 0, payload.length);
    fs.close(payload_info.fd, function(err) {
      if (err) throw err;

      temp.open({suffix:'-unpickle.py'}, function(err, unpickle_info) {
        if (err) throw err;

        fs.writeSync(unpickle_info.fd, script);
        fs.close(unpickle_info.fd, function(err) {
          if (err) throw err;

          var cmd = 'python ' + unpickle_info.path + ' ' + payload_info.path;
          var python = cp.exec(cmd, function(err, stdout, stderr) {
            if (err) throw err;
            var metrics = JSON.parse(stdout);
            // Transform the output into the same list of dictionaries 
            // used by the other graphite_* tests so our tests look 
            // the same.
            var hashes = _.map(metrics, function(m) {
              var data = {};
              data[m[0]] = m[1][1];
              return data;
            });
            cb(hashes);
          });
        });
      });
    });
  });
};

module.exports = {
  setUp: function (callback) {
    this.testport = 31337;
    this.myflush = 200;
    var configfile = "{graphService: \"graphite\"\n\
               ,  batch: 200 \n\
               ,  flushInterval: " + this.myflush + " \n\
               ,  percentThreshold: 90\n\
               ,  histogram: [ { metric: \"a_test_value\", bins: [1000] } ]\n\
               ,  port: 8125\n\
               ,  dumpMessages: false \n\
               ,  debug: false\n\
               ,  graphite: { legacyNamespace: false }\n\
               ,  graphitePicklePort: " + this.testport + "\n\
               ,  graphiteHost: \"127.0.0.1\"\n\
               ,  graphiteProtocol: \"pickle\"}";

    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();
    }
  },

  timers_are_valid: function (test) {
    test.expect(6);

    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(payload){
          test.ok(payload.length > 0,'should receive some data');
          unpickle(payload, function(hashes) {
            var numstat_test = function(post){
              var mykey = 'stats.statsd.numStats';
              return _.include(_.keys(post),mykey) && (post[mykey] == 5);
            };
            test.ok(_.any(hashes,numstat_test), 'stats.statsd.numStats should be 5');

            var testtimervalue_test = function(post){
              var mykey = 'stats.timers.a_test_value.mean_90';
              return _.include(_.keys(post),mykey) && (post[mykey] == testvalue);
            };
            var testtimerhistogramvalue_test = function(post){
              var mykey = 'stats.timers.a_test_value.histogram.bin_1000';
              return _.include(_.keys(post),mykey) && (post[mykey] == 1);
            };
            test.ok(_.any(hashes,testtimerhistogramvalue_test), 'stats.timers.a_test_value.histogram.bin_1000 should be ' + 1);
            test.ok(_.any(hashes,testtimervalue_test), 'stats.timers.a_test_value.mean_90 should be ' + testvalue);

            var count_test = function(post, metric){
              var mykey = 'stats.timers.a_test_value.' + metric;
              return _.first(_.filter(_.pluck(post, mykey), function (e) { return e; }));
            };
            test.equals(count_test(hashes, 'count_ps'), 5, 'count_ps should be 5');
            test.equals(count_test(hashes, 'count'), 1, 'count should be 1');

            test.done();
          });
        });
      });
    });
  }
};