strong-trace/instrument.js

StrongTrace Node.js Tracer

"use strict";

exports = module.exports = instrument
exports.checkBlacklist = checkBlacklist

var xtend = require("xtend")
var toRe = require("glob-to-regexp")

var requireTx = require("./require_transform")
var Tracer = require("./core_tracer")
var core = require("./wrappers/core/")

var DEFAULT_CONFIG = {
  "instrument": true,

  "trace": true,
  "transactions": true,

  // Core modules
  "wrap_core": true,

  "wrap_timers": true,
  "wrap_process": true,

  "wrap_dns": true,
  "wrap_fs": true,
  "wrap_http": true, // also wraps https
  "wrap_zlib": true,
  // TBD
  //"wrap_crypto": true,
  //"wrap_net": true,
  //"wrap_dgram": true,
  //"wrap_events": true,

  // Third party special-cased modules.
  // "wrap_redis": true,

  // Third party native modules
  // "wrap_native": true,

  "rewrite_returns": true,
  "min_calls": 0, //1,
  "min_nodes": 1, //4,
  "min_length": 0,
  "max_scope_depth": 1000,
  "max_stack_length": 20000,

  "max_links_per_stack": 100,

  "follow_links": true,

  "enable_cca": false,

  "blacklist": []
}


function checkBlacklist(filename) {
  if (process.platform === "win32")
    filename = filename.replace(/\\/g, "/")
  function test(glob) {
    return toRe(glob).test(filename)
  }
  return !(this.blacklist.some(test))
}

function instrument(config) {
  config = xtend(DEFAULT_CONFIG, config)

  // Instantiates the tracer in the global namespace.
  var tracer = new Tracer(config)

  // Has to come after the tracer is instantiated.
  var FunctionTrace = require("./function_trace")

  wrapCore(config, tracer)

  if (config.instrument) {
    requireTx(FunctionTrace(config), checkBlacklist.bind(config))
  }

  return tracer
}

function wrapCore(config, tracer) {
  if (!config.wrap_core) {
    return
  }
  if (config.wrap_timers) {
    core.wrapTimers(tracer)
  }
  if (config.wrap_process) {
    core.wrapProcess(tracer)
  }
  if (config.wrap_http) {
    core.wrapHttp(tracer, "http")
    core.wrapHttp(tracer, "https")
    core.wrapHttpOutgoingMessage(tracer)
  }
  if (config.wrap_fs) {
    core.wrapFs(tracer)
  }
  if (config.wrap_dns) {
    core.wrapDns(tracer)
  }
  if (config.wrap_zlib) {
    core.wrapZlib(tracer)
  }
}