Rollbar

Getting Started

Copy-paste the following code into the <head> of every page you want to track. It should be as high as possible, before any other <script> tags.

<script>
var _rollbarParams = {"server.environment": "production"};
_rollbarParams["notifier.snippet_version"] = "2"; var _rollbar=["YOUR_PROJECT_ACCESS_TOKEN", _rollbarParams]; var _ratchet=_rollbar;
(function(w,d){w.onerror=function(e,u,l){_rollbar.push({_t:'uncaught',e:e,u:u,l:l});};var i=function(){var s=d.createElement("script");var 
f=d.getElementsByTagName("script")[0];s.src="//d37gvrvc0wt4s1.cloudfront.net/js/1/rollbar.min.js";s.async=!0;
f.parentNode.insertBefore(s,f);};if(w.addEventListener){w.addEventListener("load",i,!1);}else{w.attachEvent("onload",i);}})(window,document);
</script>

If you're running Rollbar on an environment besides production, change the server.environment value to something else (e.g. "staging").

See below for additional configuration options.

Test your installation

Navigate your browser to a page that has the above code installed
Type the following code into the address bar (not the console) and press enter: javascript:testing_rollbar_123();

As long as you don't happen to have a function by that name, this will cause an uncaught error that will be reported to Rollbar. It should appear in the dashboard within a few seconds.

Generic logging

In addition to catching top-level errors, you can use _rollbar.push to send custom log messages. It is fully-asynchronous and safe to call anywhere in your code after the <script> tag above.

_rollbar.push accepts arguments of any of the following forms:

An Error instance (i.e. for reporting a caught exception):
```
for (var i = 0; i < someVar; ++i) {
  var elem = i;
  var callback = function(err) {
    if (err !== null) {
      console.log('An error occurred while reporting elem ' + elem + ' to Rollbar, ' + err);
    }
  }
  try {
    doSomething();
  } catch (e) {
    _rollbar.push(e, callback);
  }
}
```
A plain string:
```
_rollbar.push("Some log message");
```
An object containing a 'msg' property, an optional 'level' property, an optional '_fingerprint' property, and any arbitrary data you want to send (as long as it can be encoded by JSON.stringify()):
```
_rollbar.push({level: 'warning', msg: "Some warning message", point: {x: 5, y: 10}});
```
Note: jQuery objects can not be encoded by JSON.stringify(), so don't pass them as-is.
level is optional and can take any of the following values: 'critical', 'error', 'warning', 'info', 'debug'
_fingerprint is optional; if provided, it will be override the fingerprint used for grouping. Should be a string no longer than 40 characters.

If you want to wrap console.log, try the following:

if (typeof console === 'undefined') {
  console = {log: function() {}};
}
var old_console_log = console.log;
function rollbar_console_log() {
  old_console_log.apply(this, arguments);
  var message = {level: 'info', msg: arguments[0]};
  for (var i = 1; i < arguments.length; i++) {
    message[i] = arguments[i];
  }
  _rollbar.push(message);
}
console.log = rollbar_console_log;

Configuration

The default configuration sets:

the environment name to "production"
the severity level of all uncaught errors to "warning"
a client-side rate-limit of 5 per minute

All of these are configurable via the _rollbarParams object.

checkIgnore: An optional function that will be used to ignore uncaught exceptions based on its return value. The function signature should be: function checkIgnore(errMsg, url, lineNo) { ... } and should return true if the error should be ignored.
Default: null
context: Name of the page context -- i.e. route name, url, etc. Can be used in the Rollbar interface to search for items by context prefix.
itemsPerMinute: Max number of items to report per minute. The limit counts uncaught errors (reported through window.onerror) and any direct calls to _rollbar.push(). This is intended as a sanity check against infinite loops, but if you're using Rollbar heavily for logging, you may want to increase this.
Default: 5
level: The severity level to report javascript errors at. One of "critical", "error", "warning", "info", "debug".
Default: "warning"
person: An object identifying the logged-in user, containing an id (required), and optionally a username and email (all strings). Passing this will allow you to see which users were affected by particular errors, as well as all the errors that a particular user experienced.
server.branch: The name of the branch of the code that is running. Used for linking filenames in stacktraces to GitHub.
Default: master.
server.environment: Environment name, e.g. "production" or "development". Can be an arbitrary string, though to take advantage of the default notifications settings, we recommend using "production" for your production environment.
server.host: The hostname of the machine that rendered the page, e.g. web1.mysite.com. e.g. in Python, use socket.gethostname().

Example

Using all config options:

var _rollbarParams = {
  checkIgnore: function(errMsg, url, lineNo) {
    // don't ignore anything (default)
    return false;
  },
  context: "home#index",
  itemsPerMinute: 60,
  level: "error",
  person: {
    id: 12345,
    username: "johndoe",
    email: "johndoe@example.com"
  },
  "server.branch": "develop",
  "server.environment": "staging",
  "server.host": "web1"
};

Callbacks

You can pass in an optional callback to _rollbar.push(obj, callback) which will be called when the item is reported to the Rollbar servers. If an error occurs, the callback will be evaluated with 1 argument defining the error that occurred.

for (var i = 0; i < someVar; ++i) {
  var elem = i;
  var callback = function(err) {
    if (err !== null) {
      console.log('An error occurred while reporting elem ' + elem + ' to Rollbar, ' + err);
    }
  }
  try {
    doSomething();
  } catch (e) {
    _rollbar.push(e, callback);
  }
}