Send 'error' severity by default & document how to set it

README.md

@@ -139,6 +139,19 @@ airbrake.notify(err, function(err, url) {
 By default only the errors from the production environment will get reported,
 so make sure to put `production` in your `NODE_ENV`.
 
+### Severity
+
+[Severity](https://airbrake.io/docs/airbrake-faq/what-is-severity/) allows
+categorizing how severe an error is. By default, it's set to `error`. To
+redefine severity, simply set an error's `severity` property. For example:
+
+```js
+var err = new Error();
+err.severity = 'critical';
+
+airbrake.notify(err);
+```
+
 ### Express integration
 
 The library provides out-of-box integration with the Express framework. It
@@ -200,6 +213,7 @@ each delivered error:
 * **error.class:** (`err.type` string if set, or `'Error'`)
 * **error.message:** (`err.message` string)
 * **error.backtrace:** (`err.stack` as parsed by [stack-trace][])
+* **error.severity:** (`err.severity` defaults to `error`)
 * **request.url:** (`err.url`, see `airbrake.url`);
 * **request.component:** (`err.component` string if set);
 * **request.action:** (`err.action` string if set);

lib/airbrake.js

@@ -1,4 +1,4 @@
-var HTTP_STATUS_CODES = require('http').STATUS_CODES;
+var pkg = require('../package.json');
 
 var fs = require('fs');
 var os = require('os');
@@ -11,7 +11,10 @@ var url = require('url');
 
 var truncator = require('../lib/truncator');
 
-var pkg = require('../package.json');
+
+var HTTP_STATUS_CODES = require('http').STATUS_CODES;
+var DEFAULT_SEVERITY = 'error';
+
 
 function Airbrake() {
   this.key = null;
@@ -317,6 +320,7 @@ Airbrake.prototype.contextJSON = function(err) {
   context.userAgent = err.ua;
   context.component = err.component;
   context.action = err.action;
+  context.severity = err.severity || DEFAULT_SEVERITY;
 
   return context;
 };

test/test-severity.js

@@ -0,0 +1,19 @@
+var common = require('./common');
+var airbrake = require(common.dir.root).createClient(common.projectId, common.key);
+var assert = require('assert');
+
+(function testDefaultSeverity() {
+  var err = new Error();
+  var context = airbrake.contextJSON(err);
+
+  assert.equal(context.severity, 'error');
+}());
+
+(function testCustomSeverity() {
+  var customSeverity = 'critical';
+  var err = new Error();
+  err.severity = customSeverity;
+  var context = airbrake.contextJSON(err);
+
+  assert.equal(context.severity, customSeverity);
+}());