Limit the max stack length

plugins/errors.js

@@ -252,6 +252,11 @@ if (!Array.isArray) {
 		"BOOMR_plugins_errors_wrap"
 	];
 
+	/**
+	 * Maximum size, in characters, of stack to capture
+	 */
+	var MAX_STACK_SIZE = 5000;
+
 	/**
 	 * BoomerangError object
 	 *
@@ -398,6 +403,10 @@ if (!Array.isArray) {
 
 		// parse the stack
 		if (error.stack) {
+			if (error.stack.length > MAX_STACK_SIZE) {
+				error.stack = error.stack.substr(0, MAX_STACK_SIZE);
+			}
+
 			frames = ErrorStackParser.parse(error);
 			if (frames && frames.length) {
 				if (error.generatedStack) {

tests/page-templates/14-errors/21-max-stack.html

@@ -0,0 +1,22 @@
+<%= header %>
+<%= boomerangScript %>
+<script src="21-max-stack.js" type="text/javascript"></script>
+<script>
+BOOMR_test.init({
+	testAfterOnBeacon: true,
+	Errors: {
+		enabled: true
+	}
+});
+
+var stack = "";
+for (var i = 0; i < 10000; i++) {
+	stack += "a";
+}
+
+BOOMR.plugins.Errors.send({
+	stack: stack,
+	message: "a is not defined"
+});
+</script>
+<%= footer %>

tests/page-templates/14-errors/21-max-stack.js

@@ -0,0 +1,30 @@
+/*eslint-env mocha*/
+/*global BOOMR_test,assert*/
+
+describe("e2e/14-errors/21-max-stack", function() {
+	var tf = BOOMR.plugins.TestFramework;
+	var t = BOOMR_test;
+	var C = BOOMR.utils.Compression;
+
+	it("Should have sent a single beacon", function(done) {
+		t.validateBeaconWasSent(done);
+	});
+
+	it("Should have put the err on the beacon", function() {
+		var b = tf.lastBeacon();
+		assert.isDefined(b.err);
+	});
+
+	it("Should have had 1 error", function() {
+		var b = tf.lastBeacon();
+		assert.equal(C.jsUrlDecompress(b.err).length, 1);
+	});
+
+	it("Should have had a stack with a max length of around 5000 chars", function() {
+		var b = tf.lastBeacon();
+		var err = BOOMR.plugins.Errors.decompressErrors(C.jsUrlDecompress(b.err))[0];
+
+		// allow for some wiggle room in message length, but close to 5000
+		assert.closeTo(err.stack.length, "a is not defined".length + 5000, 10, "stack: " + err.stack);
+	});
+});