Client-side JavaScript error reporting library, compatible with ancient browsers.

error-reporter.js

// JavaScript error reporting library.
// Copyright (c) Mahmoud Al-Qudsi, NeoSmart Technologies. All rights reserved.
// Licensed under the MIT License. This copyright notice should be preserved.

function addScript(url) {
    document.write("<script type='text/javascript' src='" + url + "'><\/script>");
}

if (typeof (JSON) === "undefined") {
    addScript("/EasyRE/lib/polyfill/json3/json3.min.js");
}

function getStack() {
    var stack = "";
    for (var func = arguments.callee.caller, i = 0;
        func && func.arguments !== undefined && i <= 10;
        ++i, func = func.caller)
    {
        var args = "(";
        for (var a = 0; a < func.arguments.length; ++a) {
            if (typeof (func.arguments[a]) === "string") {
                args += '`' + func.arguments[a] + '`';
            } else {
                args += func.arguments[a].toString();
            }
            if (a != func.arguments.length - 1) {
                args += ", ";
            }
        }
        args += ")";
        if (func.name !== undefined && func.name.length > 0) {
            stack += ("* " + func.name + args);
        } else if (func.$name !== undefined && func.$name.length > 0) {
            stack += ("* " + func.$name + args);
        } else {
            var matches = func.toString().match(/function\s*([^(\s]*)/)
            if (matches != null && matches.length > 0) {
                if (matches[1].length > 0) {
                    stack += ("* " + matches[1] + args);
                } else {
                    stack += ("* anonymous" + args);
                }
            } else {
                stack += ("* unknown function" + args);
            }
        }
        stack += "\n";
    }

    return stack;
}

function reportError(error, callback) {
    // Wrap everything in a try block to prevent recursive invocation in case of any errors here.
    try {
        if (typeof (callback) !== "function" || callback == null) {
            callback = window.loadNoJs ? loadNoJs : function () { };
        }
        if (Object.defineProperty === undefined) {
            // This browser is too old, and without Object.defineProperty our script will fail to load entirely,
            // meaning the client will fall back to HTML-only mode.
            callback();
            return;
        }
        if (error.colno !== undefined && error.error !== undefined) {
            // This is an ErrorEvent, not an Error
            error = error.error;
        }

        if (typeof (error) === "undefined") {
            error = {
                filename: "",
                line: 0,
                colno: 0,
                message: "undefined",
                stack: ""
            };
        } else if (typeof (error) !== "object") {
            error = {
                filename: "",
                line: 0,
                colno: 0,
                message: error.toString(),
                stack: ""
            }
        } else if (error.error !== undefined) {
            // We do have an error object, but browser does not support error.stack
            error.stack = getStack();
        } else if (error.error === undefined
            && ((error.srcElement !== undefined && error.srcElement !== window)
                // Firefox 24 does not have srcElement but has explicitOriginalTarget/originalTarget/target
                || (error.explicitOriginalTarget && error.explicitOriginalTarget != window))) {
            // error.error isn't defined, so this is probably an intercepted element error
            var element = error.srcElement || error.target;

            if (element.outerHTML && element.outerHTML.match(/bat.bing.com|googlead|googletagmanager.com|analytics.js|js.stripe.com/)) {
                // We don't need to report these
                return;
            }

            error = {
                filename: "",
                lineno: 0,
                colno: 0,
                message: "Error loading element: " + element.outerHTML,
                stack: ""
            };
        }

        if (error.message && error.message.match(/Blocked a frame/)) {
            // We can't do anything about this and it isn't an error
            return;
        }

        // Match against the likes of moz-extension:// and chrome-extension://
        if (error.stack.match(/extension:\/\//)) {
            // This error was caused by an extension on the user's PC and isn't our problem
            return;
        }

        var xhr = new XMLHttpRequest();
        xhr.open("POST", "/EasyRE/Payment/ReportError", true);
        xhr.setRequestHeader("RequestVerificationToken", "CfDJ8LuzKTdNvaZEjvBiklUVtA9GfPd9AqJowggwCa8dalb2eP-oajV1IfFmY6AaMcBWC3ZlyEZfiuPfiIeBx9Kt65Dc81JKAmNHliBFMYkNHDV6WYMjRGbTSBIQoDWKL2_tkZuZxHaUY89PbBcTYyoXX-DCzF7YIsnfxJbQx2UzcY3g6Y_W33jKWXpVOAxJSQ-ZVw");
        xhr.setRequestHeader("Content-Type", "application/json");
        xhr.onreadystatechange = function () {
            if (xhr.readyState == 4 &&
                ((xhr.status >= 200 && xhr.status < 300) || (xhr.status >= 400))) {
                callback();
            }
        }
        xhr.send(JSON.stringify({
            "url": window.location.toString(),
            "invoice": "329D6DFAA450F49D",
            "error": {
                "browser": window.navigator.userAgent,
                "file": error.filename,
                "line": error.lineno,
                "column": error.colno,
                "message": error.message,
                "stacktrace": error.stack
            }
        }));
    }
    catch (ex) {
        if (window.console && window.console.error) {
            console.error("Error reporting errors!");
            console.error(ex);
        }
        if (callback && typeof (callback) === "function") {
            callback();
        }
    }
}

var interceptAll = false;
if (window.addEventListener !== undefined) {
    var mustUseObject = false;
    try {
        window.addEventListener("test", null, Object.defineProperty({}, "capture", { get: function () { mustUseObject = true; } }));
    } catch (_) {
    }

    window.addEventListener("error", function (e) {
        reportError(e, loadNoJs);
    }, mustUseObject ? { "passive": true, "capture": interceptAll } : true);
}
else if (window.attachEvent !== undefined) {
    window.attachEvent("onerror", reportError);
}
else if (window.onerror !== undefined) {
    window.onerror = function (msg, source, lineno, colno, error) {
        reportError({
            filename: source,
            lineno: lineno,
            colno: colno,
            message: msg,
            error: error
        }, loadNoJs);
    }
}