msal-logging-js.md

title	Logging errors and exceptions in MSAL.js
description	Learn how to log errors and exceptions in MSAL.js
author	Dickson-Mwendia
manager	dougeby
ms.author	dmwendia
ms.custom
ms.date	12/19/2023
ms.reviewer	jmprieur
ms.service	identity-platform
ms.topic	concept-article

Logging in MSAL.js

[!INCLUDE MSAL logging introduction]

Configure logging in MSAL.js

Enable logging in MSAL.js (JavaScript) by passing a loggerOptions object during the configuration for creating a PublicClientApplication instance. The only required config parameter is the client ID of the application. Everything else is optional, but may be required depending on your tenant and application model.

The loggerOptions object has the following properties:

• loggerCallback: a Callback function that can be provided by the developer to handle the logging of MSAL statements in a custom manner. Implement the loggerCallback function depending on how you want to redirect logs. The loggerCallback function has the following format (level: LogLevel, message: string, containsPii: boolean): void
  • The supported log levels are: Error, Warning, Info, and Verbose. The default is Info.
• piiLoggingEnabled (optional): if set to true, logs personal and organizational data. By default this is false so that your application doesn't log personal data. Personal data logs are never written to default outputs like Console, Logcat, or NSLog.

import msal from "@azure/msal-browser"

const msalConfig = {
    auth: {
        clientId: "enter_client_id_here",
        authority: "https://login.microsoftonline.com/common",
        knownAuthorities: [],
        cloudDiscoveryMetadata: "",
        redirectUri: "enter_redirect_uri_here",
        postLogoutRedirectUri: "enter_postlogout_uri_here",
        navigateToLoginRequestUrl: true,
        clientCapabilities: ["CP1"]
    },
    cache: {
        cacheLocation: "sessionStorage",
        storeAuthStateInCookie: false,
        secureCookies: false
    },
    system: {
        loggerOptions: {
            logLevel: msal.LogLevel.Verbose,
            loggerCallback: (level, message, containsPii) => {
                if (containsPii) {
                    return;
                }
                switch (level) {
                    case msal.LogLevel.Error:
                        console.error(message);
                        return;
                    case msal.LogLevel.Info:
                        console.info(message);
                        return;
                    case msal.LogLevel.Verbose:
                        console.debug(message);
                        return;
                    case msal.LogLevel.Warning:
                        console.warn(message);
                        return;
                }
            },
            piiLoggingEnabled: false
        },
    },
};

Next steps

For more code samples, refer to Microsoft identity platform code samples.