Start Monitoring Your Node.js Web Application

With Azure Application Insights, you can easily monitor your web application for availability, performance, and usage. You can also quickly identify and diagnose errors in your application without waiting for a user to report them. With the version 0.20 SDK release onward, you can monitor common third-party packages, including MongoDB, MySQL, and Redis.

This quickstart guides you through adding the version 0.22 Application Insights SDK for Node.js to an existing Node.js web application.


To complete this quickstart:

  • You need an Azure Subscription and an existing Node.js web application.

If you don't have a Node.js web application, you can create one by following the Create a Node.js web app quickstart.

If you don't have an Azure subscription, create a free account before you begin.

Log in to the Azure portal

Log in to the Azure portal.

Enable Application Insights

Application Insights can gather telemetry data from any internet-connected application, regardless of whether it's running on-premises or in the cloud. Use the following steps to start viewing this data.

  1. Select Create a resource > Monitoring + Management > Application Insights.

    Adding Application Insights Resource

    A configuration box appears; use the following table to fill out the input fields.

    Settings Value Description
    Name Globally Unique Value Name that identifies the app you are monitoring
    Application Type Node.js Application Type of app you are monitoring
    Resource Group myResourceGroup Name for the new resource group to host App Insights data
    Location East US Choose a location near you, or near where your app is hosted
  2. Click Create.

Configure App Insights SDK

  1. Select Overview > Essentials > Copy your application's Instrumentation Key.

    New App Insights resource form

  2. Add the Application Insights SDK for Node.js to your application. From your app's root folder run:

    npm install applicationinsights --save
  3. Edit your app's first .js file and add the two lines below to the topmost part of your script. If you are using the Node.js quickstart app, you would modify the index.js file. Replace <instrumentation_key> with your application's instrumentation key.

    const appInsights = require('applicationinsights');
  4. Restart your app.


It takes 3-5 minutes before data begins appearing in the portal. If this app is a low-traffic test app, keep in mind that most metrics are only captured when there are active requests or operations occurring.

Start monitoring in the Azure portal

  1. You can now reopen the Application Insights Overview page in the Azure portal, where you retrieved your instrumentation key, to view details about your currently running application.

    Application Insights Overview Menu

  2. Click App map for a visual layout of the dependency relationships between your application components. Each component shows KPIs such as load, performance, failures, and alerts.

    Application Map

  3. Click on the App Analytics icon Application Map icon. This opens Application Insights Analytics, which provides a rich query language for analyzing all data collected by Application Insights. In this case, a query is generated for you that renders the request count as a chart. You can write your own queries to analyze other data.

    Analytics graph of user requests over a period of time

  4. Return to the Overview page and examine the Health Overview timeline. This dashboard provides statistics about your application health, including the number of incoming requests, the duration of those requests, and any failures that occur.

    Health Overview timeline graphs

    To enable the Page View Load Time chart to populate with client-side telemetry data, add this script to each page that you want to track:

    To collect end-user usage analytics about your application, 
    insert the following script into each page you want to track.
    Place this code immediately before the closing </head> tag,
    and before any other scripts. Your first data will appear 
    automatically in just a few seconds.
    <script type="text/javascript">
      var appInsights=window.appInsights||function(config){
        function i(config){t[config]=function(){var i=arguments;t.queue.push(function(){t[config].apply(t,i)})}}var t={config:config},u=document,e=window,o="script",s="AuthenticatedUserContext",h="start",c="stop",l="Track",a=l+"Event",v=l+"Page",y=u.createElement(o),r,f;y.src=config.url||"";u.getElementsByTagName(o)[0].parentNode.appendChild(y);try{t.cookie=u.cookie}catch(p){}for(t.queue=[],t.version="1.0",r=["Event","Exception","Metric","PageView","Trace","Dependency"];r.length;)i("track"+r.pop());return i("set"+s),i("clear"+s),i(h+a),i(c+a),i(h+v),i(c+v),i("flush"),config.disableExceptionTracking||(r="onerror",i("_"+r),f=e[r],e[r]=function(config,i,u,e,o){var s=f&&f(config,i,u,e,o);return s!==!0&&t["_"+r](config,i,u,e,o),s}),t
            instrumentationKey:"<insert instrumentation key>"
  5. Click on Browser from under the Investigate header. Here you find metrics related to the performance of your app's pages. You can click Add new chart to create additional custom views or select Edit to modify the existing chart types, height, color palette, groupings, and metrics.

    Server metrics graph

To learn more about monitoring Node.js, check out the additional App Insights Node.js documentation.

Clean up resources

If you plan to continue on to work with subsequent quickstarts or with the tutorials, do not clean up the resources created in this quick start. If you do not plan to continue, use the following steps to delete all resources created by this quick start in the Azure portal.

  1. From the left-hand menu in the Azure portal, click Resource groups and then click myResourceGroup.
  2. On your resource group page, click Delete, type myResourceGroup in the text box, and then click Delete.

Next steps