Application Insights overriding default endpoints

<ApplicationInsights>
  ...
  <TelemetryModules>
    <Add Type="Microsoft.ApplicationInsights.Extensibility.PerfCounterCollector.QuickPulse.QuickPulseTelemetryModule, Microsoft.AI.PerfCounterCollector">
      <QuickPulseServiceEndpoint>Custom_QuickPulse_Endpoint_Address</QuickPulseServiceEndpoint>
    </Add>
  </TelemetryModules>
   ...
  <TelemetrySinks>
    <Add Name = "default">
      <TelemetryChannel>
         <EndpointAddress>TelemetryChannel_Endpoint_Address</EndpointAddress>
      </TelemetryChannel>
    </Add>
  </TelemetrySinks>
  ...
  <ApplicationIdProvider Type="Microsoft.ApplicationInsights.Extensibility.Implementation.ApplicationId.ApplicationInsightsApplicationIdProvider, Microsoft.ApplicationInsights">
    <ProfileQueryEndpoint>Profile_Query_Endpoint_address</ProfileQueryEndpoint>
  </ApplicationIdProvider>
  ...
</ApplicationInsights>

Modify the appsettings.json file in your project as follows to adjust the main endpoint:

"ApplicationInsights": {
    "InstrumentationKey": "instrumentationkey",
    "TelemetryChannel": {
      "EndpointAddress": "TelemetryChannel_Endpoint_Address"
    }
  }

The values for Live Metrics and the Profile Query Endpoint can only be set via code. To override the default values for all endpoint values via code, make the following changes in the ConfigureServices method of the Startup.cs file:

using Microsoft.ApplicationInsights.Extensibility.Implementation.ApplicationId;
using Microsoft.ApplicationInsights.Extensibility.PerfCounterCollector.QuickPulse; //Place at top of Startup.cs file

   services.ConfigureTelemetryModule<QuickPulseTelemetryModule>((module, o) => module.QuickPulseServiceEndpoint="QuickPulse_Endpoint_Address");

   services.AddSingleton<IApplicationIdProvider, ApplicationInsightsApplicationIdProvider>(_ => new ApplicationInsightsApplicationIdProvider() { ProfileQueryEndpoint = "Profile_Query_Endpoint_address" });

   services.AddSingleton<ITelemetryChannel>(_ => new ServerTelemetryChannel() { EndpointAddress = "TelemetryChannel_Endpoint_Address" });

    //Place in the ConfigureServices method. Place this before services.AddApplicationInsightsTelemetry("instrumentation key"); if it's present

For Azure Functions it is now recommended to use connection strings set in the Function's Application settings. To access Application settings for your function from within the functions pane select Settings > Configuration > Application settings.

Name: APPLICATIONINSIGHTS_CONNECTION_STRING Value: Connection String Value

Modify the applicationinsights.xml file to change the default endpoint address.

<?xml version="1.0" encoding="utf-8"?>
<ApplicationInsights xmlns="http://schemas.microsoft.com/ApplicationInsights/2013/Settings">
  <InstrumentationKey>ffffeeee-dddd-cccc-bbbb-aaaa99998888</InstrumentationKey>
  <TelemetryModules>
    <Add type="com.microsoft.applicationinsights.web.extensibility.modules.WebRequestTrackingTelemetryModule"/>
    <Add type="com.microsoft.applicationinsights.web.extensibility.modules.WebSessionTrackingTelemetryModule"/>
    <Add type="com.microsoft.applicationinsights.web.extensibility.modules.WebUserTrackingTelemetryModule"/>
  </TelemetryModules>
  <TelemetryInitializers>
    <Add type="com.microsoft.applicationinsights.web.extensibility.initializers.WebOperationIdTelemetryInitializer"/>
    <Add type="com.microsoft.applicationinsights.web.extensibility.initializers.WebOperationNameTelemetryInitializer"/>
    <Add type="com.microsoft.applicationinsights.web.extensibility.initializers.WebSessionTelemetryInitializer"/>
    <Add type="com.microsoft.applicationinsights.web.extensibility.initializers.WebUserTelemetryInitializer"/>
    <Add type="com.microsoft.applicationinsights.web.extensibility.initializers.WebUserAgentTelemetryInitializer"/>
  </TelemetryInitializers>
  <!--Add the following Channel value to modify the Endpoint address-->
  <Channel type="com.microsoft.applicationinsights.channel.concrete.inprocess.InProcessTelemetryChannel">
  <EndpointAddress>TelemetryChannel_Endpoint_Address</EndpointAddress>
  </Channel>
</ApplicationInsights>

Spring Boot

Modify the application.properties file and add:

azure.application-insights.channel.in-process.endpoint-address= TelemetryChannel_Endpoint_Address

var appInsights = require("applicationinsights");
appInsights.setup('INSTRUMENTATION_KEY');
appInsights.defaultClient.config.endpointUrl = "TelemetryChannel_Endpoint_Address"; // ingestion
appInsights.defaultClient.config.profileQueryEndpoint = "Profile_Query_Endpoint_address"; // appid/profile lookup
appInsights.defaultClient.config.quickPulseHost = "QuickPulse_Endpoint_Address"; //live metrics
appInsights.Configuration.start();

The endpoints can also be configured through environment variables:

Instrumentation Key: "APPINSIGHTS_INSTRUMENTATIONKEY"
Profile Endpoint: "Profile_Query_Endpoint_address"
Live Metrics Endpoint: "QuickPulse_Endpoint_Address"

The current Snippet (listed below) is version "5", the version is encoded in the snippet as sv:"#" and the current version is also available on GitHub.

<script type="text/javascript">
!function(T,l,y){var S=T.location,k="script",D="instrumentationKey",C="ingestionendpoint",I="disableExceptionTracking",E="ai.device.",b="toLowerCase",w="crossOrigin",N="POST",e="appInsightsSDK",t=y.name||"appInsights";(y.name||T[e])&&(T[e]=t);var n=T[t]||function(d){var g=!1,f=!1,m={initialize:!0,queue:[],sv:"5",version:2,config:d};function v(e,t){var n={},a="Browser";return n[E+"id"]=a[b](),n[E+"type"]=a,n["ai.operation.name"]=S&&S.pathname||"_unknown_",n["ai.internal.sdkVersion"]="javascript:snippet_"+(m.sv||m.version),{time:function(){var e=new Date;function t(e){var t=""+e;return 1===t.length&&(t="0"+t),t}return e.getUTCFullYear()+"-"+t(1+e.getUTCMonth())+"-"+t(e.getUTCDate())+"T"+t(e.getUTCHours())+":"+t(e.getUTCMinutes())+":"+t(e.getUTCSeconds())+"."+((e.getUTCMilliseconds()/1e3).toFixed(3)+"").slice(2,5)+"Z"}(),iKey:e,name:"Microsoft.ApplicationInsights."+e.replace(/-/g,"")+"."+t,sampleRate:100,tags:n,data:{baseData:{ver:2}}}}var h=d.url||y.src;if(h){function a(e){var t,n,a,i,r,o,s,c,u,p,l;g=!0,m.queue=[],f||(f=!0,t=h,s=function(){var e={},t=d.connectionString;if(t)for(var n=t.split(";"),a=0;a<n.length;a++){var i=n[a].split("=");2===i.length&&(e[i[0][b]()]=i[1])}if(!e[C]){var r=e.endpointsuffix,o=r?e.location:null;e[C]="https://"+(o?o+".":"")+"dc."+(r||"services.visualstudio.com")}return e}(),c=s[D]||d[D]||"",u=s[C],p=u?u+"/v2/track":d.endpointUrl,(l=[]).push((n="SDK LOAD Failure: Failed to load Application Insights SDK script (See stack for details)",a=t,i=p,(o=(r=v(c,"Exception")).data).baseType="ExceptionData",o.baseData.exceptions=[{typeName:"SDKLoadFailed",message:n.replace(/\./g,"-"),hasFullStack:!1,stack:n+"\nSnippet failed to load ["+a+"] -- Telemetry is disabled\nHelp Link: https://go.microsoft.com/fwlink/?linkid=2128109\nHost: "+(S&&S.pathname||"_unknown_")+"\nEndpoint: "+i,parsedStack:[]}],r)),l.push(function(e,t,n,a){var i=v(c,"Message"),r=i.data;r.baseType="MessageData";var o=r.baseData;return o.message='AI (Internal): 99 message:"'+("SDK LOAD Failure: Failed to load Application Insights SDK script (See stack for details) ("+n+")").replace(/\"/g,"")+'"',o.properties={endpoint:a},i}(0,0,t,p)),function(e,t){if(JSON){var n=T.fetch;if(n&&!y.useXhr)n(t,{method:N,body:JSON.stringify(e),mode:"cors"});else if(XMLHttpRequest){var a=new XMLHttpRequest;a.open(N,t),a.setRequestHeader("Content-type","application/json"),a.send(JSON.stringify(e))}}}(l,p))}function i(e,t){f||setTimeout(function(){!t&&m.core||a()},500)}var e=function(){var n=l.createElement(k);n.src=h;var e=y[w];return!e&&""!==e||"undefined"==n[w]||(n[w]=e),n.onload=i,n.onerror=a,n.onreadystatechange=function(e,t){"loaded"!==n.readyState&&"complete"!==n.readyState||i(0,t)},n}();y.ld<0?l.getElementsByTagName("head")[0].appendChild(e):setTimeout(function(){l.getElementsByTagName(k)[0].parentNode.appendChild(e)},y.ld||0)}try{m.cookie=l.cookie}catch(p){}function t(e){for(;e.length;)!function(t){m[t]=function(){var e=arguments;g||m.queue.push(function(){m[t].apply(m,e)})}}(e.pop())}var n="track",r="TrackPage",o="TrackEvent";t([n+"Event",n+"PageView",n+"Exception",n+"Trace",n+"DependencyData",n+"Metric",n+"PageViewPerformance","start"+r,"stop"+r,"start"+o,"stop"+o,"addTelemetryInitializer","setAuthenticatedUserContext","clearAuthenticatedUserContext","flush"]),m.SeverityLevel={Verbose:0,Information:1,Warning:2,Error:3,Critical:4};var s=(d.extensionConfig||{}).ApplicationInsightsAnalytics||{};if(!0!==d[I]&&!0!==s[I]){var c="onerror";t(["_"+c]);var u=T[c];T[c]=function(e,t,n,a,i){var r=u&&u(e,t,n,a,i);return!0!==r&&m["_"+c]({message:e,url:t,lineNumber:n,columnNumber:a,error:i}),r},d.autoExceptionInstrumented=!0}return m}(y.cfg);function a(){y.onInit&&y.onInit(n)}(T[t]=n).queue&&0===n.queue.length?(n.queue.push(a),n.trackPageView({})):a()}(window,document,{
src: "https://js.monitor.azure.com/scripts/b/ai.2.min.js", // The SDK URL Source
// name: "appInsights", // Global SDK Instance name defaults to "appInsights" when not supplied
// ld: 0, // Defines the load delay (in ms) before attempting to load the sdk. -1 = block page load and add to head. (default) = 0ms load after timeout,
// useXhr: 1, // Use XHR instead of fetch to report failures (if available),
crossOrigin: "anonymous", // When supplied this will add the provided value as the cross origin attribute on the script tag
// onInit: null, // Once the application insights instance has loaded and initialized this callback function will be called with 1 argument -- the sdk instance (DO NOT ADD anything to the sdk.queue -- As they won't get called)
cfg: { // Application Insights Configuration
    instrumentationKey:"INSTRUMENTATION_KEY",
    endpointUrl: "TelemetryChannel_Endpoint_Address"
}});
</script>

For guidance on modifying the ingestion endpoint for the opencensus-python SDK consult the opencensus-python repo.