Implementation if no instrumentation key provided

[PaulInglis]

Hello,

This is more a question than an issue.

We have (as I'm sure others will) the situation where our product will be deployed to various SDLC environments and for some of these environments (e.g. localhost or load testing) we do not wish App Insights to be recorded....or more correctly, we won't assign an instrumentation key (IK) in the environment variables.

What is the best way to handle this? Simply not call the init function if no IK is found? If so, how does that affect withTracking or calls?
Should we have 2 different component exports based on whether we have an IK existing or not?

Any other guidance around best practice for this would be appreciated.

[pviotti]

react-appinsights is fairly transparent on the configuration of App Insights: it just builds an internal instance by passing the configuration that you feed to the init method.
App Insights itself throws an error in the constructor if it doesn't find the instrumentation key. So all the subsequent calls to withTracking and trackPageView would fail with undefined has not xyz property error if you initialize react-appinsights without IK, or with IK as empty string IK.
So the suggested practice here is to use a non-empty string as IK for environments in which you don't care sending telemetry back to App Insights.

As a reminder, another best practice about using different environments is to use different AppInsights resources (thus, different instrumentation keys), as explained here.

(I'll keep this open until we document this practice better and write some tests in the upcoming v3, which supports the new AppInsights SDK)

[mikegoatly]

@pviotti Is there a recommended way to pass the instrumentation key to the client initialization? As you mentioned, it's good practice to have a different key per environment, so it would need to be passed to dynamically provided in some form or another.

[PaulInglis]

I did it with

const instrumentationKey: string = process.env.REACT_APP_INSTRUMENTATION_KEY || 'xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxxx';

And then pass that variable into the initialise function

[pviotti]

There's no recommended way of storing and retrieving the instrumentation key: it depends on where you decide to store such information. I'd say environment variables are good enough for this. This blog post gives an overview of how to use them in React.

Ref: #microsoft/ApplicationInsights-JS#281