BasePlugin.js - Critical dependency warning in webpack

[lukomwro]

What version of OpenTelemetry are you using?

0.4.0

What version of Node are you using?

12.4.0

What did you do?

I've added telemetry script with some plugins UserInteractionPlugin and DocumentLoad. The code is copied from examples

import { DocumentLoad } from '@opentelemetry/plugin-document-load';
import { UserInteractionPlugin } from '@opentelemetry/plugin-user-interaction'
import { ZoneScopeManager } from '@opentelemetry/scope-zone'
import { ConsoleSpanExporter, SimpleSpanProcessor } from '@opentelemetry/tracing'
import { WebTracerProvider } from '@opentelemetry/web'

const providerWithZone = new WebTracerProvider({
  scopeManager: new ZoneScopeManager(),
  plugins: [new UserInteractionPlugin(), new DocumentLoad()],
})

providerWithZone.addSpanProcessor(new SimpleSpanProcessor(new ConsoleSpanExporter()))

console.log('telemetry started')

What did you expect to see?

Complication without warnings

What did you see instead?

Compiled with warnings.

./node_modules/@opentelemetry/core/build/src/trace/instrumentation/BasePlugin.js
Critical dependency: the request of a dependency is an expression

Search for the keywords to learn more about each warning.
To ignore, add // eslint-disable-next-line to the line before.

Additional context

I'm using the latest create-react-app boilerplate with TypeScript template.

Webpack version 4.41.5

[dyladan]

This happens because the Plugin system uses a dynamic require statement in order to load node plugins. It should not affect the behavior of web plugins, but you will still get the warning because webpack does not know that the dynamic require only runs in node. I will look into fixes for this.

[stephanos]

I just ran into the same issue. Is there a workaround? It seems like it's basically bricked when using webpack.

[dyladan]

it should still work with warnings

[stephanos]

Hm, the build step of my React app completely fails.

I fixed it with this:

"postinstall": "file=./node_modules/@opentelemetry/core/build/src/trace/instrumentation/BasePlugin.js && awk '!/ = require/' $file > tmp && mv tmp $file",

(not proud of it)

[dyladan]

Do plugins still load correctly after you've done that? The require isn't needed for web plugins so it should be ok. This will probably require changing to a platform specific base plugin to fix @mayurkale22 @obecny WDYT?

[stephanos]

Yes, I'm using the XMLHttpRequestPlugin and it works fine.

as for fixing this, maybe consider adding a big if statement at the top of that internal function that checks for a constant that Webpack knows and it then (hopefully) just ignores the code in there if it's not on Node?