otlp-transformer requires BigInt

[maximelkin]

What happened?

Steps to Reproduce

install @opentelemetry/otlp-transformer
build bundle for browsers with opentelemetry tracing

Expected Result

@opentelemetry/otlp-transformer fallbacks if BigInt not exists

Actual Result

it doesn't
https://github.com/open-telemetry/opentelemetry-js/blob/main/experimental/packages/otlp-transformer/src/common/index.ts#L21

Additional Details

As temporary workaround include bigint polyfill unconditionally for old browsers

OpenTelemetry Setup Code

No response

package.json

{
  "dependencies": {
    "@opentelemetry/api": "1.7.0",
    "@opentelemetry/core": "1.18.1",
    "@opentelemetry/exporter-trace-otlp-http": "0.45.1",
    "@opentelemetry/instrumentation": "0.45.1",
    "@opentelemetry/instrumentation-fetch": "0.45.1",
    "@opentelemetry/instrumentation-xml-http-request": "0.45.1",
    "@opentelemetry/resources": "1.18.1",
    "@opentelemetry/sdk-trace-base": "1.18.1",
    "@opentelemetry/sdk-trace-web": "1.18.1",
    "@opentelemetry/semantic-conventions": "1.18.1"
  }
}

Relevant log output

No response

[t2t2]

This kinda depends on decisions to be done in #4168 - likely anyting as old as IE would only be supported as not by default/user must add polyfills (be it with babel/preset-env w/ polyfills based on usage or whatever)

Other browsers have good enough support for BigInt https://caniuse.com/bigint

[jordanbd]

The use of BigInt within opentelemetry-js is a relatively recent change and localised entirely to the changes introduced from this PR. The PR even went to some effort to try and offer fallbacks when BigInt is unavailable (see here) but missed the NANOSECONDS constant.

I have a use case to support Chrome 40+ (but unfortunately below 67 where BigInt support is introduced). Given the near impossibility of polyfilling BigInt it would be nice if the NANOSECONDS constant could be guarded somehow, because even if #4168 results in me being stuck on an older version of opentelemetry-js I at least get the benefits of PR 4220.