feat(rum-core): add apmRequest config typescript type

[ReneWerner87]

@hmdhk you had forgotten the typescript files, can you please check if it fits like this

the feature is great and we use it, thanks for your effort

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• Start Time: 2022-07-04T14:56:13.001+0000

• Duration: 77 min 1 sec

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[ReneWerner87]

/test

[devcorpio]

Hi @ReneWerner87,

Thanks for your contribution!

TL;DR:

The types have to be a bit different:

    apmRequest?: (
      requestParams: {
        xhr: XMLHttpRequest
        url: string
        method: string
        payload: string | undefined
        headers: Record<string, string> | undefined
      },
    ) => boolean

Context:

When apmRequest is set the agent execute it on two different situations:

1. when fetching central config. This only happens when centralConfig is set to true.
2. when sending events/beacons to the APM server

On the case of the central config the arguments the agent provides are xhr, url, and method. (payload and headers are undefined).

On the case of the events/beacons the payload and headers arguments are provided, but payload type is a string and headers is an object literal.

[ReneWerner87]

Hi @ReneWerner87,

Thanks for your contribution!

TL;DR:

The types have to be a bit different:

    apmRequest?: (
      requestParams: {
        xhr: XMLHttpRequest
        url: string
        method: string
        payload: string | undefined
        headers: Record<string, string> | undefined
      },
    ) => boolean

Context:

When apmRequest is set the agent execute it on two different situations:

1. when fetching central config. This only happens when centralConfig is set to true.
2. when sending events/beacons to the APM server

On the case of the central config the arguments the agent provides are xhr, url, and method. (payload and headers are undefined).

On the case of the events/beacons the payload and headers arguments are provided, but payload type is a string and headers is an object literal.

thx, i changed the types

[apmmachine]

📦 Bundlesize report

Filename	Size(bundled)	Size(gzip)	Diff(gzip)
elastic-apm-opentracing.umd.min.js	66.0 KiB	21.0 KiB	💚 0 Bytes
elastic-apm-rum.umd.min.js	59.9 KiB	19.5 KiB	💚 0 Bytes

[apmmachine]

🌐 Coverage report

Name	Metrics % (covered/total)	Diff
Packages	100.0% (8/8)	💚
Files	98.148% (53/54)	👍 0.109
Classes	98.148% (53/54)	👍 0.109
Methods	97.406% (413/424)	👍 0.05
Lines	95.26% (2110/2215)	👎 -0.042
Conditionals	86.278% (1050/1217)	👎 -0.143

[devcorpio]

LGTM! 🎉 , This will be part of the next release we do.