feat: Fetch support

[benjackwhite]

Changes

Fixes #547

Some environments don't support xhr at all anymore like chrome extensions. This PR adds fetch as the default method when available.

This PR makes it possible to set the api_transport to fetch.

It also deprecates support for the on_xhr_error in a slightly breaking way. Decided it is better to not call it than to call it with a broken interface. This should have a low impact (it is anyways edge casey in terms of only getting called when things fail).

TODO

• Add tests for the fetch implementation (followup)
• "Flag" the fetch implementation so we can gradually test it for real

Checklist

• Tests for new code (see advice on the tests we use)
• Accounted for the impact of any changes across different browsers

[github-actions]

Size Change: +6.18 kB (+1%)

Total Size: 772 kB

Filename	Size	Change
dist/array.full.js	181 kB	+1.29 kB (+1%)
dist/array.js	122 kB	+1.28 kB (+1%)
dist/es.js	122 kB	+1.28 kB (+1%)
dist/exception-autocapture.js	11.9 kB	-16 B (0%)
dist/module.js	123 kB	+1.28 kB (+1%)
dist/recorder-v2.js	105 kB	+1.07 kB (+1%)

ℹ️ View Unchanged

Filename	Size
dist/recorder.js	58.5 kB
dist/surveys.js	48.7 kB

_{compressed-size-action}

[posthog-bot]

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[posthog-bot]

This PR hasn't seen activity in a week! Should it be merged, closed, or further worked on? If you want to keep it open, post a comment or remove the stale label – otherwise this will be closed in another week.

[posthog-bot]

This PR hasn't seen activity in a week! Should it be merged, closed, or further worked on? If you want to keep it open, post a comment or remove the stale label – otherwise this will be closed in another week.

[posthog-bot]

This PR hasn't seen activity in a week! Should it be merged, closed, or further worked on? If you want to keep it open, post a comment or remove the stale label – otherwise this will be closed in another week.

[posthog-bot]

This PR hasn't seen activity in a week! Should it be merged, closed, or further worked on? If you want to keep it open, post a comment or remove the stale label – otherwise this will be closed in another week.

[posthog-bot]

This PR hasn't seen activity in a week! Should it be merged, closed, or further worked on? If you want to keep it open, post a comment or remove the stale label – otherwise this will be closed in another week.

[posthog-bot]

This PR was closed due to lack of activity. Feel free to reopen if it's still relevant.

[mariusandra]

In general, 👍
I do know that we have people using posthog-js with IE11, who might be affected by this if we (eventually) slim the bundle and remove the old XHR route. Not sure what to do with them

[benjackwhite]

In general, 👍 I do know that we have people using posthog-js with IE11, who might be affected by this if we (eventually) slim the bundle and remove the old XHR route. Not sure what to do with them

I don't think we need to remove it tbh. Main thing is this unblocks certain envs where only fetch is supported which is good enough for now