Add ability to set HttpHeaders via plugin options

[adamyeats]

Discussed in #625

^{Originally posted by ShravanSunder December 8, 2023}
I wanted to use this with grafana cloud to view data in cloudflare analytics engine that uses clickhouse. https://developers.cloudflare.com/analytics/analytics-engine/grafana/

They need use to use authorisation header with https. How can this be done in this plug in?

If not can we request this feature?

[SpencerTorres]

This would be useful. Some questions:

1. Are there any headers we would want to restrict adding? (Hop headers?)
2. Should it be a generic input for an array of headers, or should we just add Authorization for now?
3. Would any of these fields need to be stored securely? (Such as Authorization containing tokens)

[ShravanSunder]

@SpencerTorres this is the link to cloudflare's click house offering which would be great to connect to grafana: https://developers.cloudflare.com/analytics/analytics-engine/grafana/#grafana-plugin-setup

Configure the plugin as follows:

URL: https://api.cloudflare.com/client/v4/accounts/<account_id>/analytics_engine/sql. Replace <account_id> with your 32 character account ID (available in the Cloudflare dashboard).
Leave all auth settings off.
Add a custom header with a name of Authorization and value set to Bearer <token>. Replace <token> with suitable API token string (refer to the [SQL API docs](https://developers.cloudflare.com/analytics/analytics-engine/sql-api/#authentication) for more information on this).
No other options need to be set.

[ShravanSunder]

@adamyeats Any thoughts on when you would be able to support this. thanks :)

[adamyeats]

@ShravanSunder See #633

[SpencerTorres]

As @adamyeats mentioned, we have a PR open to add this to the v4 branch in #633. v4 will be released soon but if you want to build your own branch asap, I recommend using my v4-fixes branch from #666 which includes the latest version of v4 (and includes the http header changes)

[ShravanSunder]

@SpencerTorres i'm attempting to use this with grafana cloud, so i'll wait for the PR to be merged :) thanks!

[SpencerTorres]

@ShravanSunder Hey! v4 is available now on the plugin catalog if you want to give it a go. I'm gonna close this issue now that the feature is available. Thanks!