Add Cabal flag to embed assets with TH

[fizruk]

@tibbe I see in #22 (comment) that you don't want TH in this package:

Using TH brings a host of other issues (cross compilation not working, etc) and since people who ship software to other machines to run there eventually will need to figure out how to ship whole packages of files (i.e. executable plus various templates, data files, etc) anyway, I don't think it's worth it.

However, we're pretty fine with TH in dependencies and we've been using servant-swagger-ui that embeds its assets just fine.

So would you mind if we add a Cabal flag (disabled by default) that would enable TH-based embedding?

[tibbe]

I will leave it up to @23Skidoo to decide as he's the primary maintainer nowadays.

[23Skidoo]

I think that TH is fine if it's hidden behind a flag, but if you do this please also add a CI configuration that tests the TH build variant.

[fizruk]

@23Skidoo Nice, we'll of course add a CI configuration to build TH version too!
We'll try to prepare a PR next week.

[Unisay]

@fizruk do you still plan to work on the PR ?

[nikita-volkov]

@fizruk Have you guys arrived at anything in the end with this?

[fizruk]

@nikita-volkov @Unisay we have been using our fork which is linked in this discussion and can be found at GetShopTV#1. We've been using it with Stack as follows:

- git: https://github.com/GetShopTV/ekg.git
  commit: f94af6a0fdd12e73a824c965c57053d7ce3e7ca1

We did not make the CI configuration for it at the time so we failed to report back here, sorry about that! Currently we are not using ekg much, so it has become a very low priority issue for us.

[brandon-leapyear]

✨ This is an old work account. Please reference @brandonchinn178 for all future communication ✨

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Bump. Would be great to get more discussion on this

[tibbe]

See #77 (comment)