Begin replacing wit_bindgen with Rust SDK in integration tests

[ejmg]

This PR addresses #216.

I'll need some feedback on the intended behavior for these tests to ensure the integrations are still checking for the desired behavior and functionality.

[fibonacci1729]

Thanks for the PR @ejmg ! This all looks great. I think we can open a new issue regarding the note you left to make the logic of these tests (in the component) a little more robust. Would you mind dropping the note you left into an issue linking this PR?

[ejmg]

Sounds good to me. I am getting into the car to take off for a small camping trip until this Wednesday so I’ll file it myself if it can wait until then; I planned on seeing through the PR either way.

…

On Sat, Jun 4, 2022 at 4:47 PM Brian ***@***.***> wrote: ***@***.**** approved this pull request. Thanks for the PR @ejmg <https://github.com/ejmg> ! This all looks great. I think we can open a new issue regarding the note you left to make the logic of these tests (in the component) a little more robust. Would you mind dropping the note you left into an issue linking this PR? — Reply to this email directly, view it on GitHub <#534 (review)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AEK7ZPRTLB22AWU52OJGGDTVNPFGXANCNFSM5X2JQMDQ> . You are receiving this because you were mentioned.Message ID: ***@***.***>

[fibonacci1729]

Sounds great! Most of the Fermyon folks are returning from an offsite this week so no rush! Happy camping! 🏕

[ejmg]

Welp, camping plans changed. I'll open up a new issue with my comment and let me know if there is anything else I need to do on this PR before it gets merged.

[radu-matei]

This looks great, thank you, @ejmg!
I left a couple of very minor comments, and the commit needs to be GPG signed and signed-off.
(https://docs.github.com/en/authentication/managing-commit-signature-verification/signing-commits and https://git-scm.com/docs/git-commit#Documentation/git-commit.txt---signoff)

[ejmg]

Sorry for redundant commit, I missed the newline comment! I've signed off and verified my commits along with the suggested edits.

[ejmg]

@radu-matei and @fibonacci1729, I've updated this single test case to replicate the previous behavior of the test binary used by the integrations tests. To actually assert correctness, we would probably need to check the contents of the body but this is closer to correct behavior.

The one thing I'm wondering about right now (and as you'll see as a some NOTEs in the code) is that the return type of the component is no longer just a Response, but anyhow::Result. The error case for when the test asset file is not located is very different from the original code and I don't know how significant this is.

[radu-matei]

Re: your note — you're not actually changing the response of the Wasm component itself.
Rather, the Rust SDK takes care of that, and checks the anyhow::Result<Response> and returns the right value.

(for a bit more context on the WIT design for the HTTP component, which we might want to change eventually — the Response is directly sent to the client — so if we ever have a Rust error, we automatically send a 500 status back, without the user manually doing that.)

In terms of the commits, would you please squash to a single commit that is signed?

Thanks, and apologies for the git friction here..

[ejmg]

@radu-matei good to go?

[radu-matei]

Thank you for your contribution, @ejmg!

LGTM