async support

[nappa85]

Issue #14

The main loop has been converted into a future::LoopFn, who takes ownership on the Runtime.
Now it is possible to use async code inside lambdas.

By submitting this pull request

• I confirm that my contribution is made under the terms of the Apache 2.0 license.
• I confirm that I've made a best effort attempt to update all relevant documentation.

[davidbarsky]

@nappa85: Thanks for opening this! I think allowing folks to write async Lambda functions is a good idea, but given the upcoming stabilization of async/await and std::future, I was thinking of introducing a clean break and enforcing async/await first: https://paper.dropbox.com/doc/Lambda-Runtime-for-Rust-0.3--Ac2u75PLCibbXervTP2Rv5z_AQ-jLrDOiKk815YyIHLWva7M. Any thoughts?

cc: @softprops @iliana @sapessi

[softprops]

The vision looks super dope!

What I like about this pull is its relatively transparent for users to upgrade to the next version of the interface in this pull returning something that implements IntoFuture which gets the best of both worlds because todays Result interface should just work in most cases. That enables new future returning funcs and for sync funcs it should "just work" and no added syntactic cost.

I think the vision in the linked document could be possible even with this implementation as a graduating step. What I really liked in the doc was that it touched on a more painful part of todays interface, a less strict error representation! Satisfying HandlerError types have been a much more economic pain point than block_on calls.

I'm a fan of where the async/await syntax is going but I'm an even bigger fan of using a compromise that works on stable Rust today ;)

[davidbarsky]

Oh, I’m really sorry! I’m in favor of merging this change, and I have no idea why I said “introducing async/await first!” I must’ve not been paying attention when typing. Really sorry!

…

________________________________ From: Doug Tangren <[email protected]> Sent: Friday, May 10, 2019 11:06 PM To: awslabs/aws-lambda-rust-runtime Cc: David Barsky; Comment Subject: Re: [awslabs/aws-lambda-rust-runtime] async support (#106) The vision looks super dope! What I like about this pull is its relatively transparent for users to upgrade to the next version of the interface in this pull returning something that implements IntoFuture which gets the best of both worlds because todays Result interface should just work in most cases. That enables new future returning funcs and for sync funcs it should "just work" and no added syntactic cost. I think the vision in the linked document could be possible even with this implementation as a graduating step. What I really liked in the doc was that it touched on a more painful part of todays interface, a less strict error representation! Satisfying HandlerError types have been a much more economic pain point than block_on calls. I'm a fan of where the async/await syntax is going but I'm an even bigger fan of using a compromise that works on stable Rust today ;) — You are receiving this because you commented. Reply to this email directly, view it on GitHub<#106 (comment)>, or mute the thread<https://github.com/notifications/unsubscribe-auth/AAPY2PWDOFRPV5LKA2WFGW3PUYZ27ANCNFSM4HMBXCWQ>.

[nappa85]

Sorry for late reply.
Yes, my intent was to offer a drop-in upgrade, so existing implementations should not be affected, while giving everyone the ability to use futures-powered-lambdas.
I know about async/await stabilization will probably happen in July with 1.36, you can release this as a version bump now and start working on a refactory that will end up in a new major version to be released after July.

[davidbarsky]

Thanks for this! Can those small nits be addressed and then we can merge/release?

[nappa85]

Hello, sorry to bother you all...
Are there still open tasks blocking this merge?
Thank you

[davidbarsky]

Not a bother! I don’t have any additional concerns merging this and would be happy if @sapessi or @softprops don’t have any concerns.

…

________________________________ From: Marco Napetti <[email protected]> Sent: Tuesday, May 28, 2019 6:09 AM To: awslabs/aws-lambda-rust-runtime Cc: David Barsky; Comment Subject: Re: [awslabs/aws-lambda-rust-runtime] async support (#106) Hello, sorry to bother you all... Are there still open tasks blocking this merge? Thank you — You are receiving this because you commented. Reply to this email directly, view it on GitHub<#106?email_source=notifications&email_token=AAPY2PWVGWMJCAIS6BPDHP3PXUAHNA5CNFSM4HMBXCW2YY3PNVWWK3TUL52HS4DFVREXG43VMVBW63LNMVXHJKTDN5WW2ZLOORPWSZGODWLURDI#issuecomment-496453773>, or mute the thread<https://github.com/notifications/unsubscribe-auth/AAPY2PXCPY3IRD24EWP2GCDPXUAHNANCNFSM4HMBXCWQ>.

[softprops]

I'm feelin it

[nappa85]

Bump
A month has passed, still no news?

[lvicentesanchez]

hi! what's the status of this PR? I would really like to start using async lambdas.

[lvicentesanchez]

@davidbarsky @sapessi @softprops ?

[mies]

any update on this @davidbarsky @nappa85 ?

[sbditto85]

bump. update?

[drusellers]

Just checking in. :)

[davidbarsky]

You should be able to pull from the master branch and take this for a spin. It doesn’t suck.

[softprops]

I think this can be closed now

[brainstorm]

Yes, this can be closed, async works very well on rust-lambda for a while now 🚀

[coltonweaver]

Going to close this PR as it seems all is well here!