Add TypeScript type definitions

[hassankhan]

Closes #28.

Since this project uses "Lambda" types for some things, for example event and context, I added @types/aws-lambda as a devDependency. My reasoning being anyone using TypeScript with Lambda should/would already have that package installed. I suppose we could add it to peerDependencies, but that would be annoying for non-TS users.

I still have a bit of cleanup to do, any issues/feedback is most certainly welcome 👍

[coveralls]

Pull Request Test Coverage Report for Build 167

• 0 of 0 changed or added relevant lines in 0 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage remained the same at 99.433%

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Totals
Change from base Build 163:	0.0%
Covered Lines:	501
Relevant Lines:	503

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💛 - Coveralls

[hassankhan]

Finished adding as much as I could glean from the docs 👍

[hassankhan]

Hi @jeremydaly, PR is ready for review 😄

[jeremydaly]

Awesome work, @hassankhan! I will give this a review in the next few days. Thanks for the PR!

[hassankhan]

Hi @jeremydaly, any chance you could review the PR soon? 😄

[jeremydaly]

I'm trying to get to it. It's been a busy week!

[Wintereise]

Hi, so, this might be a newbie question, but how do you use this?

Attempting to import any of these defined types throws an error, like so:

ERROR in G:\xen\manager\src\core\app\App.ts
./src/core/app/App.ts
[tsl] ERROR in G:\xen\manager\src\core\app\App.ts(3,10)
      TS2305: Module '"G:/xen/manager/node_modules/lambda-api/index"' has no exported member 'API'

Am I doing something wrong? Or it seems like the definitions haven't been marked as exported?

Looking at type definitions for similar projects, they all seem to mark their objects as exported -
Auth0: https://github.com/DefinitelyTyped/DefinitelyTyped/blob/master/types/auth0/index.d.ts
AWS Lambda: https://github.com/DefinitelyTyped/DefinitelyTyped/blob/master/types/aws-lambda/index.d.ts

@hassankhan

[Wintereise]

I added export to the classes + fixed the middleware signatures (use takes a callback for both errors and normal instances, not individual request/response/next instances).

I put that version of it here: https://github.com/Wintereise/lambda-api/commit/6acd197540d940445eb02e5afcbafad41f80bcd9

Can you guys review? If all good, I'll open another pull request and add the new Error types in 0.9.

@hassankhan @jeremydaly

[hassankhan]

Good catch @Wintereise, thanks for adding the exports. I've added a comment to your branch, aside from that all looks good to me 👍