refactor: replace promises with async/await

[TimBeyer]

BREAKING CHANGE: Some functions that used to throw synchronously for things like bad parameters now reject the promise.
In many cases users may not have to do anything assuming the calls already happened within a promise chain, but in rare cases this may need some refactoring of error handling cases.

[codecov]

Codecov Report

Merging #496 (0399242) into master (e52ca41) will increase coverage by 2.85%.
The diff coverage is 96.00%.

@@            Coverage Diff             @@
##           master     #496      +/-   ##
==========================================
+ Coverage   62.50%   65.35%   +2.85%     
==========================================
  Files          12       12              
  Lines        1696     1882     +186     
  Branches      279      341      +62     
==========================================
+ Hits         1060     1230     +170     
- Misses        636      652      +16     

Impacted Files	Coverage Δ
lib/paged-sync.js	77.61% <95.65%> (+1.42%)	⬆️
lib/create-contentful-api.js	84.71% <96.15%> (+3.73%)	⬆️

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[marcolink]

I think the PR title should start with BREAKING CHANGE: to trigger a major release
https://github.com/semantic-release/semantic-release#commit-message-format

Would it make sense to add a migration section to the readme?

[TimBeyer]

According to https://www.conventionalcommits.org/en/v1.0.0/ the breaking change section goes into the footer or you add the exclamation mark after the type.

[TimBeyer]

Not sure what to write in a migration section. In theory this does not need changes in the vast majority of setups unless maybe the whole babel and regenerator stuff needs to be added somewhere. I'm not very familiar with those.

But overall the breaking changes are only in the validation of parameters for the sync calls from what I can tell, so you would probably only encounter those during development and not once things are fully set up.

[ghost]

🎉 This PR is included in version 8.0.0 🎉

The release is available on:

• npm package (@latest dist-tag)
• GitHub release

Your semantic-release bot 📦🚀

[mduleone]

Hello contentful team! Question about this change: Previously, we were able to run contentful in Node (v12.3.1) without issue, and now the same script is throwing an error. I understand that this includes breaking changes, but what would you recommend as the course of action to resolve something like this?

(node:72864) UnhandledPromiseRejectionWarning: ReferenceError: regeneratorRuntime is not defined
    at Object._getEntries (/Users/mattduleone/sites/next-web/node_modules/contentful/dist/contentful.node.js:6213:51)
    at Object.getEntries (/Users/mattduleone/sites/next-web/node_modules/contentful/dist/contentful.node.js:6191:24)
    at fetchContentfulData (/Users/mattduleone/sites/next-web/bin/contentful-refresh.js:59:33)
    at populateData (/Users/mattduleone/sites/next-web/bin/contentful-refresh.js:90:29)
    at Object.<anonymous> (/Users/mattduleone/sites/next-web/bin/contentful-refresh.js:111:1)
    at Module._compile (internal/modules/cjs/loader.js:774:30)
    at Object.Module._extensions..js (internal/modules/cjs/loader.js:785:10)
    at Module.load (internal/modules/cjs/loader.js:641:32)
    at Function.Module._load (internal/modules/cjs/loader.js:556:12)
    at Function.Module.runMain (internal/modules/cjs/loader.js:837:10)

[TimBeyer]

Oh that was definitely an unintended side effect of this change.
For now to unblock you, you could use https://www.npmjs.com/package/regenerator-runtime directly in your codebase.
For a proper fix I think we will bump the minimum node version required to run this because it seems a bit much to make everyone on a modern version of node use regenerator when all of this is natively supported.

[TimBeyer]

@mduleone we have a fix prepared in #498 that bumps the minimum version of node and thus gets rid of the dependency for regenerator.

[mduleone]

@TimBeyer thank you! Testing this out now!

[mduleone]

@TimBeyer Everything is working as expected. Thank you again!

[jesperp]

Hi, also getting the same error as @mduleone (ReferenceError: regeneratorRuntime is not defined), but inside the browser! (using Svelte, Typescript, Snowpack)

I'm just passed fixing this error:
contentful/contentful-sdk-core#120

And now trying to get a simple client.getEntries call working but getting the regeneratorRuntime error. Installing the regenerator-runtime package and importing it fixes this but can this be solved by contentful? I'm a bit javascript fatigued after many strange errors leading way down the rabbit hole of SO posts and github issues. Maybe the error is with svelte preprocessing / snowpack, I don't know! Hope to get some light on this issue anyhow!