feat: esm + tsup

[kanadgupta]

🚥 Resolves ISSUE_ID

🧰 Changes

TODO

• Look into using ESNext / bundler in tsconfig for core subpackage (based on my reading, I think the moduleResolution is the one that needs extra revisiting)

Current blockers:

• fetch-har mismatched types (hopefully solved by feat: esm and cjs exports fetch-har#427):

  api/packages/core/src/index.ts

  Line 126 in 0370988

  return fetchHar(har as Har, {

• Type discrepancy for CJS (very similar to what I wrote about in this comment)... I think this should be solved once we merge and release the following PRs:
  • fix: get default export working in both ESM/CJS oas#799
  • feat: esm and cjs exports fetch-har#427
  • These PRs are merged, but once a release is tagged with them: fix: esm issue in exports object remove-undefined-objects#86 fix: CJS export issue, CI cleanup remove-undefined-objects#88
• oas-to-har mismatched types (I believe this was fixed by readmeio/oas-to-har@a342179, fix: another attempt to get lodash working oas-to-har#248 and a bunch of other messy PRs before that):

  api/packages/core/src/index.ts

  Line 115 in 0370988

  const har = oasToHar(this.spec, operation, data, prepareAuth(this.auth, operation));

🧬 QA & Testing

Provide as much information as you can on how to test what you've done.

[kanadgupta]

Quick summary of the progress made in this PR thus far! I've gotten the functionality up and running where the api CLI will now do the following when you generate a TS SDK:

• ts-morph builds the TS files (same as before), and tsup is subsequently run on the index.ts entrypoint and it builds a dist/ directory with SDKs in CJS and ESM, along with their respective declaration files 🎉 in order to do this, the SDK's directory now includes:
  1. A tsup config within the package.json
  2. An exports object within the package.json that maps to the generated CJS/ESM dist files
  3. A tsconfig.json file
  4. typescript and tsup as dev-deps (this may or may not be necessary)

The SDK works and is fully typed for usage in TS and CJS, but needs #733 to be merged and published to the alpha channel in order to get it working properly in ESM.

You can head over to this repo to see the sandbox environment I was testing this in.

Next steps (non-exhaustive list, just rattling off stuff off the top of my head, doesn't all have to happen for this PR):

• Merge and publish feat: migrate api and core to ESM #733 to the alpha channel
• Update any downstream deps (remove-undefined-objects, oas, etc.) to the latest so they're properly loaded into the tsup-generated SDKs
• Add a README.md file and something to scripts (e.g., a prepare or prepack script) in the package.json so the user can regenerate the SDK as they please
• Make sure the package.json and the tsconfig in the codegen'd SDK directory are configured properly and are in a good enough spot so the user doesn't need additional config in order to successfully publish a usable SDK

[erunion]

the merge conflicts with this on main are a mess so i'm going to redo this in a new branch.

[kanadgupta]

for posterity, this work has been continued in #754