Make parity.js usable by Node and Browser

[ngotchac]

Fixes #3471

const Api = require('/path/to/parity/js/.build/parity.js').Api;
const transport = new Api.Transport.Http('http://localhost:8545');
const api = new Api(transport);

api.eth
  .blockNumber()
  .then((block) => {
    console.log('At block', block.toFormat());
    process.exit(0);
  })
  .catch((e) => {
    console.error(e);
    process.exit(1);
  });

[tomusdrw]

Why not just use const fetch = require('isomorphic-fetch'); instead of relying on global variable to be present?

[jacogr]

Agreed with @tomusdrw here - just include isomorphic-fetch as part of the entry point (instead of whatwg-fetch) and no other hoops to jump through. (Just webpack lib build needs to include it, which it will)

[ngotchac]

So I'm not sure how this library is distributed on NPM... ? I had to do this trick because I thought the built JS file had to work in Node and in a browser

[tomusdrw]

Hmm, so I thought thatisomorphic-fetch is actually taking care of that (choosing right polyfill depending on the environment).
So my understanding was that we should not just "append that to the build", but rather alter the code using fetch to import it explicilty.

[ngotchac]

Well isomorphic-fetch loads the right module when in a Node environment, but when Webpack builds the library, it will try to get all the necessary code for the Node side of isomorphic-fetch anyway.

The real solution is to have a proper repo, with a build for browser and a build for Node (or as-is for Node in fact)

[ngotchac]

@jacogr @tomusdrw This should be better now. node-fetch is a dependency of the library, and the JS parity library only bundles whatwg-fetch.

[jacogr]

Ok, as discussed, seems it is the best approach.

I just want to test the library as built in both a Node & Browser environment before giving the ok. (Don't want to go cowboy and have a broken module on NPM. Will do so first thing in the morning.)

[gavofyork]

ci failing?

[jacogr]

@ngotchac Just added the in-progress label since there are issues you are working on in here.

[ngotchac]

@jacogr Ok it should be fine now.

You can try it with npm run test:npm for Node integration. In the browser, the window.Parity object is created with Api and Abi.

[jacogr]

s/Parity/parity/, need this to work -

const { Api } = window.parity;

const api = new Api(...);