Use sha.js instead of full crypto in browser

[pelle]

Only use sha.js per suggestions from @dignifiedquire here ipfs-inactive/js-ipfs-http-client#353

Not sure how much of an effect it will have on the distribution size

[pelle]

Failure in Travis is due to lint complaining about digest function names:

'''
49:10 error Identifier 'gsha2_256' is not in camel case camelcase
53:10 error Identifier 'gsha2_512' is not in camel case camelcase
'''

I suppose it could be fixed, since I guess these aren't called externally.

[dignifiedquire]

To make this really efficient we need to do a bit more work, isNode is an npm module, and not a static variable, that means the require('crypto') does not get optimised away.

What we want is something like this

let createHash

if (buildingForBrowser) {
  createHash = require('sha.js')
} else {
  createHash = require('crypto').createHash
}

and then let our build tool define buildingForBrowser. This way when building for the browser this would be transformed into

let createHash

if (true) {
  createHash = require('sha.js')
} else {
  // unreachable code
  createHash = require('crypto').createHash
}

This in turn would be then properly analyzable by webpack & uglify and they could remove the unreachable code.

[dignifiedquire]

@pelle I just finished #12 which uses webcrypto instead of JavaScript fallbacks in the browser reducing the size even further :)

[daviddias]

@pelle did you had the chance to check @dignifiedquire suggestions?

[pelle]

Sorry I missed this. I guess I was at devcon and all was a blur. Having a look now.

[pelle]

Looks great. Great progress @dignifiedquire and @diasdavid

[kumavis]

can also set crypto: false in the browser field in package.json

[hacdias]

@diasdavid I think this one could be closed since it is a bit old, has a lot of conflicts, and js-multihashing is using webcrypto now.

[daviddias]

@hacdias only multihashing-async is using webcrypto, not this one.

[hacdias]

Oh. Sorry. Should we use web crypto on this one too?

…

On Tue, 2 Jan 2018 at 17:17, David Dias ***@***.***> wrote: @hacdias <https://github.com/hacdias> only multihashing-async is using webcrypto, not this one. — You are receiving this because you were mentioned. Reply to this email directly, view it on GitHub <#10 (comment)>, or mute the thread <https://github.com/notifications/unsubscribe-auth/AFMdsK2uTRZ3h2MsOFDd6dMzYsgjfKNnks5tGmSvgaJpZM4JpVIB> .

[daviddias]

@hacdias the thing is that you can't. WebCrypto is async only (that is why there is a multihashing-async)