Typescript improvements and Address Checksumming

[mickys]

Description

1. Cleanup and Typescript improvements.

• Cleaned up repository of .lock files
• Added util, schnorr, znode, exports to index for easy import
• Added prepare for /dist generation upon install so types can actually be used in TypeScript

1.1. New usage example no longer requires "Zilliqa" class instantiation to get to the util library

import { util } from 'zilliqa-js';

util.isAddress( "not_an_address" ); // false
util.isAddress( "7bb3b0e8a59f3f61d9bff038f4aeb42cae2ecce8" ); // true

2. Address Checksumming based on EIP-55

see: https://github.com/ethereum/EIPs/blob/master/EIPS/eip-55.md

2.1. Methods:

methods support both standard and 0x prepended addresses

• toChecksumAddress(address: string): string
• isValidChecksumAddress(address: string): boolean

2.2. Usage Example

import { util } from 'zilliqa-js';

const address = "0x7bb3b0e8a59f3f61d9bff038f4aeb42cae2ecce8";
const checksummed = util.toChecksumAddress( address );
// 0x7bB3b0E8A59f3f61d9BFf038f4AEB42Cae2eccE8

util.isValidChecksumAddress( checksummed ); // true
util.isValidChecksumAddress( address ); // false

methods support both standard and 0x prepended addresses as inputs

const lowercaseAddress = "7bb3b0e8a59f3f61d9bff038f4aeb42cae2ecce8";

util.toChecksumAddress( lowercaseAddress );
// 0x7bB3b0E8A59f3f61d9BFf038f4AEB42Cae2eccE8

util.toChecksumAddress( "0x" + lowercaseAddress );
// 0x7bB3b0E8A59f3f61d9BFf038f4AEB42Cae2eccE8

util.isValidChecksumAddress( "0x7bB3b0E8A59f3f61d9BFf038f4AEB42Cae2eccE8".replace('0x', '') );
// true
util.isValidChecksumAddress( "0x7bB3b0E8A59f3f61d9BFf038f4AEB42Cae2eccE8" );
// true

2.3. Tests

Added tests for these in tests/util.spec.ts

Review Suggestion

Checksumming uses: hashjs.sha256() since it was already imported in the util class

Status

Implementation

• ready for review

[edison0xyz]

What is the purpose of prepare?

[mickys]

If the package is used as a dependency in a project, we should be able to use the types provided in the dist folder.

"prepare" tells the npm installer to run a build once the package is installed, in order to generate the dist directory.

[iantanwx]

@mickys I think the typings are already included in the dist folder as part of the NPM distribution. It seems I forgot to add the types field. Can you add it in? If you do, I don't think prepare is necessary.

[iantanwx]

See https://www.typescriptlang.org/docs/handbook/declaration-files/publishing.html for reference

[mickys]

There is a "typings": "dist/index.d.ts" in the package.json file, which is synonymous to types. So if it was supposed to work it should have.
( unless yarn publish / npm.org does this, which i'm unable to test )

There are 3 ways these can be provided to the user as far as i'm aware

1. Provide said typings in the "dist" folder or another one "lib" maybe.
   this does create the dependency of building before committing

2. Create a typings module and PR it to @types ( https://github.com/DefinitelyTyped/DefinitelyTyped ) to be included when needed.
   Does take some time to get accepted thou and afaik these are meant for modules that don't do it themselves

3. Use "prepare" to generate dist or lib folder.

I'm fine with whichever option you guys prefer, thou

[iantanwx]

@mickys you're right. It looks like there has been some mistake when the build was published. We'll rectify this issue. prepare should not be necessary.

@edisonljh which folder do we normally publish?

[mickys]

I've removed the prepare instruction from the PR.
Feel free to merge then do the changes required.

[iantanwx]

Thanks @mickys. This looks good. Would you be able to add a few more test vectors for the checksum tests? You can do something like checksum.fixtures.ts.

[iantanwx]

More test vectors to be added.

[mickys]

Added more checksum test vectors, see checksum.fixtures.ts

[mickys]

I've removed the prepare instruction from the PR.
Feel free to merge then do the types required changes you're planning.

[edison0xyz]

This looks good! Thanks, this is a good PR! 👍

[iantanwx]

Thanks @mickys !