Crypto Finance Development Kit for WebAssembly (CFD-JS-WASM)

WebAssembly of cfd libraries (by JSON format API)

WebAssembly Example

• example

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Overview

This library is development kit for crypto finance application. Useful when developing applications for cryptocurrencies.

Target Network

• Bitcoin
• Liquid Network

Support function by cfd

• Bitcoin
  • Bitcoin Script (builder, viewer)
  • Transaction
    • Create, Parse, Decode
    • Simple pubkey-hash sign / verify
    • Estimate Fee
    • Coin Selection (FundRawTransaction)
  • PSBT (v0. v2 & taproot is not yet.)
    • Create, Parse, Decode
    • Simple pubkey-hash sign / verify
    • Estimate Fee
    • Coin Selection (FundRawTransaction)
  • ECDSA Pubkey/Privkey (TweakAdd/Mul, Negate, Sign, Verify)
  • BIP32, BIP39
  • Output Descriptor (contains miniscript parser)
  • Schnorr/Taproot
  • Bitcoin Address (Segwit-v0, Segwit-v1, P2PKH/P2SH)
• Liquid Network
  • Confidential Transaction
    • Blind, Unblind
    • Reissuance
  • Confidential Address

Libraries for each language

• WebAssembly : cfd-js-wasm
  • JavaScript : cfd-js
  • C/C++ : cfd
    • Extend the cfd-core library. Defines the C language API and extension classes.
  • C++ : cfd-core
    • Core library. Definition base class.
• other language:
  • Python : cfd-python
  • C# : cfd-csharp
  • Go : cfd-go
  • Rust : cfd-rust

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Use case

use web page development

Copy the wasm file in the dist folder. For access to wasm, copy'cfdjs_wasm_json.js' or make your own. Copy cfdjs_wasm_jsonapi.js if necessary.

add dependencies on package.json (node.js or electron)

Add github's cfd-js-wasm path on caller app's package.json:

  "cfd-js-wasm": "github:cryptogarageinc/cfd-js-wasm#semver:^0.1.0",

If you use old npm or yarn, describe as follows:

  "cfd-js-wasm": "git+https://github.com/cryptogarageinc/cfd-js-wasm#semver:^0.1.0",

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for Developper

Dependencies

• Clang (10.0.0 or higher)
• C/C++ Compiler
  • can compile c++11
• CMake (3.14.3 or higher)
• Python (3.8 or higher)
• node.js (16.5 or higher)
• emscripten (1.39.10 or higher)

Build

Using docker

WebAssembly does not depend on the execution environment. You can use it in any environment by building it on Docker.

docker-compose build
docker-compose up

• attention If you get an error, do the following:
  1. remove external/libwally-core
  2. remove node_modules

local build

First, set the environment variable of emscripten according to the usage procedure of emscripten.

When using the cmake-js package and npm script, the options for compilation are already set.

npm install
npm run emcmake

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Test and Example

Test

npm run test

Example

web Example

Show github pages.

node.js Example

npm run example
npm run elements_example
npm run ts_example

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Information for developpers

using library

• cfd-js
  • cfd
    • cfd-core
      • libwally-core (forked from ElementsProject/libwally-core)
      • univalue (for JSON encoding and decoding)

formatter

• clang-format (using v10.0.0)
• eslint

linter

• cpplint
• eslint

document tool

• doxygen & graphviz

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Developper Note

Git connection:

Git repository connections default to HTTPS. However, depending on the connection settings of GitHub, you may only be able to connect via SSH. As a countermeasure, forcibly establish SSH connection by setting CFD_CMAKE_GIT_SSH=1 in the environment variable.

• Windows: (On the command line. Or set from the system setting screen.)

set CFD_CMAKE_GIT_SSH=1

• MacOS & Linux(Ubuntu):

export CFD_CMAKE_GIT_SSH=1

Ignore git update for CMake External Project:

Depending on your git environment, you may get the following error when checking out external:

  Performing update step for 'libwally-core-download'
  Current branch cmake_build is up to date.
  No stash entries found.
  No stash entries found.
  No stash entries found.
  CMake Error at /workspace/cfd-core/build/external/libwally-core/download/libwally-core-download-prefix/tmp/libwally-core-download-gitupdate.cmake:133 (message):


    Failed to unstash changes in:
    '/workspace/cfd-core/external/libwally-core/'.

    You will have to resolve the conflicts manually

This phenomenon is due to the git update related command. Please set an environment variable that skips update processing.

• Windows: (On the command line. Or set from the system setting screen.)

set CFD_CMAKE_GIT_SKIP_UPDATE=1

• MacOS & Linux(Ubuntu):

export CFD_CMAKE_GIT_SKIP_UPDATE=1

When using node.js 18 or higher

In node.js 18 or later, emscripten for cfd-js-wasm may not work correctly. In that case, you need to run it with the '--no-experimental-fetch' option.