Vade Evan

About

This crate allows you to use to work with DIDs and zero knowledge proof VCs. It offers a command line interface and support to build package for C, Java, WASM, and exports a VadeEvan API to use the same functionalities in other Rust projects.

Compiling vade-evan

"Regular" build

No surprise here:

cargo build --release

Default Features

By default features did-sidetree, did-substrate, didcomm, jwt-vc, vc-zkp-bbs, cli are used, so a default feature bundle is used and compiled to a command line interface, so basically using the default feature setup (like above) builds the same as:

cargo build --release --no-default-features --features did-sidetree, did-substrate, didcomm, jwt-vc, vc-zkp-bbs, cli

When building vade-evan, you usually use target- feature, which means that you want to include a certain set of features and want to make it available for a certain target/platform.

Targets

Targets define for which platform you want to build a vade package. Also more building for more than one target is not supported. Currently these targets are available:

• target-c-sdk - build for usage in IN3 SDK with request list

cargo build --release --no-default-features --features target-c-sdk

• target-c-lib - build for usage in C

cargo build --release --no-default-features --features target-c-lib

• target-cli - build command line interface --> ./target/release/vade_evan_cli

cargo build --release --no-default-features --features target-cli

• target-java-lib - build for usage in Java

cargo build --release --no-default-features --features target-java-lib

• target-wasm - in combination with wasm-pack, build for usage in WASM (see below)

wasm-pack build --release --target nodejs -- --no-default-features --features target-wasm

One (and only one) target must be provided when building without default features.

About the builds

C builds with sdk feature

Features can be adjusted to support integration with IN3 SDK by enabling target-c-sdk feature. target-c-sdk feature enables HTTP request/response managed via IN3 SDK.

cargo build --release --no-default-features --features target-c-sdk

Limitations of target-c-sdk feature

target-c-sdk feature can't be used with target-wasm, target-java-lib and target-cli as in3 sdk specific request list pointers are integrated only with target-c-sdk as parameters in c-lib interface. If someone has specific need to use sdk request list pointers with targets other than target-c-sdk, it will have to be done separately by editing wasm or java interfaces.

WASM

WASM pack

To compile vade-evan for wasm, use wasm-pack, you can specify whether to build a browser or a nodejs environment with wasm-pack's --target argument. Also use the target-wasm feature to tell the compile how to configure vade-evan for the vade build.

nodejs:

wasm-pack build --release --target nodejs -- --no-default-features --features target-wasm

browser:

wasm-pack build --release --target web -- --no-default-features --features target-wasm

Wrapper for WASM pack

A project that wraps calls against the WASM file has been added and placed at builds/wasm.

To build it, you need to have to build vade-evan as described above, navigate to builds/wasm and call

yarn && yarn build

If you want to try it out, navigate to builds/wasm/example and run

yarn && node index.js

This example will generate a new DID, assign a document to it and update it afterwards.

Features

Feature name schema

Features in this project follow a naming schema that looks as following:

• target- features decide which build target (CLI, WASM, SDK, etc.) to build for

target- features are intended to be used for build/run commands. Others should only be used from within Cargo.toml to allow including functionalities in the source files.

Feature overview

feature	default	contents
target-c-sdk		build for usage in SDK request_list
target-c-lib		build for usage in C
target-cli	x	build command line interface
target-java-lib		build for usage in Java
target-wasm		build for usage in WASM
did-sidetree	x	add support for using sidetree DIDs
did-substrate	x	add support for using substrate DIDs
didcomm	x	add DIDComm support
jwt-vc	x	add support for JWT VCs
vc-zkp-bbs	x	add support for BBS VCs

Dependencies

At the moment all vade related dependencies (vade itself and its plugins) are supposed to be pulled from the latest commit of the develop branch. As the dependency handling stores the hash of this commit in the lock file, updates on develop branch are not used by default.

If those updates should be pulled, the entry in the Cargo.lock file has to be deleted and cargo build has to be run again to update these hashes. If wanting to update specific dependencies, those can be deleted from the Cargo.lock by hand. If wanting to update all of the vade related dependencies, a script (scripts/remove-vade-dependencies-from-lockfile.sh) can be used. Note that this script relies on dasel so this must be installed locally, e.g. with homebrew.