Zcash transaction tool

The tool is designed to create and send Zcash transactions to a node (e.g., Zebra). Currently, it supports V5 transactions only.

The repo includes a simple Zebra docker image with a few changes to the original Zebra code to support the tool's test scenario.

Core components include:

1. librustzcash for transaction creation and serialization [Link]. Slightly modified with additional functionality.

2. Diesel ORM framework [Link]

3. Abscissa framework [Link]

Zebra node

Before testing, we need to bring up the desired node and ensure that V5 transactions are activated (NU5 is active).

Currently, we use a custom Zebra build. There are several changes compared to the upstream node:

• Activation height is set to 1,060,755

• PoW is disabled

• Consensus branch id is set to custom value. This is done to fork from the main chain

• Peers lists are empty, meaning that a node will not connect to any other nodes

• Blocks up to new activation height are pre-mined and stored in the database that is built into the docker image to avoid long initial sync time

To build and run the docker image:

docker build -t qedit/zebra-singlenode-txv5 .

docker run --name zebra-node -p 18232:18232 qedit/zebra-singlenode-txv5

More details on how the docker file is created and synced: Link

Configuration

The path to the configuration file can be specified with the --config flag when running the application. The default filename is "config.toml"

An example configuration file with default values can be found in example_config.toml

Build instructions

To set the Diesel database up:

1. Install diesel_cli: cargo install diesel_cli --no-default-features --features sqlite

2. Run migrations: diesel migration run

To build the application, run:

cargo build

Although release build is highly recommended for performance reasons:

cargo build --release

Main test scenario

Main test scenario (src/commands/test.rs) consists of the following steps:

1. Mine 100 empty blocks to be able to use transparent coinbase output
2. Create and mine a new shielding transaction with a transparent input and a shielded output
3. Create and mine a new transfer transaction with shielded inputs and outputs
4. Assert balances for the selected accounts

To run the test scenario:

cargo run --package zcash_tx_tool --bin zcash_tx_tool test

With optional, but recommended --release flag, or simply

zcash_tx_tool test

You can also run the tests using docker. To do that you'll need first to build the docker image

docker build -t zcash_tx_tool -f Dockerfile-demo .

And after that run the image itself. The default connection parameters are set to connect to the zebra-node running on the machine itself (127.0.0.1) If you ran the node in a docker container with the command above, you named that container "zebra-node", so you should use that as the ZCASH_NODE_ADDRESS. If the node is running on the ECS server, you can connect to it by setting the ZCASH_NODE_ADDRESS=.

First, make sure you created the network:

docker network create zcash-network

And started the node with the network argument, like this

docker run --name zebra-node --network zcash-network -p 18232:18232 qedit/zebra-singlenode-txv5

Here are the 3 options (No parameters will default to the first configuration)

docker run -it --network zcash-network -e ZCASH_NODE_ADDRESS=127.0.0.1 -e ZCASH_NODE_PORT=18232 -e ZCASH_NODE_PROTOCOL=http zcash_tx_tool
docker run -it --network zcash-network -e ZCASH_NODE_ADDRESS=zebra-node -e ZCASH_NODE_PORT=18232 -e ZCASH_NODE_PROTOCOL=http zcash_tx_tool
docker run -it --network zcash-network -e ZCASH_NODE_ADDRESS=<Domain> -e ZCASH_NODE_PORT=18232 -e ZCASH_NODE_PROTOCOL=http zcash_tx_tool

The '-it' parameter was added to allow the demo to be interactive.