Zcash Docker Development Environment

🛑 This is a work-in-progress and may not function reliably. It is certainly not intended to be used in production. 🛑

This repository contains a Dockerfile that will help you get started building Zcash's mobile app wallet stack. The projects' code is kept on your host filesystem and shared into the docker container, so you can keep using the editors and tools you're familiar with, and only use the container to run builds. You can also run the zcashd and lightwalletd services within the container.

The development environment currently supports building:

• zcashd
• librustzcash (preview branch)
• lightwalletd (preview branch)
• zcash-android-wallet-sdk (preview branch)
• zcash-android-wallet-poc

Quick Start

Requirements: Docker, 30GB free disk space.

First, checkout this repository:

git checkout <this-repository's-url>
cd zdev-docker

Next, build the Docker image. This will create an image called zdev which has all of the build dependencies pre-installed:

docker build -t zdev docker

Now, clone all of the projects you want to work on into the mount/ directory:

cd mount
git clone git@github.com:zcash/zcash.git
git clone git@github.com:zcash-hackworks/lightwalletd.git
git clone git@github.com:str4d/librustzcash.git --branch preview
git clone git@github.com:zcash/zcash-android-wallet-sdk.git --branch preview
git clone git@github.com:zcash/zcash-android-wallet-poc.git
cd ..

You can now launch a new container instance of zdev and have access to your clones of zcash, lightwalletd, etc. from within:

docker run -it --mount type=bind,source="$(pwd)"/mount,target=/mount zdev

The ./mount directory will be shared between the host and the container, accessible in the container at /mount. The changes you make to files inside /mount in the container will change the files in ./mount.

The previous command opened a shell inside the container. You can run build commands, for example:

cd /mount/zcash
./zcutil/build.sh -j$(nproc)
./zcutil/fetch-params.sh
./qa/zcash/full-test-suite.py

See the individual projects' documentation for build instructions.

To open another shell into the running container, run docker container ls, copy the container ID, and then run docker exec -it <container ID> bash. You can start and stop the container with docker start and docker stop.

To update the Ubuntu packages in the zdev image or make changes to which dependencies are installed, edit the docker/install-build-dependencies.sh script and then re-build the zdev image using the same command as above. The changes will take effect in the next new container instance you launch. You can of course also just make changes directly to the container instead of updating the image every time.

Build Cheat Sheet

Note: All of the builds are independent for now, i.e. the build output of librustzcash doesn't get used as an input to the zcash-android-wallet-sdk build.

zcashd

cd /mount/zcash
./zcutil/build.sh -j$(nproc)

librustzcash

cd /mount/librustzcash
cargo build --release

lightwalletd

cd /mount/lightwalletd
go run cmd/injest/main.go <...>
go run cmd/server/main.go <...>

zcash-android-wallet-sdk

cd /mount/zcash-android-wallet-sdk
./gradlew clean assembleZcashtestnetRelease

zcash-android-wallet-poc

cd /mount/zcash-android-wallet-poc cd zcash-android-wallet-app ./gradlew clean assembleZcashtestnetDebug

Running the Stack

This section will help you set up:

1. A zcashd node connected to testnet.
2. A lightwalletd injestor which receives blocks from the zcashd node.
3. A lightwalletd server which serves the blocks parsed by the injestor to light clients.

First, start the lightwalletd injestor:

cd /mount/lightwalletd
go run cmd/ingest/main.go -db-path database.db -log-file injestor-log.txt

This will listen on port 28332 for a ZMQ connection from zcashd. Now put the following contents in /root/.zcash/zcash.conf:

testnet=1
addnode=testnet.z.cash
zmqpubcheckedblock=tcp://127.0.0.1:28332
rpcuser=yourusername
rpcpassword=yourpassword

You're advised to change yourusername and yourpassword to something random. This configures zcashd to sync with the testnet and send blocks to lightwalletd on localhost port 28332. Now build and run zcashd:

cd /mount/zcash
./zcutil/build.sh -j$(nproc)
./zcutil/fetch-params.sh
./src/zcashd

If you check the contents of /mount/lighwalletd/injestor-log.txt, you should see that it is receiving blocks as the zcashd node syncs.

To serve these blocks to light clients, start the server:

cd /mount/lightwalletd
go run cmd/server/main.go -conf-file /root/.zcash/zcash.conf -db-path database.db -log-file server-log.txt

Note: If this command fails and there's an error message about database locks in server-log.txt you need to stop the injestor, start the server, then re-start the injestor.

TODOs

• Verify the "running the stack" instructions are actually correct.
• Finish instructions for building & connecting the app.
• Put .zcash-params in the image.
• Put .zcash-mainnet and .zcash-testnet fully loaded into the image.
• Make the builds use the output of dependencies' builds
• Security review (are tools/code being downloaded safely? etc)