Perun CKB Demo

This repository contains the CKB demo client, which utilizes the go-perun channel library.

Usage

Dependencies

We use various tools to enable a convenient setup for the local development testnet. If you want to use our setup-devnet.sh script, make sure the following commandline tools are installed:

• jq:
  • Used to parse and edit some configuration files.
• sed and awk:
  • We modify some fields of the files generated by the ckb init --chain dev command using sed and awk.
• tmux and tmuxp:
  • tmuxp is a session manager for tmux that allows to easily create descriptive .yaml configuration files to create and attach to tmux sessions.
• expect:
  • We completely automize the process for test-wallet creation, deploying of contracts etc. To make this work reliably, we use expect which allows to describe how a commandline application is fed input.
• make:
  • Not strictly necessary, but it should be available on most systems by default. In case you do not want to install make check out the Makefile content and issue the command on your own.
• ckb with version 0.109.0 or higher.
• ckb-cli with version 1.4.0 or higher.
• capsule with version 0.9.2.
• docker and a running dockerd instance!

Setup

Clone this repository:

  $ git clone git@github.com:perun-network/perun-ckb-demo

Initiliaze git submodules and make sure all dependencies are installed.

  $ cd perun-ckb-demo
  $ git submodule update --init --recursive

Build the demo client:

  $ go build -o perun-ckb-demo

Spin up the local testnet. For this change to the perun-ckb-demo/devnet directory and issue the make dev command. NOTE: Make sure you are in a terminal that is not already running within tmux. make dev will use this terminal window and create a tmux session.

  $ cd ./devnet
  $ make dev

Wait for ~15 seconds. This is the time it takes for the devnet setup to be completed (deployed all contracts, funded testnet accounts etc.).

Using the demo

If you are comfortable using tmux you can of course use the devnet session, otherwise in a new terminal window start the perun-ckb-demo. NOTE: Make sure you are in the root directory of the perun-ckb-demo repository.

  $ cd perun-ckb-demo/
  $ ./perun-ckb-demo

You will be greeted with a demo window that is split into two panes:

Keybinds

• ctrl+a: Select left pane
• ctrl+b: Select right pane
• tab: Cycle through selectable fields
• Enter: Select or confirm highlighted field
• r: Go back to parent page
• q: Close the demo

Example run

Let's use the left side for Alice and the right side for Bob:

We will use Bob to view the channels he has currently open with others and Alice to open a new channel with Bob.

We will use Alice to open a channel with 400 CKBytes.

After issuing the open transaction, we have to wait for it to be confirmed on-chain. Both parties will wait:

After a few seconds the transaction is confirmed on-chain and both parties were able to observe that fact. This will result in both Alice and Bob viewing the now offically established channel.

Let's use Alice to send ten micropayments of 20 CKBytes per payment to Bob via their channel.

We can observe the fact that multiple payments were issued by looking at the channels version number, which was incremented by ten, the amount of micropayments issued by Alice.

Now we use Bob to settle the channel.

After a few seconds the channels settlement is confirmed on-chain and we can view the updated balances for Bob and Alice.