In order to follow along with the examples and complete the lab exercises, some basic software and tooling will need to be installed on your computer.
Our examples are all created using a Linux environment, and this is the preferred environment for development on Nervos in general. It should also work for MacOS and Windows, but there may be a few extra steps you will need to take to get things working.
Our lessons and lab exercises all rely on Node.js v18 LTS, so this will need to be installed prior to starting. We officially support and test only with this exact version. If you experience any problems, please make sure you are using the correct version of Node.js.
Installing vanilla Node.js is fine or you can use a tool like NVM to manage the installation. Many developers prefer using NVM since it allows you to quickly select between different versions of Node.js without having to reinstall.
- Vanilla Node.js (All Platforms): https://nodejs.org/en/download/
- NVM (Linux & MacOS): https://github.com/nvm-sh/nvm
- NVM (Windows): https://github.com/coreybutler/nvm-windows
We will be using the Rust programming language to create on-chain scripts and install the required tooling. Using rustup is generally recommended, but there are several methods available.
- Rust (All Platforms): https://www.rust-lang.org/tools/install
You will need Git to clone the example code and lab exercises from GitHub in order to complete each lesson. Using your favorite Git client is fine.
- Git (All Platforms): https://git-scm.com/downloads
Use the command below to clone the Developer Training Course materials, which includes the example code and lab exercises we will use in the lessons.
git clone https://github.com/jordanmack/developer-training-course.git
Then enter the directory and install the Node.js dependencies.
cd developer-training-course
npm iWhile installing dependencies using npm i you may get some warnings. This is normal and does not always indicate a problem. If you encounter errors, make sure you are on the correct version of Node.js by using the command node -v.
You will need to have a CKB Dev Blockchain node running locally for our code to interact with. This is a full Nervos CKB node that will run on your computer with a private testnet, also known as a devnet.
You will need to complete the setup instruction from the URL below for the sections "Setup a Dummy-Worker Blockchain" and "Adding the Genesis Issued Cells".
- CKB Dev Blockchain Setup Instructions: https://docs.nervos.org/docs/basics/guides/devchain
Alternatively, if you are using an OS with a GUI you can use Tippy to create a one-click devnet.
- Tippy One-Click Devnet CKB Node Tool: https://github.com/nervosnetwork/tippy
After you have created your devnet, you will need to copy some of the chain configuration values into the developer-training-course repo. The scripts we will be using require this information about the devnet in order to locate resources to create transactions properly.
From the console, enter the directory where you have your devnet CKB Node, and run the following command.
./ckb list-hashes
This should give you console output similar to the following.
The system cell hashes are specifically the ones we are interested in. These describe the locations of resources the Developer Training Course will need. You will need to copy these values into the file developer-training-course/config.json in the correct locations. This config.json file will be used by the Lumos framework in the later lessons to create transactions.
The table below describes the values that need to be updated in config.json, and where they come from the output from ./ckb list-hashes. The format of config.json and the output of ./ckb list-hashes are structured differently, so you will need to match them up manually.
For example, the SECP256K1_BLAKE160 key in config.json corresponds with the config group that contains the line included_cells = ["Bundled(specs/cells/secp256k1_data)", "Bundled(specs/cells/secp256k1_blake160_sighash_all)"]. The values for SECP256K1_BLAKE160.TX_HASH and SECP256K1_BLAKE160.INDEX are contained in the lines directly underneath.
| config.json | ckb list-hashes |
|---|---|
| SECP256K1_BLAKE160 | Bundled(specs/cells/secp256k1_blake160_sighash_all) |
| SECP256K1_BLAKE160.TX_HASH | tx_hash |
| SECP256K1_BLAKE160.INDEX | index |
| SECP256K1_BLAKE160_MULTISIG | Bundled(specs/cells/secp256k1_blake160_multisig_all) |
| SECP256K1_BLAKE160_MULTISIG.TX_HASH | tx_hash |
| SECP256K1_BLAKE160_MULTISIG.INDEX | index |
| DAO | Bundled(specs/cells/dao) |
| DAO.TX_HASH | tx_hash |
| DAO.INDEX | index |
A total of six values should be updated in total. This process only needs to be done once, but if you set up a new dev chain, you will need to repeat this process since the values will be different.