Requirements: Setup
Install Nix
You need the nix-shell to build the exercises and run the tests. And to get the nix-shell you need to install the nix package manager.
Linux
To install the package manager you run this command:
sh <(curl -L https://nixos.org/nix/install)
. ~/.nix-profile/etc/profile.d/nix.sh
nix-env -iA cachix -f https://cachix.org/api/v1/install
cachix use holochain-ci
The above commands will also setup your current shell, and the cachix cache so that Holochain builds are cached.
Windows
Native development on Windows is not supported at the moment. But if you run Linux using WSL2 or a VM you can use the Linux instructions.
MacOS
Make sure you have the XCode Developer Tools installed, then on
macOS 10.15 Catalina and later
sh <(curl -L https://nixos.org/nix/install) --darwin-use-unencrypted-nix-store-volume
. ~/.nix-profile/etc/profile.d/nix.sh
nix-env -iA cachix -f https://cachix.org/api/v1/install
cachix use holochain-ci
The above commands will also setup your current shell, and the cachix cache so that Holochain builds are cached.
macOS 10.14 Mojave and earlier
sh <(curl -L https://nixos.org/nix/install)
. ~/.nix-profile/etc/profile.d/nix.sh
nix-env -iA cachix -f https://cachix.org/api/v1/install
cachix use holochain-ci
The above commands will also setup your current shell, and the cachix cache so that Holochain builds are cached.
Clone repo
The next step is to clone the github repository.
git clone https://github.com/holochain-gym/developer-exercises.git
After that jump in to the base folder of the repository
cd developer-exercises
Check
Before diving into the nix-shell, you should check if everything is setup correct.
Check if nix-shell is installed correctly:
nix-shell --version
This should print out the version of the nix-shell.
Next check if you have a default.nix file in the base folder of the cloned repository.
ls default.nix
Nix-shell
Now you are about to run the nix-shell command. This command will look for a default.nix file and build a complete development environment with all the necessary tools and dependencies with all the right versions.
So go ahead and run:
nix-shell
npm install
Running nix-shell for the first time will take a few minutes, after that it will take just seconds.
Try it... You exit the nix shell like any other shell: type exit or press Ctrl+C. Then run nix-shell again.
Among some of the thing that nix-shell install is a tool called hn-introspect. It helps to inspect which version of holochain, HDK and its dependencies are installed. Look at this example:
$ hn-introspect
List of applications and their version information
main
- hc-0.0.19: https://github.com/holochain/holochain/tree/8a0cd9283fd881ddbc467b1d0d97ee2fcd49d992
- holochain-0.0.118: https://github.com/holochain/holochain/tree/8a0cd9283fd881ddbc467b1d0d97ee2fcd49d992
- kitsune-p2p-proxy-0.0.14: https://github.com/holochain/holochain/tree/8a0cd9283fd881ddbc467b1d0d97ee2fcd49d992
- lair-keystore-0.0.9: https://github.com/holochain/lair/tree/v0.0.9
- rustc: rustc 1.55.0 (c8dfcfe04 2021-09-06)
- cargo fmt: rustfmt 1.4.37-stable (c8dfcfe 2021-09-06)
- cargo clippy: clippy 0.1.55 (c8dfcfe 2021-09-06)
- perf: perf version 5.10.81
If you want to know about the Holochain development environment, you can read a bit more about why the Holochain projects use Nix in the article here.
Devtools
We recommend using VSCode with the rust-analyzer extension while coding rust.
Start
Next up you have 3 options:
- If you don't know much about core concepts of Holochain, you can check out the docs section to start reading up. Or if you want a more hands-on approach start in the Concepts section of our gym.
- If you are new to Rust you can look here to find out what you need to learn and where you can learn it
- If you are ready to start the first exercise, it is a good idea to read about the anatomy of an exercise, so you understand the folder structure and specific files. After that jump right in to the first exercise. You can access all the exercises in the menu at the left. Every exercise will have some kind of interactive playground, some documentation or sample code and instructions. Each exercise has its own README file. It will tell you how to build the exercises and run the tests.