Notes for developers

Making life easy for others

Write useful commit messages.

If your commit is changing a specific module in the code and not touching other parts of the codebase (as should be the case 99% of the time), consider writing a useful commit message that also mentions which module was changed.

For example, a message like:

added foo

is not as clear as

crypto/keypair: Added foo method for Bar struct.

Also keep in mind that commit messages can be longer than a single line, so use it to your advantage to explain your commit and intentions.

cargo fmt pre-commit hook

To ensure every contributor uses the same code style, make sure you run make fmt before committing. You can force yourself to do this by creating a git pre-commit hook like the following:

#!/bin/sh
if ! cargo +nightly fmt --all -- --check >/dev/null; then
    echo "There are some code style issues. Run 'make fmt' on repo root to fix it."
    exit 1
fi

exit 0

Inside the darkfi project repo, place this script in .git/hooks/pre-commit and make sure it's executable by running chmod +x .git/hooks/pre-commit.

Testing crate features

Our library heavily depends on cargo features. Currently there are more than 650 possible combinations of features to build the library. To ensure everything can always compile and works, we can use a helper for cargo called cargo hack.

The Makefile provided in the repository is already set up to use it, so it's enough to install cargo hack and run make check.

Etiquette

These are not hard and fast rules, but guidance for team members working together. This allows us to coordinate more effectively.

* once we have proper syncing implemented in ircd, these will become less relevant and not needed.

Another option is to run your ircd inside a persistent tmux session, and never miss messages.

Code coverage

You can run codecov tests of the codebase using cargo-llvm-cov:

$ cargo install cargo-llvm-cov
$ make coverage

You can then find the reports in target/llvm-cov/html/index.html

Static binary builds

Using LXC

Using musl-libc, we should be able to produce statically linked binaries from our codebase. A short setup using a Debian system and lxc can be the following:

Setup the LXC container:

# lxc-create -n xbuild-alpine -t alpine -- --release edge
# lxc-start -n xbuild-alpine
# lxc-attach -n xbuild-alpine

Inside the container, once attached, we have to install the required dependencies. We will have to use rustup to get the latest rust nightly, and we also have to compile sqlcipher on our own.

# apk add rustup git musl-dev make gcc openssl-dev openssl-libs-static tcl-dev zlib-static
# wget -O sqlcipher.tar.gz https://github.com/sqlcipher/sqlcipher/archive/refs/tags/v4.5.5.tar.gz
# tar xf sqlcipher.tar.gz
# cd sqlcipher-4.5.5
# ./configure --prefix=/usr/local --disable-shared --enable-static --enable-cross-thread-connections --enable-releasemode
# make -j$(nproc)
# make install
# cd ~
# rustup-init --default-toolchain nightly -y
# source ~/.cargo/env
# rustup target add wasm32-unknown-unknown --toolchain nightly

And now we should be able to build a statically linked binary:

# git clone https://github.com/darkrenaissance/darkfi -b master --depth 1
# cd darkfi
## Uncomment RUSTFLAGS in the main Makefile
# sed -e 's,^#RUSTFLAGS ,RUSTFLAGS ,' -i Makefile
# make darkirc

Native

In certain cases, it might also be possible to build natively by installing the musl toolchain:

$ rustup target add x86_64-unknown-linux-musl --toolchain nightly
## Uncomment RUSTFLAGS in the main Makefile
$ sed -e 's,^#RUSTFLAGS ,RUSTFLAGS ,' -i Makefile
$ make RUST_TARGET=x86_64-unknown-linux-musl darkirc