ofborg/README.md
Richard Marko a2446b4ea1 README: add Hacking section
Co-Authored-By: Cole Helbling <cole.e.helbling@outlook.com>
2020-05-20 10:20:07 -07:00

8.2 KiB

grahamcofborg

Guidelines

  1. make sure you've reviewed the code before you trigger it on a PR that isn't your own
  2. be gentle, preferably don't run mass rebuilds / massive builds like chromium on it

Automatic Building

Users who are trusted or known (see: Trusted Users vs Known Users) will have their PRs automatically trigger builds if their commits follow the well-defined format of Nixpkgs. Specifically: prefixing the commit title with the package attribute. This includes package bumps as well as other changes.

Example messages and the builds:

Message Automatic Build
vim: 1.0.0 -> 2.0.0 vim
vagrant: Fix dependencies for version 2.0.2 vagrant
python36Packages.requests,python27Packages.requests: 1.0.0 -> 2.0.0 python36Packages.requests, python27Packages.requests
python{2,3}Packages.requests: 1.0.0 -> 2.0.0 nothing

If a PR is opened with many commits, it will create a single build job for all of the detected packages. If a PR is opened and many commits are pushed one by one to the open PR, many build jobs will be created.

To disable automatic building of packages on a PR, add [WIP] to the PR's title, or the 2.status: work-in-progress label.

Commands

The comment parser is line-based, so comments can be interleaved with instructions.

  1. To trigger the bot, the line must start with a case insensitive version of @GrahamcOfBorg.
  2. To use multiple commands, insert a bit of whitespace and then your new command.

Commands:

test (added: 2017-11-24)

@grahamcofborg test list of tests

This will run nix-build ./nixos/release.nix -A tests.list -A tests.of -A tests.tests in the nixpkgs checkout. Note: this will only run on x86_64-linux machines.

eval

@grahamcofborg eval

Note: Every PR automatically evaluates when it is opened and when the commits change. There is no reason to run eval on a PR unless the evaluation has failed for weird reasons, or because master was broken before.

build

@grahamcofborg build list of attrs

This will run nix-build ./default.nix -A list -A of -A attrs in the nixpkgs checkout.


Multiple Commands:

@grahamcofborg build list of attrs
@grahamcofborg eval

or even:

@grahamcofborg build list of attrs @grahamcofborg eval

This will also work:

looks good to me!
@grahamcofborg build list of attrs

And this is fine:

@grahamcofborg build list of attrs
looks good to me!

This is will build list, of, attrs, looks, good, to, me!:

@grahamcofborg build list of attrs looks good to me!

Trusted Users vs Known Users

Known users have their builds executed on platforms with working sandboxing. At the time of writing, that means:

  • x86_64-linux
  • aarch64_linux

Trusted users have their builds executed on all platforms, even if they don't have good sandboxing. This opens the host up to a higher risk of security issues, so only well known, trusted member of the community should be added to the trusted user list.

At the time of writing, trusted users have their builds run on the following platforms:

  • x86_64-linux
  • aarch64_linux
  • x86_64-darwin

See ./config.public.json and ./config.known-users.json for a list of all the trusted and known users.

How does OfBorg call nix-build?

Builds are run like:

HOME=/homeless-shelter NIX_PATH=nixpkgs=$(pwd) nix-build ./default.nix --no-out-link --keep-going -A hello --option restrict-eval true --option build-timeout 1800 --argstr system thesystem --show-trace

How does OfBorg call nix-instantiate?

NixOS evals are run like:

HOME=/homeless-shelter NIX_PATH=nixpkgs=$(pwd) nix-instantiate ./nixos/release.nix -A manual --option restrict-eval true --option build-timeout 1800 --argstr system thesystem --show-trace

Nixpkgs evals are run like:

HOME=/homeless-shelter NIX_PATH=nixpkgs=$(pwd) nix-instantiate ./pkgs/top-level/release.nix -A manual --option restrict-eval true --option build-timeout 1800 --argstr system thesystem --show-trace

Running meta checks locally

$ curl -o outpaths.nix https://raw.githubusercontent.com/NixOS/ofborg/released/ofborg/src/outpaths.nix
$ GC_INITIAL_HEAP_SIZE=4g nix-env -f ./outpaths.nix -qaP --no-name --out-path --arg checkMeta true > out-paths

Running a builder

It is recommended to create a special user for the ofBorg operation. This user should have git configuration for default username/email for non-interactive merges. For example:

git config --global user.email "graham+cofborg@example.com"
git config --global user.name "GrahamCOfBorg"
nix-shell ./shell.nix
$ cd ofborg
$ cargo build
cargo build

then copy example.config.json to config.json and edit its vars. Set nix.remote to an empty string if you're not using the daemon.

Run

./target/debug/builder ./config.json

Note the config.public.json for the public pieces of how I run ofborg, which is merged with config.known-users.json and a third private config file of credentials. These files contain some special keys like

  • known users
  • authorized users
  • log storage

they are only used in the backend processing tasks, and there is no need for them on builders. However, to update the list in config.known-users.json, run ./scripts/update-known-users.sh.

In case you have a non-trivial setup on Linux, make sure that the ofborg user has access to dev/kvm, as it is needed for running tests.

If you want to run multiple builder instances on the same physical machine please make sure they use different configs with different instance identity (same username/password is OK) and different repository paths. Running two builders with the same config risks data corruption.

See also: https://github.com/NixOS/ofborg/wiki/Operating-a-Builder

Hacking

$ git clone https://github.com/NixOS/ofborg/
$ cd ofborg
$ nix-shell ./shell.nix
$ cd ofborg # enter the subdirectory with Rust code
# make your changes
$ cargo build
$ cargo check
$ cargo test

To test whether or not Continuous Integration will pass with your changes, you can run the following commands from the root of your checkout:

$ nix-shell --run checkPhase -A mozilla-rust-overlay # checks rustfmt and clippy
$ nix-shell --run checkPhase # runs the test suite
$ nix-build -A ofborg.rs # build ofborg

Currently there is no easy way to set up a test instance of ofborg. If cargo check and cargo test both succeed, feel free to Pull Request your changes. Make sure to format your code with cargo fmt and check for additional warnings with cargo clippy. If you added, removed, or updated the dependencies, also be sure to update Carnix by running ./nix/update-carnix.sh.

To disable warnings as errors, run your command with an empty RUSTFLAGS. For example:

$ RUSTFLAGS= cargo clippy

This will override the default of -D warnings set in shell.nix, which tells Rust to error if it detects any warnings.

old php stuff...

Only Graham needs to do this, since I run the only remaining PHP components.

<?php

require_once __DIR__ . '/vendor/autoload.php';
use PhpAmqpLib\Connection\AMQPSSLConnection;
use PhpAmqpLib\Message\AMQPMessage;

function rabbitmq_conn($timeout = 3) {
    $host = 'events.nix.gsc.io';
    $connection = new AMQPSSLConnection(
        $host, 5671,
        'eventsuser, eventspassword, '/',
        array(
            'verify_peer' => true,
            'verify_peer_name' => true,
            'peer_name' => $host,
            'verify_depth' => 10,
            'ca_file' => '/etc/ssl/certs/ca-certificates.crt',
        ), array(
            'connection_timeout' => $timeout,
        )
    );

    return $connection;
}

function gh_secret() {
    return "github webhook secret";
}