TVL Code Reviews

Table of Contents

TVL Code Reviews

This document describes the TVL code review process & tooling. If you are looking for general contribution guidelines, please look at the general contribution guidelines.

All changes are tracked at cl.tvl.fyi using Gerrit. See Registration for information on how to register an account.

Gerrit setup

Gerrit uses the concept of change IDs to track commits across rebases and other operations that might change their hashes, and link them to unique changes in Gerrit.

To make this process smooth for users, the repository should be cloned and a commit hook should be installed as follows:

git clone "ssh://$USER@code.tvl.fyi:29418/depot"
scp -p -P 29418 $USER@code.tvl.fyi:hooks/commit-msg "depot/.git/hooks/"

If you have a previous clone of the depot via HTTP you can use git remote set-url to update the origin URL and install the hook in the same way as above.

Gerrit workflows

The developer workflow on Gerrit is quite different from what GitHub-users are used to.

The depot does not have branches (other than Gerrit's internal metadata refs) and all development happens at HEAD.

Every time you create a new commit the change hook will insert a unique Change-Id tag into the commit message. Once you are satisfied with the state of your commit and want to submit it for review, you push it to a git ref called refs/for/master. This designates the commits as changelists (CLs) targeted for the master branch.

Example:
git commit -m 'docs(REVIEWS): Fixed all the errors in the reviews docs'
git push origin HEAD:refs/for/master

TIP: Every individual commit will become a separate change. We do not merge related commits, but instead submit them one by one. Be aware that if you are expecting a different behaviour and attempt something like an unsquashed subtree merge, you will produce a lot of CLs. This is strongly discouraged.

During your review, the reviewer(s) might ask you to make changes. You can simply amend your commit(s) and push to the same ref. Gerrit will automatically update your changes.

Read more about the Gerrit workflow in the Gerrit walkthrough.

Review process & approvals

Each user has the ability to create their own users directory in //users/<username> in which they can submit code without review from other contributors (they will still need to +2 their own changes, and the initial check-in of the OWNERS file needs to be reviewed).

You can set a directory like this up for yourself by proposing a change similar to CL/246.

For all paths outside of //users, code review is required. We have no strict guidelines about the review process itself, as we're not a megacorp, but we have formalised checks before submitting:

At least one person who is an owner of the codepath must have given a +2 review
The commit message must conform to our guidelines
No code review comments must be left unresolved

If all these conditions are fulfilled, the change author submits their change themselves.

Registration

If you would like to have an account on the Gerrit instance, follow these instructions:

Be a member of ##tvl.
Clone the depot locally.
Create a user entry in our LDAP server in tvl-slapd/default.nix. You can create your password hash by using slappasswd, which ships in the openldap package on most distributions.

On systems with Nix systems you can use nix-shell -p openldap to get access to the command.
Create a commit adding yourself (see e.g. CL/223).
Submit the commit via email (see below).

Submitting changes via email

You can submit a patch via email to depot@tazj.in and it will be added to Gerrit by a contributor.

Create an appropriate commit locally and send it us using either of these options:

git format-patch: This will create a .patch file which you should email to us.
git send-email: If configured on your system, this will take care of the whole emailing process for you.

The email address is a public group.