Struct Canonical

pub struct Canonical { /* private fields */ }

A collection of Dids and their Oids that is the tip for a given reference for that Did.

The general construction of Canonical is by using the Canonical::reference constructor. For the default branch of a Project, use Canonical::default_branch.

Canonical can then be used for performing calculations about the canonicity of the reference, most importantly the Canonical::quorum.

Implementations

impl Canonical

pub fn default_branch<S>( repo: &S, project: &Project, delegates: &NonEmpty<Did>, ) -> Result<Canonical, Error>

where S: ReadRepository,

Construct the set of canonical tips of the Project::default_branch for the given delegates.

pub fn reference<S>( repo: &S, delegates: &NonEmpty<Did>, name: &Qualified<'_>, ) -> Result<Canonical, Error>

where S: ReadRepository,

Construct the set of canonical tips given for the given delegates and the reference name.

pub fn tips(&self) -> impl Iterator<Item = (&Did, &Oid)>

Return the set of Dids and their Oid tip.

impl Canonical

pub fn modify_vote(&mut self, did: Did, new: Oid)

In some cases, we allow the vote to be modified. For example, when the did is pushing a new commit, we may want to see if the new commit will reach a quorum.

pub fn quorum( &self, threshold: usize, repo: &Repository, ) -> Result<Oid, QuorumError>

Computes the quorum or “canonical” tip based on the tips, of Canonical, and the threshold. This can be described as the latest commit that is included in at least threshold histories. In case there are multiple tips passing the threshold, and they are divergent, an error is returned.

Also returns an error if heads is empty or threshold cannot be satisified with the number of heads given.