Struct PolicyChain 

pub struct PolicyChain { /* private fields */ }

An ordered, validated list of NamespacePolicy versions for one namespace.

The chain enforces immutability-by-versioning and only-legal-strengthening migration (see PolicyChain::push). Each version n owns the half-open validity range [effective_from_n, effective_from_{n+1}); PolicyChain::active_at resolves the policy in force at a tree position.

Implementations

impl PolicyChain

pub fn genesis(policy: NamespacePolicy) -> Result<Self>

Start a chain from a genesis policy.

Errors

Returns Error::PolicyMigrationRejected if the policy is not a valid genesis (it must have prev_policy_hash == None).

pub fn versions(&self) -> &[NamespacePolicy]

The ordered policy versions.

pub fn latest(&self) -> &NamespacePolicy

The most recent (currently active) policy version.

pub fn push(&mut self, next: NamespacePolicy) -> Result<()>

Append a migration to the chain, enforcing the #324 rules:

• same namespace;
• policy_schema_version is exactly prev + 1;
• effective_from is strictly greater than the prior version’s;
• prev_policy_hash equals the prior version’s NamespacePolicy::policy_hash;
• the migration does not weaken posture (security level, commitment hash, or VRF mode may only stay the same or strengthen).

Errors

Returns Error::PolicyMigrationRejected for any rule violation.

pub fn active_at(&self, position: u64) -> Result<&NamespacePolicy>

Resolve the policy version in force at tree position: the version whose half-open range [effective_from_n, effective_from_{n+1}) contains it.

Errors

Returns Error::UnknownNamespacePolicy if position precedes the genesis effective_from (no version was yet in force).

Trait Implementations

impl Clone for PolicyChain

fn clone(&self) -> PolicyChain

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for PolicyChain

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Eq for PolicyChain

impl PartialEq for PolicyChain

fn eq(&self, other: &PolicyChain) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl StructuralPartialEq for PolicyChain