Struct MigrationHistoryGraph 

pub struct MigrationHistoryGraph { /* private fields */ }

A validated DAG whose only node authority is a verified canonical manifest.

Implementations

impl MigrationHistoryGraph

pub fn from_verified( manifests: impl IntoIterator<Item = VerifiedSchemaMigrationManifest>, ) -> Result<Self, Diagnostic>

Build and validate a complete history graph from verified manifests only.

pub fn len(&self) -> usize

Return the number of verified history nodes.

pub fn is_empty(&self) -> bool

Return whether the history is empty.

pub fn manifest( &self, id: &MigrationId, ) -> Option<&VerifiedSchemaMigrationManifest>

Return one verified manifest by compound identity.

pub fn manifests( &self, ) -> impl ExactSizeIterator<Item = (&MigrationId, &VerifiedSchemaMigrationManifest)>

Iterate verified manifests in compound-identity order.

pub fn topological_order(&self) -> &[MigrationId]

Return deterministic topological order with compound-ID ready-node ties.

pub fn heads(&self) -> &[MigrationId]

Return every graph head in compound-identity order.

pub fn default_head(&self) -> Result<Option<&MigrationId>, Diagnostic>

Return the implicit default head, rejecting ambiguous multi-head history.

pub fn validate_applied( &self, applied: &BTreeSet<MigrationId>, ) -> Result<(), Diagnostic>

Require an applied set to contain every ancestor of every applied node.

pub fn applied_frontier( &self, applied: &BTreeSet<MigrationId>, ) -> Result<Vec<MigrationId>, Diagnostic>

Return maximal applied nodes, which form the applied reachability frontier.

pub fn plan_apply( &self, applied: &BTreeSet<MigrationId>, targets: &BTreeSet<MigrationId>, ) -> Result<Vec<MigrationId>, Diagnostic>

Plan the missing ancestor closure for explicit target nodes.

pub fn plan_apply_to_default_head( &self, applied: &BTreeSet<MigrationId>, ) -> Result<Vec<MigrationId>, Diagnostic>

Plan application to the sole implicit head.

pub fn plan_rollback( &self, applied: &BTreeSet<MigrationId>, removals: &BTreeSet<MigrationId>, ) -> Result<Vec<MigrationId>, Diagnostic>

Reverse-topologically order an explicit rollback set.

A node cannot be rolled back while any applied descendant remains.

Trait Implementations

impl Clone for MigrationHistoryGraph

fn clone(&self) -> MigrationHistoryGraph

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for MigrationHistoryGraph

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

Formats the value using the given formatter.

impl Eq for MigrationHistoryGraph

impl PartialEq for MigrationHistoryGraph

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

Equality operator ==.

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

Inequality operator !=.

impl StructuralPartialEq for MigrationHistoryGraph