Struct Capabilities 

pub struct Capabilities {
    pub schema_introspection: bool,
    pub stable_paging: bool,
    pub nested_source_paths: bool,
    pub writable: bool,
    pub transactional_batch: bool,
    pub resumable_cursor: bool,
}

Capabilities : What a migration connector declares it can do. The engine consults this before it starts, so an unsupported operation is refused up front instead of failing part-way through a run. Every field defaults to false for a connector that has not declared it – an absent capability always reads as "no", never as an optimistic "yes". There is deliberately no per-field "unknown" state: unlike a write-permission probe (which can genuinely fail at runtime, and where the engine branches on the difference), a capability is a static statement a connector makes about itself, and "not declared" and "cannot" produce identical behaviour. Per connection, not per connector type – two instances of the same connector may answer differently (a DuckDB store over Parquet has a schema, one over a headerless CSV does not).

Fields

schema_introspection: bool

The connector can enumerate a dataset’s columns authoritatively. false means it has no schema authority at all (a headerless CSV, a schema-less collection) – not that the dataset is missing; the mapping is then reported as unvalidated (a warning) rather than as every field being absent.

stable_paging: bool

The connector can page a dataset by a unique, total order, so batches are a stable partition with no skipped or duplicated rows. false makes it unusable as a source and blocks the run. Whether one particular table has such a key (e.g. a primary key) is a separate, per-table runtime error.

nested_source_paths: bool

The connector can resolve a dotted ColumnMapping.source_column (profile.address.city), not just a top-level name. A relational connector declares false, and any nested mapping entry is then an Error-severity issue naming the offending path.

writable: bool

The connector can be a migration target at all. false is what "this target is read-only" is read from – distinct from the per-table, per-connection question of whether the current role holds INSERT, which is probed separately and reported through MappingReport.

transactional_batch: bool

A batch is applied atomically – all rows or none. false does not block a run, but is warned about: a failure can leave a partially applied batch to reconcile by hand.

resumable_cursor: bool

The connector’s page cursor is durable across a process restart. This is only the connector half of checkpoint/resume; the engine does not persist run state yet, so no run is resumable today regardless of this value. The dry-run report says which half is missing.

Implementations

impl Capabilities

pub fn new( schema_introspection: bool, stable_paging: bool, nested_source_paths: bool, writable: bool, transactional_batch: bool, resumable_cursor: bool, ) -> Capabilities

What a migration connector declares it can do. The engine consults this before it starts, so an unsupported operation is refused up front instead of failing part-way through a run. Every field defaults to false for a connector that has not declared it – an absent capability always reads as "no", never as an optimistic "yes". There is deliberately no per-field "unknown" state: unlike a write-permission probe (which can genuinely fail at runtime, and where the engine branches on the difference), a capability is a static statement a connector makes about itself, and "not declared" and "cannot" produce identical behaviour. Per connection, not per connector type – two instances of the same connector may answer differently (a DuckDB store over Parquet has a schema, one over a headerless CSV does not).

Trait Implementations

impl Clone for Capabilities

fn clone(&self) -> Capabilities

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for Capabilities

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

Formats the value using the given formatter.

impl Default for Capabilities

fn default() -> Capabilities

Returns the “default value” for a type.

impl<'de> Deserialize<'de> for Capabilities

fn deserialize<__D>(__deserializer: __D) -> Result<Self, __D::Error>

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl PartialEq for Capabilities

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

Equality operator ==.

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

Inequality operator !=.

impl Serialize for Capabilities

fn serialize<__S>(&self, __serializer: __S) -> Result<__S::Ok, __S::Error>

where __S: Serializer,

Serialize this value into the given Serde serializer.

impl StructuralPartialEq for Capabilities