Struct DatabaseEntityResolver 

pub struct DatabaseEntityResolver<A: DatabaseAdapter> { /* private fields */ }

Resolves federation entities from local databases.

Implementations

impl<A: DatabaseAdapter> DatabaseEntityResolver<A>

pub fn new(adapter: Arc<A>, metadata: FederationMetadata) -> Self

Create a new database entity resolver.

pub async fn resolve_entities_from_db( &self, typename: &str, representations: &[EntityRepresentation], selection: &FieldSelection, ) -> Result<Vec<Option<Value>>>

Resolve entities from database.

Arguments

• typename - The entity type name (e.g., “User”)
• representations - Entity representations with key field values
• selection - Field selection from GraphQL query

Returns

Vector of resolved entities (or None for missing entities)

Errors

Returns error if database query fails

pub async fn resolve_entities_from_db_with_tracing( &self, typename: &str, representations: &[EntityRepresentation], selection: &FieldSelection, _trace_context: Option<FederationTraceContext>, ) -> Result<Vec<Option<Value>>>

Resolve entities from database with optional distributed tracing.

Arguments

• typename - The entity type name (e.g., “User”)
• representations - Entity representations with key field values
• selection - Field selection from GraphQL query
• trace_context - Optional W3C trace context for span creation

Returns

Vector of resolved entities (or None for missing entities)

Errors

Returns error if database query fails