Module schema 

Schema inference, resolution, and evolution framework. Schema inference, resolution, and evolution framework.

This module implements the foundation of LaminarDB’s extensible connector schema system (F-SCHEMA-001/002/003):

• Capability traits (traits) — six opt-in traits that connectors implement to declare schema capabilities
• Schema resolver (resolver) — five-level priority chain for determining a source’s Arrow schema
• Format inference (inference) — registry of format-specific schema inferencers with built-in JSON, CSV, and raw support
• Bridge adapters (bridge) — adapters between legacy RecordDeserializer / RecordSerializer and the new FormatDecoder / FormatEncoder traits
• JSON format (json) — JSON decoder, encoder, and JSONB binary format (F-SCHEMA-004)
• CSV format ([csv]) — CSV decoder with DuckDB-style type coercion (F-SCHEMA-005)
• Schema evolution (evolution) — diff, evaluate, and apply schema changes with configurable compatibility modes (F-SCHEMA-009)

Architecture

SourceConnector
  ├── as_schema_provider()      → SchemaProvider
  ├── as_schema_inferable()     → SchemaInferable
  ├── as_schema_registry_aware()→ SchemaRegistryAware
  └── as_schema_evolvable()     → SchemaEvolvable

SchemaResolver::resolve()
  1. Full DDL         → Declared
  2. Registry         → Registry { schema_id }
  3. Provider         → SourceProvided
  4. Inference        → Inferred { sample_count }
  5. Error

Re-exports

pub use csv::CsvDecoder;

pub use csv::CsvDecoderConfig;

pub use csv::FieldCountMismatchStrategy;

pub use error::SchemaError;

pub use error::SchemaResult;

pub use evolution::diff_schemas_by_name;

pub use evolution::is_safe_widening;

pub use evolution::DefaultSchemaEvolver;

pub use evolution::EvolutionResult;

pub use evolution::EvolutionTrigger;

pub use evolution::SchemaEvolutionEngine;

pub use evolution::SchemaHistory;

pub use evolution::SchemaHistoryEntry;

pub use inference::CsvFormatInference;

pub use inference::FormatInference;

pub use inference::FormatInferenceRegistry;

pub use inference::JsonFormatInference;

pub use inference::RawFormatInference;

pub use inference::FORMAT_INFERENCE_REGISTRY;

pub use json::JsonDecoder;

pub use json::JsonDecoderConfig;

pub use json::JsonEncoder;

pub use json::JsonbAccessor;

pub use json::JsonbEncoder;

pub use json::TypeMismatchStrategy;

pub use json::UnknownFieldStrategy;

pub use parquet::ParquetDecoder;

pub use parquet::ParquetDecoderConfig;

pub use parquet::ParquetEncoder;

pub use parquet::ParquetEncoderConfig;

pub use parquet::ParquetSchemaProvider;

pub use parquet::RowGroupPredicate;

pub use resolver::DeclaredColumn;

pub use resolver::DeclaredSchema;

pub use resolver::FieldOrigin;

pub use resolver::ResolutionKind;

pub use resolver::ResolvedSchema;

pub use resolver::SchemaResolver;

pub use traits::ArrayInference;

pub use traits::ColumnProjection;

pub use traits::CompatibilityMode;

pub use traits::ConfigOption;

pub use traits::ConfigValueType;

pub use traits::ConnectorConfigSchema;

pub use traits::EvolutionVerdict;

pub use traits::FieldInferenceDetail;

pub use traits::FormatDecoder;

pub use traits::FormatEncoder;

pub use traits::InferenceConfig;

pub use traits::InferenceWarning;

pub use traits::InferredSchema;

pub use traits::NumberInference;

pub use traits::RegisteredSchema;

pub use traits::RegistryConfig;

pub use traits::RegistryCredentials;

pub use traits::RegistrySchemaType;

pub use traits::SchemaChange;

pub use traits::SchemaEvolvable;

pub use traits::SchemaInferable;

pub use traits::SchemaProvider;

pub use traits::SchemaRegistryAware;

pub use traits::WarningSeverity;

pub use types::FieldMeta;

pub use types::RawRecord;

pub use types::SinkConfig;

pub use types::SourceConfig;

pub use types::SourceMetadata;

Modules

bridge

Bridge adapters between legacy serde traits and the new schema traits.

csv

CSV format decoder implementing FormatDecoder.

error

Schema error types.

evolution

Schema evolution engine (F-SCHEMA-009).

inference

Format inference registry and built-in format inferencers.

json

JSON format decoder, encoder, and JSONB binary format.

parquet

Parquet format decoder, encoder, and schema provider (F-SCHEMA-007).

resolver

Schema resolver and merge engine.

traits

Capability traits for the extensible connector framework.

types

Schema types used across the connector framework.