Struct Handler 

pub struct Handler { /* private fields */ }

Converts between serialized protobuf messages and Arrow record batches for a single message type, exchanging Arrow data through the C Data Interface.

Descriptors are passed as serialized bytes and Arrow data as ArrowArray/ArrowSchema pairs, so this type works with any arrow version on the caller’s side.

Implementations

impl Handler

pub fn try_new( file_descriptor_set: &[u8], message_name: &str, config: PtarsConfig, ) -> Result<Self, PtarsError>

Create a handler from a serialized google.protobuf.FileDescriptorSet (e.g. the output of protoc --descriptor_set_out) and a fully qualified message name.

pub fn try_new_from_file_descriptor_protos( file_descriptor_protos: &[&[u8]], message_name: &str, config: PtarsConfig, ) -> Result<Self, PtarsError>

Create a handler from serialized google.protobuf.FileDescriptorProto messages and a fully qualified message name.

Files must be ordered so that imports appear before the files that depend on them.

pub fn arrow_schema(&self) -> Result<ArrowSchema, PtarsError>

The Arrow schema of the record batches produced by Handler::decode, exported as a C Data Interface struct-typed schema.

pub fn decode( &self, array: ArrowArray, schema: &ArrowSchema, ) -> Result<(ArrowArray, ArrowSchema), PtarsError>

Decode an Arrow binary array of serialized protobuf messages into a record batch, returned as a struct-typed array over the C Data Interface.

The input must be a Binary, LargeBinary or BinaryView array where each value is one serialized message; nulls decode to null rows.

pub fn decode_bytes( &self, messages: &[Option<&[u8]>], ) -> Result<(ArrowArray, ArrowSchema), PtarsError>

Decode serialized protobuf messages into a record batch, returned as a struct-typed array over the C Data Interface.

Convenience over Handler::decode for callers that do not already hold the messages in an Arrow array; None decodes to a null row.

pub fn encode( &self, array: ArrowArray, schema: &ArrowSchema, ) -> Result<(ArrowArray, ArrowSchema), PtarsError>

Encode a record batch (passed as a struct-typed array over the C Data Interface) into a Binary array of serialized protobuf messages, returned over the C Data Interface.