Trait DeCollectionStream 

pub trait DeCollectionStream:
    Send
    + Sync
    + InputBuffer {
    // Required methods
    fn insert(
        &mut self,
        data: &[u8],
        metadata: &Option<Variant>,
    ) -> AnyResult<()>;
    fn delete(
        &mut self,
        data: &[u8],
        metadata: &Option<Variant>,
    ) -> AnyResult<()>;
    fn update(
        &mut self,
        data: &[u8],
        metadata: &Option<Variant>,
    ) -> AnyResult<()>;
    fn reserve(&mut self, reservation: usize);
    fn truncate(&mut self, len: usize);
    fn stage(
        &self,
        buffers: Vec<Box<dyn InputBuffer>>,
    ) -> Box<dyn StagedBuffers>;
    fn fork(&self) -> Box<dyn DeCollectionStream>;
}

An input handle that deserializes and buffers records.

A trait for a type that wraps a ZSetHandle or an MapHandle and collects serialized relational data for the associated input stream. The client passes a byte array with a serialized data record (e.g., in JSON or CSV format) to insert, delete, and update methods. The record gets deserialized into the strongly typed representation expected by the input stream.

Instances of this trait are created by calling DeCollectionHandle::configure_deserializer. The data format accepted by the handle is determined by the record_format argument passed to this method.

The input handle internally buffers the deserialized records. Use the InputBuffer supertrait to push them to the circuit or extract them for later use.

Required Methods

fn insert(&mut self, data: &[u8], metadata: &Option<Variant>) -> AnyResult<()>

Buffer a new insert update.

metadata contains optional metadata attached by the transport adapter or parser, such as Kafka headers, topic name, etc. This metadata is passed as an aux argument to DeserializeWithContext::deserialize_with_context_aux.

Returns an error if deserialization fails, i.e., the serialized representation is corrupted or does not match the value type of the underlying input stream.

fn delete(&mut self, data: &[u8], metadata: &Option<Variant>) -> AnyResult<()>

Buffer a new delete update.

The data argument contains a serialized record whose type depends on the underlying input stream: streams created by RootCircuit::add_input_zset and RootCircuit::add_input_set methods support deletion by value, hence the serialized record must match the value type of the stream. Streams created with RootCircuit::add_input_map support deletion by key, so the serialized record must match the key type of the stream.

The record gets deserialized and pushed to the underlying input stream handle as a delete update.

metadata contains optional metadata attached by the transport adapter or parser, such as Kafka headers, topic name, etc. This metadata is passed as an aux argument to DeserializeWithContext::deserialize_with_context_aux.

Returns an error if deserialization fails, i.e., the serialized representation is corrupted or does not match the value or key type of the underlying input stream.

fn update(&mut self, data: &[u8], metadata: &Option<Variant>) -> AnyResult<()>

Buffer a new update that will modify an existing record.

metadata contains optional metadata attached by the transport adapter or parser, such as Kafka headers, topic name, etc. This metadata is passed as an aux argument to DeserializeWithContext::deserialize_with_context_aux.

This method can only be called on streams created with RootCircuit::add_input_map and will fail on other streams. The serialized record must match the update type of this stream, specified as a type argument to Catalog::register_input_map.

fn reserve(&mut self, reservation: usize)

Reserve space for at least reservation more updates in the internal input buffer.

Reservations are not required but can be used when the number of inputs is known ahead of time to reduce reallocations.

fn truncate(&mut self, len: usize)

Removes any updates beyond the first len.

fn stage(&self, buffers: Vec<Box<dyn InputBuffer>>) -> Box<dyn StagedBuffers>

Stages all of the buffers, which must have been obtained from a Parser for this stream, into a StagedBuffers that may later be used to push the collected data into the circuit. See StagedBuffers for more information.

fn fork(&self) -> Box<dyn DeCollectionStream>

Create a new deserializer with the same configuration connected to the same input stream. The new deserializer has an independent buffer that is initially empty.

Dyn Compatibility

This trait is dyn compatible.

In older versions of Rust, dyn compatibility was called "object safety".

Implementors