Struct rustdds::dds::with_key::DataReader

pub struct DataReader<D: Keyed, DA: DeserializerAdapter<D> = CDRDeserializerAdapter<D>> { /* private fields */ }

DDS DataReader for with_key topics.

Examples

use serde::{Serialize, Deserialize};
use rustdds::*;
use rustdds::with_key::DataReader;
use rustdds::serialization::CDRDeserializerAdapter;

let domain_participant = DomainParticipant::new(0).unwrap();
let qos = QosPolicyBuilder::new().build();
let subscriber = domain_participant.create_subscriber(&qos).unwrap();

#[derive(Serialize, Deserialize)]
struct SomeType { a: i32 }
impl Keyed for SomeType {
  type K = i32;

  fn key(&self) -> Self::K {
    self.a
  }
}

// WithKey is important
let topic = domain_participant.create_topic("some_topic".to_string(), "SomeType".to_string(), &qos, TopicKind::WithKey).unwrap();
let data_reader = subscriber.create_datareader::<SomeType, CDRDeserializerAdapter<_>>(&topic, None);

Note: Many DataReader methods require mutable access to self, because they need to mutate the datasample cache, which is an essential content of this struct.

Implementations

impl<D, DA> DataReader<D, DA>

where D: Keyed + 'static, DA: DeserializerAdapter<D> + DefaultDecoder<D>,

pub fn read( &mut self, max_samples: usize, read_condition: ReadCondition ) -> ReadResult<Vec<DataSample<&D>>>

Reads amount of samples found with max_samples and read_condition parameters.

Arguments

• max_samples - Limits maximum amount of samples read
• read_condition - Limits results by condition

Examples

let domain_participant = DomainParticipant::new(0).unwrap();
let qos = QosPolicyBuilder::new().build();
let subscriber = domain_participant.create_subscriber(&qos).unwrap();

// WithKey is important
let topic = domain_participant.create_topic("some_topic".to_string(), "SomeType".to_string(), &qos, TopicKind::WithKey).unwrap();
let mut data_reader = subscriber.create_datareader::<SomeType, CDRDeserializerAdapter<_>>(&topic, None).unwrap();

// Wait for data to arrive...

if let Ok(datas) = data_reader.read(10, ReadCondition::not_read()) {
  for data in datas.iter() {
    // do something
  }
}

pub fn take( &mut self, max_samples: usize, read_condition: ReadCondition ) -> ReadResult<Vec<DataSample<D>>>

Takes amount of sample found with max_samples and read_condition parameters.

Arguments

• max_samples - Limits maximum amount of samples read
• read_condition - Limits results by condition

Examples

let domain_participant = DomainParticipant::new(0).unwrap();
let qos = QosPolicyBuilder::new().build();
let subscriber = domain_participant.create_subscriber(&qos).unwrap();

// WithKey is important
let topic = domain_participant.create_topic("some_topic".to_string(), "SomeType".to_string(), &qos, TopicKind::WithKey).unwrap();
let mut data_reader = subscriber.create_datareader::<SomeType, CDRDeserializerAdapter<_>>(&topic, None).unwrap();

// Wait for data to arrive...

if let Ok(datas) = data_reader.take(10, ReadCondition::not_read()) {
  for data in datas.iter() {
    // do something
  }
}

pub fn read_next_sample(&mut self) -> ReadResult<Option<DataSample<&D>>>

Reads next unread sample

Examples

let domain_participant = DomainParticipant::new(0).unwrap();
let qos = QosPolicyBuilder::new().build();
let subscriber = domain_participant.create_subscriber(&qos).unwrap();

// WithKey is important
let topic = domain_participant.create_topic("some_topic".to_string(), "SomeType".to_string(), &qos, TopicKind::WithKey).unwrap();
let mut data_reader = subscriber.create_datareader::<SomeType, CDRDeserializerAdapter<_>>(&topic, None).unwrap();

// Wait for data to arrive...

while let Ok(Some(data)) = data_reader.read_next_sample() {
  // do something
}

pub fn take_next_sample(&mut self) -> ReadResult<Option<DataSample<D>>>

Takes next unread sample

Examples

let domain_participant = DomainParticipant::new(0).unwrap();
let qos = QosPolicyBuilder::new().build();
let subscriber = domain_participant.create_subscriber(&qos).unwrap();

// WithKey is important
let topic = domain_participant.create_topic("some_topic".to_string(), "SomeType".to_string(), &qos, TopicKind::WithKey).unwrap();
let mut data_reader = subscriber.create_datareader::<SomeType, CDRDeserializerAdapter<_>>(&topic, None).unwrap();

// Wait for data to arrive...

while let Ok(Some(data)) = data_reader.take_next_sample() {
  // do something
}

pub fn iterator(&mut self) -> ReadResult<impl Iterator<Item = Sample<&D, D::K>>>

Produces an iterator over the currently available NOT_READ samples. Yields only payload data, not SampleInfo metadata This is not called iter() because it takes a mutable reference to self.

Examples

let domain_participant = DomainParticipant::new(0).unwrap();
let qos = QosPolicyBuilder::new().build();
let subscriber = domain_participant.create_subscriber(&qos).unwrap();

// WithKey is important
let topic = domain_participant.create_topic("some_topic".to_string(), "SomeType".to_string(), &qos, TopicKind::WithKey).unwrap();
let mut data_reader = subscriber.create_datareader::<SomeType, CDRDeserializerAdapter<_>>(&topic, None).unwrap();

// Wait for data to arrive...

for data in data_reader.iterator() {
  // do something
}

pub fn conditional_iterator( &mut self, read_condition: ReadCondition ) -> ReadResult<impl Iterator<Item = Sample<&D, D::K>>>

Produces an iterator over the samples filtered by a given condition. Yields only payload data, not SampleInfo metadata

Examples

let domain_participant = DomainParticipant::new(0).unwrap();
let qos = QosPolicyBuilder::new().build();
let subscriber = domain_participant.create_subscriber(&qos).unwrap();

// WithKey is important
let topic = domain_participant.create_topic("some_topic".to_string(), "SomeType".to_string(), &qos, TopicKind::WithKey).unwrap();
let mut data_reader = subscriber.create_datareader::<SomeType, CDRDeserializerAdapter<_>>(&topic, None).unwrap();

// Wait for data to arrive...

for data in data_reader.conditional_iterator(ReadCondition::any()) {
  // do something
}

pub fn into_iterator( &mut self ) -> ReadResult<impl Iterator<Item = Sample<D, D::K>>>

Produces an iterator over the currently available NOT_READ samples. Yields only payload data, not SampleInfo metadata Removes samples from DataReader. Note! If the iterator is only partially consumed, all the samples it could have provided are still removed from the Datareader.

Examples

let domain_participant = DomainParticipant::new(0).unwrap();
let qos = QosPolicyBuilder::new().build();
let subscriber = domain_participant.create_subscriber(&qos).unwrap();

// WithKey is important
let topic = domain_participant.create_topic("some_topic".to_string(), "SomeType".to_string(), &qos, TopicKind::WithKey).unwrap();
let mut data_reader = subscriber.create_datareader::<SomeType, CDRDeserializerAdapter<_>>(&topic, None).unwrap();

// Wait for data to arrive...

for data in data_reader.into_iterator() {
  // do something
}

pub fn into_conditional_iterator( &mut self, read_condition: ReadCondition ) -> ReadResult<impl Iterator<Item = Sample<D, D::K>>>

Produces an iterator over the samples filtered by the given condition. Yields only payload data, not SampleInfo metadata Note! If the iterator is only partially consumed, all the samples it could have provided are still removed from the Datareader.

Examples

let domain_participant = DomainParticipant::new(0).unwrap();
let qos = QosPolicyBuilder::new().build();
let subscriber = domain_participant.create_subscriber(&qos).unwrap();

// WithKey is important
let topic = domain_participant.create_topic("some_topic".to_string(), "SomeType".to_string(), &qos, TopicKind::WithKey).unwrap();
let mut data_reader = subscriber.create_datareader::<SomeType, CDRDeserializerAdapter<_>>(&topic, None).unwrap();

// Wait for data to arrive...

for data in data_reader.into_conditional_iterator(ReadCondition::not_read()) {
  // do something
}

pub fn read_instance( &mut self, max_samples: usize, read_condition: ReadCondition, instance_key: Option<<D as Keyed>::K>, this_or_next: SelectByKey ) -> ReadResult<Vec<DataSample<&D>>>

Works similarly to read(), but will return only samples from a specific instance. The instance is specified by an optional key. In case the key is not specified, the smallest (in key order) instance is selected. If a key is specified, then the parameter this_or_next specifies whether to access the instance with specified key or the following one, in key order.

This should cover DDS DataReader methods read_instance, read_next_instance, read_next_instance_w_condition.

Examples

let domain_participant = DomainParticipant::new(0).unwrap();
let qos = QosPolicyBuilder::new().build();
let subscriber = domain_participant.create_subscriber(&qos).unwrap();

// WithKey is important
let topic = domain_participant.create_topic("some_topic".to_string(), "SomeType".to_string(), &qos, TopicKind::WithKey).unwrap();
let mut data_reader = subscriber.create_datareader::<SomeType, CDRDeserializerAdapter<_>>(&topic, None).unwrap();

// Wait for data to arrive...

if let Ok(datas) = data_reader.read_instance(10, ReadCondition::any(), Some(3), SelectByKey::This) {
  for data in datas.iter() {
    // do something
  }
}

pub fn take_instance( &mut self, max_samples: usize, read_condition: ReadCondition, instance_key: Option<<D as Keyed>::K>, this_or_next: SelectByKey ) -> ReadResult<Vec<DataSample<D>>>

Similar to read_instance, but will return owned datasamples This should cover DDS DataReader methods take_instance, take_next_instance, take_next_instance_w_condition.

Examples

let domain_participant = DomainParticipant::new(0).unwrap();
let qos = QosPolicyBuilder::new().build();
let subscriber = domain_participant.create_subscriber(&qos).unwrap();

// WithKey is important
let topic = domain_participant.create_topic("some_topic".to_string(), "SomeType".to_string(), &qos, TopicKind::WithKey).unwrap();
let mut data_reader = subscriber.create_datareader::<SomeType, CDRDeserializerAdapter<_>>(&topic, None).unwrap();

// Wait for data to arrive...

if let Ok(datas) = data_reader.take_instance(10, ReadCondition::any(), Some(3), SelectByKey::Next) {
  for data in datas.iter() {
    // do something
  }
}

pub fn wait_for_historical_data(&mut self, _max_wait: Duration) -> bool

Return values: true - got all historical data false - timeout before all historical data was received

pub fn get_matched_publications( &self ) -> impl Iterator<Item = PublicationBuiltinTopicData>

pub fn async_sample_stream(self) -> DataReaderStream<D, DA>

An async stream for reading the (bare) data samples. The resulting Stream can be used to get another stream of status events.

Trait Implementations

impl<D, DA> Evented for DataReader<D, DA>

where D: Keyed, DA: DeserializerAdapter<D>,

fn register( &self, poll: &Poll, token: Token, interest: Ready, opts: PollOpt ) -> Result<()>

Register self with the given Poll instance.

fn reregister( &self, poll: &Poll, token: Token, interest: Ready, opts: PollOpt ) -> Result<()>

Re-register self with the given Poll instance.

fn deregister(&self, poll: &Poll) -> Result<()>

Deregister self from the given Poll instance

impl<D, DA> HasQoSPolicy for DataReader<D, DA>

where D: Keyed + 'static, DA: DeserializerAdapter<D>,

fn qos(&self) -> QosPolicies

impl<D, DA> RTPSEntity for DataReader<D, DA>

where D: Keyed + 'static, DA: DeserializerAdapter<D>,

fn guid(&self) -> GUID

fn entity_id(&self) -> EntityId

fn guid_prefix(&self) -> GuidPrefix

impl<D, DA> Source for DataReader<D, DA>

where D: Keyed, DA: DeserializerAdapter<D>,

fn register( &mut self, registry: &Registry, token: Token, interests: Interest ) -> Result<()>

Register self with the given Registry instance.

fn reregister( &mut self, registry: &Registry, token: Token, interests: Interest ) -> Result<()>

Re-register self with the given Registry instance.

fn deregister(&mut self, registry: &Registry) -> Result<()>

Deregister self from the given Registry instance.

impl<'a, D, DA> StatusEvented<'a, DataReaderStatus, SimpleDataReaderEventStream<'a, D, DA>> for DataReader<D, DA>

where D: Keyed + 'static, DA: DeserializerAdapter<D>,

fn as_status_evented(&mut self) -> &dyn Evented

fn as_status_source(&mut self) -> &mut dyn Source

fn as_async_status_stream(&'a self) -> SimpleDataReaderEventStream<'a, D, DA>

fn try_recv_status(&self) -> Option<DataReaderStatus>