Class: Participant

vortexdds~Participant(domainIdopt, qosopt)

A DDS domain participant, representing a connection by your program to a DDS Domain.

Typically, your application will create only one participant. All other DDS entities are created through a participant or one of its child entities via factory methods such as Participant.createPublisher().

At the end of your program, you can release all the entities owned directly or indirectly by the participant by calling Entity.delete().

Note that DDS resources and memory consumed by DDS entities cannot be automatically reclaimed by the NodeJS engine. Once your application is finished with an Entity, you must call delete() to release these DDS resources.

Constructor

new Participant(domainIdopt, qosopt)

Create a Participant instance.

Extends:
Parameters:
Name Type Attributes Default Description
domainId number <optional>

An integer between 0 and 230. Must match the value specified in the OSPL configuration file referenced by the OSPL_CONFIG environment variable.
qos module:vortexdds.QoS <optional>
 QoS.participantDefault()

A QoS object.

Uses the QoS.participantDefault() if qos is not provided.

Note that there is no functional difference between passing no argument and passing in null for qos while creating a participant.
Throws:

if a participant cannot be created.

Type
module:vortexdds.DDSError

Extends

Members

qos :module:vortexdds.QoS

The existing QoS policies for the entity.

Type:
Overrides:

Methods

createPublisher(qosopt) → {module:vortexdds.Publisher}

Creates a DDS Publisher owned by this participant.

Typically, you create a Publisher in order specify one or more 'partitions' to which publisher-owned writers will publish data. Partitions are specified via the partition policy of a QoS object.

Note that DDS resources and memory consumed by DDS entities cannot be automatically reclaimed by the NodeJS engine. Once your application is finished with an Entity, you must call delete() to release these DDS resources.

Parameters:
Name Type Attributes Default Description
qos module:vortexdds.QoS <optional>
 QoS.publisherDefault()

quality-of-service policies for the publisher.

Uses the QoS.publisherDefault() if qos is not provided.

Note that there is no functional difference between passing no argument and passing in null for qos while creating a publisher.
Throws:

if the publisher cannot be created

Type
module:vortexdds.DDSError
Returns:

the Publisher instance

Type
module:vortexdds.Publisher
Example
// specify a partition policy via a QoS object
const dds = require('vortexdds');
const dp = somePreviouslyCreatedParticipant;
const qos = dds.QoS.publisherDefault();
qos.partition = { names: ['part1', 'part2']};
// Assuming dp is a Participant instance
const pub = dp.createPublisher(qos);
// ... use 'pub' object

createReader(topic, qosopt, listeneropt) → {module:vortexdds.Reader}

Creates a Reader for a topic on the 'default subscriber' of the participant.

Similar to Subscriber.createReader() except that a Reader created based in QoS properties of the 'default subscriber' for the domain.

The reader belongs to the participant from which it is created, and is automatically deleted when the participant is deleted.

Note that DDS resources and memory consumed by DDS entities cannot be automatically reclaimed by the NodeJS engine. Once your application is finished with an Entity, you must call delete() to release these DDS resources.

Parameters:
Name Type Attributes Default Description
topic module:vortexdds.Topic

the topic from which data will be read
qos module:vortexdds.QoS <optional>
 QoS.readerDefault()

quality-of-service policies for the reader.

If no argument is provided, then QoS.readerDefault() is used, whereas passing in a null value results in the topic's qos to be used.
listener module:vortexdds~ReaderListener <optional>
 null

an object defining listener callbacks for the reader
Throws:

if the reader cannot be created

Type
module:vortexdds.DDSError
Returns:

the Reader instance

Type
module:vortexdds.Reader

createStatusCondition(maskopt) → {module:vortexdds.StatusCondition}

Creates a StatusCondition for use in wait set.

Omitting the mask value results in all entity-appropriate status conditions being enabled.

Note that DDS resources and memory consumed by conditions cannot be automatically reclaimed by the NodeJS engine. Conditions are automatically deleted when the parent entity is deleted. Otherwise, when your application is finished with a Condition, you may call Condition.delete() to release these DDS resources.

Parameters:
Name Type Attributes Default Description
mask module:vortexdds.StatusMask <optional>
 null

mask of StatusMask values of interest
Overrides:
Throws:

if the status mask is invalid

Type
module:vortexdds.DDSError
Returns:
Type
module:vortexdds.StatusCondition

createSubscriber(qosopt) → {module:vortexdds.Subscriber}

Creates a DDS Subscriber owned by this participant.

Typically, you create a Publisher in order specify one or more 'partitions' to which publisher-owned writers will publish data. Partitions are specified via the partition policy of a QoS object.

Note that DDS resources and memory consumed by DDS entities cannot be automatically reclaimed by the NodeJS engine. Once your application is finished with an Entity, you must call delete() to release these DDS resources.

Parameters:
Name Type Attributes Default Description
qos module:vortexdds.QoS <optional>
 QoS.subscriberDefault()

quality-of-service policies for the subscriber.

Uses the QoS.subscriberDefault() if qos is not provided.

Note that there is no functional difference between passing no argument and passing in null for qos while creating a subscriber.
Throws:

if the subscriber cannot be created

Type
module:vortexdds.DDSError
Returns:

the Subscriber instance

Type
module:vortexdds.Subscriber
Example
// specify a partition policy via a QoS object
const dds = require('vortexdds');
const dp = somePreviouslyCreatedParticipant;
const qos = dds.QoS.subscriberDefault();
qos.partition = { names: ['part1', 'part2']};
// Assuming dp is a Participant instance
const sub = dp.createSubscriber(qos);
// ... use 'sub' object

createTopic(topicName, typeSupport, qosopt, listeneropt) → {module:vortexdds.Topic}

Creates a DDS Topic of the given name and type.

Type information is encoded in a TypeSupport object, typically returned by importIDL().

Topic creatation can fail if the DDS domain already has an identically named topic, but with different QoS or type information.

The topic belongs to the participant from which it is created, and is automatically deleted when the participant is deleted.

Note that DDS resources and memory consumed by DDS entities cannot be automatically reclaimed by the NodeJS engine. Once your application is finished with an Entity, you must call delete() to release these DDS resources.

Parameters:
Name Type Attributes Default Description
topicName string

a valid DDS topic name
typeSupport module:vortexdds.TypeSupport

a object defining the data type associated with the topic
qos module:vortexdds.QoS <optional>
 QoS.topicDefault()

a specification of the quality-of-service properties for the topic.

Uses the QoS.topicDefault() if qos is not provided.

Note that there is no functional difference between passing no argument and passing in null for qos while creating a topic.
listener module:vortexdds~TopicListener <optional>
 null

an object defining listener callbacks for the topic
Throws:

if the topic already exists, but with different type or QoS parameters

Type
module:vortexdds.DDSError
Returns:

a topic instnace

Type
module:vortexdds.Topic

createWriter(topic, qosopt, listeneropt) → {module:vortexdds.Writer}

Creates a Reader for a topic on the 'default publisher' of the participant.

Similar to Publisher.createWriter() except that a Writer created based in QoS properties of the 'default publisher' for the domain.

The writer belongs to the participant from which it is created, and is automatically deleted when the participant is deleted.

Note that DDS resources and memory consumed by DDS entities cannot be automatically reclaimed by the NodeJS engine. Once your application is finished with an Entity, you must call delete() to release these DDS resources.

Parameters:
Name Type Attributes Default Description
topic module:vortexdds.Topic

the topic to which data will be written
qos module:vortexdds.QoS <optional>
 QoS.writerDefault()

quality-of-service policies for the writer.

If no argument is provided, then QoS.writerDefault() is used, whereas passing in a null value results in the topic's qos to be used.
listener module:vortexdds~WriterListener <optional>
 null

an object defining listener callbacks for the writer
Throws:

if the writer cannot be created

Type
module:vortexdds.DDSError
Returns:

the Writer instance

Type
module:vortexdds.Writer

delete() → {external:Promise}

Releases the DDS resources associated with the entity and all its 'child' entities.

In some cases, releasing DDS resources can take several seconds. This methods returns a Promise that enables you to do processing after all the resources have been released.

Overrides:
Returns:
Type
external:Promise

findTopic(topicName) → {external:Promise.<module:vortexdds.Topic>}

Asyncrhonously search for an existing DDS topic.

Return a Promise, whose resolved value is the found topic. The Promise is rejected if the topic cannot be found or another error occurs.

Parameters:
Name Type Description
topicName string

the name of topic to find
Returns:

a promise that resolves to the desired topic

Type
external:Promise.<module:vortexdds.Topic>
Example
const dds = require('vortexdds');
const dp = someAlreadyCreatedParticipant;
dp.findTopic('MyTopic')
.then(topic => {
    // do something with the found topic
})
.catch(err => {
    // process any exception
})
.then(_ => {
    // cleanup: do any processing necessary after both
    // success and failure
});

getBuiltinSubscriber() → {module:vortexdds.Subscriber}

Creates the builtin subscriber on this participant.

Returns:
Type
module:vortexdds.Subscriber

statusChanges() → {module:vortexdds.StatusMask}

Return the DDS communication statuses that have changed since this method was last called.

Overrides:
Returns:

a mask of statuses that have changed

Type
module:vortexdds.StatusMask