Module: dds.core¶
-
dds.core.
LENGTH_UNLIMITED
= -1¶ int(x=0) -> int or long int(x, base=10) -> int or long
Convert a number or string to an integer, or return 0 if no arguments are given. If x is floating point, the conversion truncates towards zero. If x is outside the integer range, the function returns a long instead.
If x is not a number or if base is given, then x must be a string or Unicode object representing an integer literal in the given base. The literal can be preceded by ‘+’ or ‘-‘ and be surrounded by whitespace. The base defaults to 10. Valid bases are 0 and 2-36. Base 0 means to interpret the base from the string as an integer literal. >>> int(‘0b100’, base=0) 4
-
class
dds.core.
Duration
¶ Bases:
dds.core.Time
Parameters: - sec – an integer seconds value (default: 0)
- nanosec – an integer nanoseconds value (default: 0)
-
infinite
¶ Return an infinite Duration
-
exception
dds.core.
Error
¶ Bases:
exceptions.Exception
Base class for DDS Exceptions
-
class
dds.core.
GUID
¶ Bases:
object
The GUID object holds a single member ‘value’ of type bytearray(16)
-
class
dds.core.
InconsistentTopicStatus
¶ Represents the Inconsistent Topic status of an entity. This is provided in the associated callback, or can be obtained by calling get_inconsistent_topic_status() on Topic, or DomainParticipant.
The following values are included in the status:
-
total_count
¶ int – Cummulative count of the discovered Topics having a matching name and inconsistent characteristics.
-
total_count_change
¶ int – Change in total_count since the last time the listener was called or status was read.
-
-
class
dds.core.
InstanceHandle
¶ Identifies an instance within the scope of a particular DataReader. The following values are defined:
- HANDLE_NIL
- NIL (an alias for HANDLE_NIL)
-
class
dds.core.
InstanceState
¶ InstanceState indicates the state of a data instance.
The following values are defined:
- ALIVE_INSTANCE_STATE
- NOT_ALIVE_DISPOSED_INSTANCE_STATE
- NOT_ALIVE_NO_WRITERS_INSTANCE_STATE
- NOT_ALIVE_INSTANCE_STATE
- ANY_INSTANCE_STATE
-
class
dds.core.
LivelinessChangedStatus
¶ Status related to the on_liveliness_changed listener methods of the DataReader, Subscriber, and DomainParticipant structures.
The following values are included in the status:
-
alive_count
¶ int – The number of ‘active’ DataWriters matched to this DataReader.
-
not_alive_count
¶ int – The number of ‘not-alive’ DataWriters matched to this DataReader.
-
alive_count_change
¶ int – Change in alive_count since the last time the listener was called or status was read.
-
not_alive_count_change
¶ int – Change in not_alive_count since the last time the listener was called or status was read.
-
last_publication_handle
¶ dds.core.InstanceHandle
– Handle identifying the most recent DataWriter whose liveliness changed.
-
-
class
dds.core.
LivelinessLostStatus
¶ Status related to the on_liveliness_lost listener methods of the DataWriter, Publisher, and DomainParticipant structures.
The following values are included in the status:
-
total_count
¶ int – Cummulative number of times that an ‘alive’ DataWriter became not alive.
-
total_count_change
¶ int – Change in total_count since the last time the listener was called or status was read.
-
-
class
dds.core.
OfferedDeadlineMissedStatus
¶ Status related to the on_offered_deadline_missed listener methods of the DataWriter, Publisher, and DomainParticipant structures.
The following values are included in the status:
-
total_count
¶ int – Cummulative count of the number of deadlines missed by this DataWriter.
-
total_count_change
¶ int – Change in total_count since the last time the listener was called or status was read.
-
last_instance_handle
¶ dds.core.InstanceHandle
– Handle identifying the most recent instance whose deadline was missed.
-
-
class
dds.core.
OfferedIncompatibleQosStatus
¶ Status related to the on_offered_incompatible_qos listener methods of the DataWriter, Publisher, and DomainParticipant structures.
The following values are included in the status:
-
total_count
¶ int – Cummulative count of the number of DataWriters discovered having matching Topic and incompatible QoS.
-
total_count_change
¶ int – Change in total_count since the last time the listener was called or status was read.
-
last_policy_id
¶ dds.core.QosPolicyId
– Id of the most recent requested incompatible QoS policy.
-
-
class
dds.core.
PublicationMatchedStatus
¶ Status related to the on_publication_matched listener methods of the DataWriter, Publisher, and DomainParticipant structures.
The following values are included in the status:
-
total_count
¶ int – Cummulative count of the number of times this DataWriter has discovered a matching DataReader.
-
total_count_change
¶ int – Change in total_count since the last time the listener was called or status was read.
-
current_count
¶ int – The current number of DataReaders matched to the DataWriter.
-
current_count_change
¶ int – Change in current_count since the last time the listener was called or status was read.
-
last_subscription_handle
¶ dds.core.QosPolicyId
– The handle of the most recent matched DataReader
-
-
class
dds.core.
QosPolicyCount
¶ Holds a QosPolicyId value and a counter to indicate the number of events associated with that PolicyId.
-
class
dds.core.
QosPolicyId
¶ Each standard QoS Policy has an associated ID that is used in the OfferedIncompatibleQosStatus and RequestedIncompatibleQosStatus objects.
The following values are defined:
- USERDATA_QOS_POLICY_ID
- DURABILITY_QOS_POLICY_ID
- PRESENTATION_QOS_POLICY_ID
- DEADLINE_QOS_POLICY_ID
- LATENCYBUDGET_QOS_POLICY_ID
- OWNERSHIP_QOS_POLICY_ID
- OWNERSHIPSTRENGTH_QOS_POLICY_ID
- LIVELINESS_QOS_POLICY_ID
- TIMEBASEDFILTER_QOS_POLICY_ID
- PARTITION_QOS_POLICY_ID
- RELIABILITY_QOS_POLICY_ID
- DESTINATIONORDER_QOS_POLICY_ID
- HISTORY_QOS_POLICY_ID
- RESOURCELIMITS_QOS_POLICY_ID
- ENTITYFACTORY_QOS_POLICY_ID
- WRITERDATALIFECYCLE_QOS_POLICY_ID
- READERDATALIFECYCLE_QOS_POLICY_ID
- TOPICDATA_QOS_POLICY_ID
- GROUPDATA_QOS_POLICY_ID
- TRANSPORTPRIORITY_QOS_POLICY_ID
- LIFESPAN_QOS_POLICY_ID
- DURABILITYSERVICE_QOS_POLICY_ID
- DATA_REPRESENTATION_QOS_POLICY_ID
- TYPE_CONSISTENCY_ENFORCEMENT_QOS_POLICY_ID
-
class
dds.core.
RequestedDeadlineMissedStatus
¶ Status related to the on_requested_deadline_missed listener methods of the DataReader, Subscriber, and DomainParticipant structures.
The following values are included in the status:
- total_count: Cummulative count of the number of detected deadline misses for any instance read by the DataReader.
- total_count_change: Change in total_count since the last time the listener was called or status was read.
- last_instance_handle: Handle identifying the most recent instance whose deadline was missed.
-
class
dds.core.
RequestedIncompatibleQosStatus
¶ Status related to the on_requested_incompatible_qos listener methods of the DataReader, Subscriber, and DomainParticipant structures.
The following values are included in the status:
-
total_count
¶ int – Cummulative count of the number of discovered DataReaders having matching Topic and incompatible QoS.
-
total_count_change
¶ int – Change in total_count since the last time the listener was called or status was read.
-
last_policy_id
¶
-
-
class
dds.core.
ReturnCode
¶ ReturnCode is used to indicate the success or failure of various methods throughout the dds api.
The following values are defined:
- RETCODE_OK
- RETCODE_ERROR
- RETCODE_UNSUPPORTED
- RETCODE_BAD_PARAMETER
- RETCODE_PRECONDITION_NOT_MET
- RETCODE_OUT_OF_RESOURCES
- RETCODE_NOT_ENABLED
- RETCODE_IMMUTABLE_POLICY
- RETCODE_INCONSISTENT_POLICY
- RETCODE_ALREADY_DELETED
- RETCODE_TIMEOUT
- RETCODE_NO_DATA
-
class
dds.core.
Sample
¶ Bases:
object
A Sample object holds the user sample data and the associated
SampleInfo
-
data
¶ Access the sample data
-
info
¶ Access the SampleInfo
-
-
class
dds.core.
SampleInfo
¶ Bases:
object
The SampleInfo structure contains meta-data information associated with each sample.
-
absolute_generation_rank
¶ he generation difference between this sample and the most recent sample. The absolute_generation_rank indicates the generation difference (ie, the number of times the instance was disposed and became alive again) between this sample, and the most recent sample (possibly not in the returned collection) of this instance.
-
disposed_generation_count
¶ The number of times the instance has become ‘ALIVE’ after being explicitly disposed. (Computed at the time the sample arrives at the DataReader.)
-
generation_rank
¶ The generation difference of this sample and the most recent sample in the collection. generation_rank indicates the generation difference (ie, the number of times the instance was disposed and became alive again) between this sample, and the most recent sample in the collection related to this instance.
-
instance_handle
¶ The handle that locally identifies the associated instance.
-
instance_state
¶ Indicates whether the associated instance currently exists. instance_state can be one of:
- InstanceState.ALIVE_INSTANCE_STATE
- InstanceState.NOT_ALIVE_DISPOSED_INSTANCE_STATE
- InstanceState.NOT_ALIVE_NO_WRITERS_INSTANCE_STATE
Can use DDS_NOT_ALIVE_INSTANCE_STATE as a test (bitwise AND) for either ‘NOT_ALIVE’ state.
-
no_writers_generation_count
¶ The number of times the instance has become ‘ALIVE’ after being automatically disposed due to no active writers.
-
publication_handle
¶ The local handle of the source DataWriter.
-
reception_timestamp
¶ The time provided by the DataWriter when the sample was written.
-
sample_rank
¶ Number of samples related to this instances that follow in the collection returned by the DataReader read or take operations.
-
sample_state
¶ The associated data sample has/has not been read previously. sample_state indicates whether or not the DataReader has previously read the associated sample.
One of:
SampleState
.READ_SAMPLE_STATESampleState
.NOT_READ_SAMPLE_STATE
Use ANY_SAMPLE_STATE to test for either state.
-
source_timestamp
¶ The time provided by the DataWriter when the sample was written.
-
valid_data
¶ Set to true (non-zero) if the associated DataSample contains data. The associated DataSample may not contain data if it this sample indicates a change in sample state (for example ALIVE -> DISPOSED).
-
view_state
¶ Associated instance has/has not been seen before. view_state indicates whether the DataReader has already seen samples for the most current generation of the related instance.
view_state can be one of:
- ViewState.NEW_VIEW_STATE
- ViewState.NOT_NEW_VIEW_STATE
-
-
class
dds.core.
SampleLostStatus
¶ Status related to the on_sample_lost listener methods of the DataReader, Subscriber, and DomainParticipant structures.
The following values are included in the status:
-
total_count
¶ int – Cummulative count of all samples lost under the Topic.
-
total_count_change
¶ int – Change in total_count since the last time the listener was called or status was read.
-
-
class
dds.core.
SampleRejectedStatus
¶ Status related to the on_sample_rejected listener methods of the DataReader, Subscriber, and DomainParticipant structures.
The following values are included in the status:
-
total_count
¶ int – Cummulative count of samples rejected by the DataReader.
-
total_count_change
¶ int – Change in total_count since the last time the listener was called or status was read.
-
last_reason
¶ dds.core.ReturnCode
– The reason for rejecting the most recently rejected sample.
-
last_instance_handle
¶ dds.core.InstanceHandle
– The handle of the instance associated with the most recently rejected sample.
-
-
class
dds.core.
SampleRejectedStatusKind
¶ SampleRejectedStatusKind indicates the reason for sample rejection The following values are defined:
- NOT_REJECTED
- REJECTED_BY_INSTANCE_LIMIT
- REJECTED_BY_SAMPLES_LIMIT
- REJECTED_BY_SAMPLES_PER_INSTANCE_LIMIT
-
class
dds.core.
SampleState
¶ SampleState indicates the ‘read’ state of a data sample.
The following values are defined:
- READ_SAMPLE_STATE
- NOT_READ_SAMPLE_STATE
- ANY_SAMPLE_STATE
-
class
dds.core.
StatusMask
¶ StatusMask values represent bit flags that can be ‘bitwise’ combined. These values are used to indicate changes in status. These are useful when examining the status changes of a DDS entity (for example DomainParticipant.get_status_changes()), or installing a listener on a DDS entity (for example DomainParticipant.set_listener()).
The following values are defined:
- NO_STATUS
- STATUS_MASK_NONE (an alias for NO_STATUS)
- INCONSISTENT_TOPIC_STATUS
- OFFERED_DEADLINE_MISSED_STATUS
- REQUESTED_DEADLINE_MISSED_STATUS
- OFFERED_INCOMPATIBLE_QOS_STATUS
- REQUESTED_INCOMPATIBLE_QOS_STATUS
- SAMPLE_LOST_STATUS
- SAMPLE_REJECTED_STATUS
- DATA_ON_READERS_STATUS
- DATA_AVAILABLE_STATUS
- LIVELINESS_LOST_STATUS
- LIVELINESS_CHANGED_STATUS
- PUBLICATION_MATCHED_STATUS
- SUBSCRIPTION_MATCHED_STATUS
- ALL_STATUS
-
class
dds.core.
SubscriptionMatchedStatus
¶ Status related to the on_subscription_matched listener methods of the DataReader, Subscriber, and DomainParticipant structures.
The following values are included in the status:
-
total_count
¶ int – Cummulative count of the number of times this DataReader has discovered a matching DataWriter.
-
total_count_change
¶ int – Change in total_count since the last time the listener was called or status was read.
-
current_count
¶ int – The current number of DataWriters matched to the DataReader.
-
current_count_change
¶ int – Change in current_count since the last time the listener was called or status was read.
-
last_publication_handle
¶ dds.core.QosPolicyId
– The handle of the most recent matched DataWriter
-
-
class
dds.core.
Time
¶ Bases:
object
Represents a point in time
Parameters: - sec – an integer seconds value (default: 0)
- nanosec – an integer nanoseconds value (default: 0)
-
exception
dds.core.
Unsupported
¶ Bases:
dds.core.Error
Unsupported operation invoked
-
class
dds.core.
ViewState
¶ ViewState indicates the ‘viewed’ state of a data sample.
The following values are defined:
- NEW_VIEW_STATE
- NOT_NEW_VIEW_STATE
- ANY_VIEW_STATE