ark::pipeline::Envelope

Defined in header “ark/pipeline/envelope.hh”.

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An envelope wraps messages that are published, recording a publish time, and supporting an abstraction to make it easier to serialize messages without knowing their type.

These are typically created automatically by the publisher.

Methods

• Envelope(std::shared_ptr< const Type > payload, TimeType publish_time, uint64_t sequence_number, uint64_t publisher_identifier)
  Constructor. Initializes a new message against the given payload and with the specified capture time. Uses the default publisher identifier(0) if none is provided.

• ~Envelope()
  Virtual destructor, for cleanup.

• std::shared_ptr< const Type > payload()
  Returns the payload (raw message type).

• const TimeType & publish_time()
  Returns the time that this object was published.

• uint64_t publisher_sequence_number()
  Returns the sequence number of this message with respect to messages published from a single publisher. In other words, if publisher ID is identical between envelopes, you should see this number increment monotnically.

• uint64_t publisher_identifier()
  Returns the identifier of the publisher that constructed this envelope. You should not depend on this value to be unique or consistent across executions.

• serialization::JsonBlob to_json()
  Deserializes the given internal type as a JSON object. This will throw if the type isn’t serializable.

• core::ByteBuffer to_bytes()
  Deserializes the internal type as a byte buffer, using binary serialization.

• const std::type_info & message_type()
  Returns type identification information about the payload inside this envelope.

• std::string message_type_name()
  Returns a string-form of the type identification information about the payload inside the envelope.

• bool is_serializable()
  Returns true if the type that this envelopes contains identifies as being serializable.