Abstract: The present invention extends to methods, systems, and computer program products for configuring assurances within distributed messaging systems. A defined set of message log and cursor components are configurably activatable and deactivatable to compose a variety of different capture assurances, transfer assurances, and delivery assurances within a distributed messaging system. A composition of a capture assurance, a transfer assurance, and a delivery assurance can provide an end-to-end assurance for a messaging system. End-to-end assurances can include one of best effort, at-most-once, at-least-once, and exactly once and can include one of: durable or non-durable. Using a defined set of activatable and deactivatable message log and cursor components facilities more efficient transitions between desired assurances. In some embodiments, a composition of a capture assurance, a transfer assurance, and a delivery assurance provides durable exactly-once message delivery.

Abstract: The present invention extends to methods, systems, and computer program products for durable exactly once message delivery at scale. A message capture system uses a synchronous capture channel and transactions to provide durable exactly once message capture. Messages are sent from the message capture system to a message delivery system over a network using an at least once transfer protocol. The message delivery system implements a durable at most once messaging behavior, the combination of which results in durable exactly once transfer of messages from the message capture system to the message delivery system. The message delivery system uses a synchronous delivery channel and transactions to provide durable exactly once message delivery. Cursors maintaining message consumer state are collocated with message consumers, freeing up message log resources to process increased volumes of messages, such as, for example, in a queued or pub/sub environment.

Abstract: The present invention extends to methods, systems, and computer program products for maintaining message state at a cursor. A message consumer requests messages from a cursor. The cursor can maintain state information for the message consumers separately from a message log that stores messages. Any of a variety of message delivery assurances can be used when delivering a message to a message consumer.

Abstract: The present invention extends to methods, systems, and computer program products for maintaining message state at a message log. Messages are accumulated at a message log in accordance with a message retention policy. Any of a variety of message capture assurances can be used when capturing a message from a message producer within a message log. A message becomes visible to message consumers after the outcome of writing the message is known (either failure or success). Messages are requested using (e.g., monotonically increasing) sequence numbers. Messages are also dropped from the message log in accordance with the message retention policy.

Abstract: The present invention extends to methods, systems, and computer program products for maintaining message state at a message log. Messages are accumulated at a message log in accordance with a message retention policy. Any of a variety of message capture assurances can be used when capturing a message from a message producer within a message log. A message becomes visible to message consumers after the outcome of writing the message is known (either failure or success). Messages are requested using (e.g., monotonically increasing) sequence numbers. Messages are also dropped from the message log in accordance with the message retention policy.

Abstract: The present invention extends to methods, systems, and computer program products for durable exactly once message delivery at scale. A message capture system uses a synchronous capture channel and transactions to provide durable exactly once message capture. Messages are sent from the message capture system to a message delivery system over a network using an at least once transfer protocol. The message delivery system implements a durable at most once messaging behavior, the combination of which results in durable exactly once transfer of messages from the message capture system to the message delivery system. The message delivery system uses a synchronous delivery channel and transactions to provide durable exactly once message delivery. Cursors maintaining message consumer state are collocated with message consumers, freeing up message log resources to process increased volumes of messages, such as, for example, in a queued or pub/sub environment.

Abstract: The present invention extends to methods, systems, and computer program products for configuring assurances within distributed messaging systems. A defined set of message log and cursor components are configurably activatable and deactivatable to compose a variety of different capture assurances, transfer assurances, and delivery assurances within a distributed messaging system. A composition of a capture assurance, a transfer assurance, and a delivery assurance can provide an end-to-end assurance for a messaging system. End-to-end assurances can include one of best effort, at-most-once, at-least-once, and exactly once and can include one of: durable or non-durable. Using a defined set of activatable and deactivatable message log and cursor components facilities more efficient transitions between desired assurances. In some embodiments, a composition of a capture assurance, a transfer assurance, and a delivery assurance provides durable exactly-once message delivery.

Abstract: The present invention extends to methods, systems, and computer program products for maintaining message state at a cursor. A message consumer requests messages from a cursor. The cursor can maintain state information for the message consumers separately from a message log that stores messages. Any of a variety of message delivery assurances can be used when delivering a message to a message consumer.