Eclipse Hono 1.5.0

This minor release introduces the following new features

• The CoAP adapter has been promoted from experimental to fully supported.
• The Hono Client now supports several configuration properties that can be used to limit its resource usage. In particular the AMQP connection's max-frame-size, the AMQP session's incoming window size and the max-message-size of receiver links can be configured (and thus limited).
• A new Hono Clients component has been added which provides use case specific modules that can be used to access Hono's APIs in a transport protocol agnostic way. The (legacy) client implicitly assumes that the transport protocol being used is AMQP 1.0. In an attempt to support Apache Kafka as an alternative to the AMQP 1.0 Messaging Network for sending messages downstream, a new set of Java client interfaces has been created which make no assumption regarding the underlying transport protocol. The initial implementation of these interfaces is based on the legacy client using AMQP 1.0. In future versions, a Kafka client based implementation will be added.
• A new way of routing Command & Control messages from the AMQP messaging network to the target protocol adapters has been introduced. For that, a new Command Router service component is used, receiving command messages and routing them to the appropriate protocol adapters. Protocol adapters supply routing information to the component by means of a new Command Router API. Protocol adapters can be configured to either use that new API or they can continue using the now deprecated Device Connection API instead, meaning command routing will be done without using the Command Router.