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This minor release introduces the following new features
The Sigfox and LoRaWAN adapters now report metrics analogously to the other protocol adapters.
With the release of Eclipse Californium 2.0.0, the CoAP adapter became an official part of the Hono release. The adapter also supports tracking of request processing using OpenTracing but is still considered experimental.
A lorawan provider has been added for the loriot network provider.
Hono's protocol adapters now support Server Name Indication in order to allow devices to establish a TLS connection with adapters using a tenant specific server certificate and host name.
Hono now supports auto-provisioning of devices that authenticate with X.509 client certificates. This way, devices do not need to be manually registered one-by-one but can be provisioned on-the-fly when they first connect to one of Hono's protocol adapters.
The Hono Auth Server and Device Registry components now support configuring the SASL mechanisms advertised to a client connecting to these components. This can be used to restrict the support to only one of the SASL PLAIN and EXTERNAL mechanisms instead of both.
A new metric has been introduced to track the connection duration of authenticated devices per tenant. The protocol adapters can use this information to reject new connections from devices of a tenant if the configured overall connection time for the current accounting period has been reached.
Hono's example device registry now supports configuring a time out for processing requests from clients.
The project leadership certifies that the APIs in this release are "Eclipse Quality".
It has always been clear that Hono's external AMQP 1.0 based APIs and the HTTP based Device Registry Management API are public API and thus are subject to semantic versioning.
After quite some discussion the Hono committers have concluded that the Java classes that implement these APIs are not to be considered public API and thus are not subject to semantic versioning. This is due to several facts. First, Hono is not supposed to be used as a library, i.e. users are encouraged to interact with Hono using its remote APIs. Second, subjecting our classes to semantic versioning would slow us down considerably in quickly evolving and improving Hono's inner workings.
That said, users may still use some of Hono's classes in order to e.g. build their own custom protocol adapter. However, they should not expect all classes to remain backwards compatible with each patch/minor update. At some point we might feel comfortable enough to actually define a subset of our classes as public API as well, but we're not there yet.
A lot of discussion has also been going on regarding the question of where to maintain and develop Hono's Helm chart. We had the chart in the Hono code base for quite some time now and created a new version of the chart in sync with each Hono release. However, users had to download the chart from Eclipse mirrors and could then use the Helm client to install Hono. With the advent of the Eclipse IoT Packages project and the Helm chart repository it provides for Eclipse IoT projects, we have decided to move the Helm chart to that repository and do its future development there as well. Users can now simply add the Eclipse IoT Packages repository URL to their Helm client and can then very easily install Hono just by referring to its chart name.
Hono's Helm chart is now available from the Eclipse IoT Packages chart repository which can easily be added to a local Helm client's known repositories. This makes installation of Hono using Helm a lot easier. All future development of the chart will be done in the IoT Packages project only.
The legacy endpoints of the Command & Control API are no longer supported. These endpoints had in fact never been part of Hono's public API because they had already been marked as deprecated in Hono 1.0.0.
The CoAP adapter that is now officially part of Hono is based on Eclipse Californium and as such supports all the RFCs and standards that Californium supports.
By moving Hono's Helm chart to the Eclipse IoT Packages project we have also started work on integrating Hono with Eclipse Ditto an Eclipse hawkBit to form a pre-integrated IoT cloud stack that can be easily installed as a package using Helm and which is supposed to lower the entry barrier for users to get started with these technologies.
We have also started work on integrating Hono with Eclipse ioFog in order to use Hono as the data plane in cloud/edge computing use cases.