v4 breaking changes
ChirpStack v4 is a new major version that brings many improvements over the ChirpStack v3. Before you migrate your ChirpStack v3 instance to ChirpStack v4, please be aware that there are changes that are not backwards compatible!
Gateway to ChirpStack MQTT
The ChirpStack Gateway Bridge v3.14.0+ version is compatible with both
ChirpStack v3 and ChirpStack v4, as long as the
protobuf marshaler is
configured (default value). This to eases the migration, as the published
MQTT data can be consumed by both ChirpStack v3 and ChirpStack v4.
Please note that the default ChirpStack v4 configuration contains the region as MQTT prefix in the configuration. This means that you need to either:
- Update the ChirpStack Gateway Bridge topic configurations to include the region in the templates, or
- Update the ChirpStack region configuration, removing the topic prefix from the topic templates, or
- Implement a service which re-publishes MQTT messages, resulting in messages being published both with and without the topic prefix.
Support for using AMQP, GCP Pub/Sub or Azure IoT Hub as gateway backend is not supported by the initial ChirpStack v4 release, but will be added in a future version.
If using the gRPC API, you must upgrade the ChirpStack gRPC API client-libraries to v4. In general, the structure of the gRPC is mostly identical to the v3 gRPC API definition, but there are minor changes and renames. The v3 client-code is not compatible with the v4 API.
API tokens generated using ChirpStack v3 are not compatible with ChirpStack v4. You must generate new tokens (the migration tool will not migrate these tokens).
ChirpStack v3 provided a REST API on top of the gRPC API. This means that REST request were internally translated to gRPC calls and responses back to REST. For this the gRPC Gateway project was used internally. Historically, this component was embedded because of the web-interface. At the time of this implementation, gRPC could not be used within the browser. ChirpStack v4 uses gRPC Web to interface with the gRPC API.
With the recommendation to use the gRPC API directly (to avoid the REST to gRPC translation for each API request) and the web-interface using gRPC Web, ChirpStack v4 no longer provides an embedded REST API interface. However, the ChirpStack project does provide a component to provide a REST interface on top of the ChirpStack gRPC API. Please refer to https://github.com/chirpstack/chirpstack-rest-api.
Integration event messages
The integration event messages have been refactored to provide the same base information for all events. This includes the tenant, application, device-profile and device information (names and ids). Decoded uplink events are directly represented as object, before this was encoded as JSON string. Some fields have been renamed.
ChirpStack v3 contained numeric identifiers for organizations, users,
applications etc. On public instances this could expose some information (e.g. number of users).
In ChirpStack v4 identifiers have been changed to UUIDs. The v3 to v4 migration
utility will migrate numeric identifiers to UUIDs by starting with an empty
00000000-0000-0000-0000-000000000000) and setting the last characters
to the numeric value.
For example, the numeric id
1234 will be migrated to
Network controller interface
ChirpStack v3 provided a
NetworkControllerService which could be implemented
to handle uplink and downlink meta-data. This interface has been removed. This
meta-data can now be logged into a Redis Stream
by setting the
meta_log_max_history to a non-zero value. This log can then be
consumed by an external application.
Custom ADR algorithms
The gateway discovery feature has been removed. The problem is that this is not supported by the Basics Station packet-forwarder (see #26). As well, some gateways have RF filters on the RX and TX path to filter out noise. In regions where the uplink frequencies are not equal to the downlink frequencies, these filters would prevent proper gateway to gateway communication.