Introduction
Integrate the streaming so your application can receive updates about connected devices in close to real-time, without having to query the Energy Hub Alliance API repeatedly.
Once an energy device or service (vehicle, tariff, HVAC) has been successfully connected to the Energy Hub Alliance, it generates streaming messages that can be received by connecting your application to the streaming service. As of now, the streaming technology supported is Kafka.
Traffic between Kafka consumer and EHA Kafka broker is transported via TLS protocol. Additional imposed security measure is SASL protocol that is used for authentication. Therefore, Kafka consumer will have to setup multiple parameters in order to be able to connect to and read notifications from EHA streaming service, more specifically SASL_SSL security protocol is utilized that Kafka supports.
To consume messages you need a Kafka message consumer, the consumer configuration, credentials and your client system to trust the Let’s Encrypt trustchain. The consumer configuration includes the URL of the EHA Broker, the topic name and the credentials. Topics are separated by subscription ID and security policies assure that only you can access your subscriptions.
Every single topic which you can receive notifications from is dedicated to specific subscription. Therefore, you will have to request specific streaming clients credentials per subscription. Once you collect all streaming credentials for subscription you will be able to connect to all its topics.
Streaming credentials are obtained on the Partner Portal.
Authentication
EHA streaming service support OAuth for authentication across all its Kafka topics. EHA Kafka broker support SASL/OAUTHBEARER authentication, a SASL-based mechanism for authenticating clients using OAuth tokens based on the Java Web Token (JWT) standard, specified in RFC 7519. You you can use the SASL/OAUTHBEARER mechanism to authenticate your Kafka clients.