The Teonet Messages Queue is a part of the Teonet network.
A message queue is a form of asynchronous service-to-service communication used in serverless and microservices architectures. Messages are stored on the queue until they are processed and deleted. Each message is processed only once, by a single consumer. Message queues can be used to decouple heavyweight processing, to buffer or batch work, and to smooth spiky workloads.
The basic teomq scheme works like load balancer between Producers and Consumers.
The Teonet Messages Queue contains three basic parts:
- Teonet messages broker
- Teonet messages consumer
- Teonet messages producer
The Teonet messages Broker is responsible for sending and receiving messages from the Teonet network. It wait connections from message Consumers and messages Producers.
The Consumer connect to Broker and waits for messages from Broker.
The message Producer sends messages to the Broker. Broker add messages to queue and send it to first available Consumer.
The message Consumer process the message and send answer to Broker. The Broker remove message from queue and resend answer to Producer.
The is one Broker and several Consumers and Producers.
Many producers and consumers can use the Brokers queue, but each message is processed only once, by a single consumer. For this reason, this messaging pattern is often called one-to-one, or point-to-point, communications.
Start three aplication in three terminals.
First start the Broker:
# Start broker
go run ./cmd/basic/broker/When the Broker starts, it prints his teonet address in the console. This address will be used in the next steps, when you start Consumers and Producers.
The string with address looks like this:
Connected to Teonet, this app address: og71X6Y8TU1Y2W4G9GkUsKmxnvvd9r2vXp2Then start Consumer using Broker address:
# Start consumer
go run ./cmd/basic/consumer/ -broker=og71X6Y8TU1Y2W4G9GkUsKmxnvvd9r2vXp2Then start Producer using Broker address:
# Start producer
go run ./cmd/basic/producer/ -broker=og71X6Y8TU1Y2W4G9GkUsKmxnvvd9r2vXp2How this Basic teomq exsample works:
Producer sends messages to Broker. Broker prints messages in the console, save it to it's queue and resend it to the Consumer if Consumer is connected to Broker.
Consumer receives messages from Broker, prints them in the console and send it back to Broker. Broker resend this answers to Producer.
You can press Ctrl+C on Consumer terminal to stop the application. When Consumer will stoped, Broker will save messages to queue. When you start Consumer again, it will read messages from Brokers queue, process them and send answers.
In command teomq scheme the Teonet Messages Queue consumers subscribes to specific commands (or events).