[](https://crates.io/crates/general-mq)
[](https://docs.rs/general-mq)
[](https://woofdogtw.github.io/sylvia-iot-core/coverage/general-mq/)
[](LICENSE)
# general-mq
General purposed interfaces for message queues. Now we provide the following implementations:
- AMQP 0-9-1
- MQTT
By using these classes, you can configure queues with the following properties:
- Unicast or broadcast.
- Reliable or best-effort.
**Notes**
- MQTT uses **shared queues** to implement unicast.
- AMQP uses **confirm channels** to implement reliable publish, and MQTT uses **QoS 1** to
implement reliable publish/subscribe.
# Relationships of Connections and Queues
The term **connection** describes a TCP/TLS connection to the message broker.
The term **queue** describes a message queue or a topic within a connection.
You can use one connection to manage multiple queues, or one connection to manage one queue.
A queue can only be a receiver or a sender at a time.
### Connections for sender/receiver queues with the same name
The sender and the receiver are usually different programs, there are two connections to hold two
queues.
For the special case that a program acts both the sender and the receiver using the same queue:
- The AMQP implementation uses one **Channel** for one queue, so the program can manages all
queues with one connection.
- The MQTT implementation **MUST** uses one connection for one queue, or both sender and receiver
will receive packets.
# Test
Please prepare a [RabbitMQ](https://www.rabbitmq.com/) broker and a [EMQX](https://emqx.io/)
broker at **localhost** for testing.
- To install using Docker:
$ docker run --rm --name rabbitmq -d -p 5672:5672 rabbitmq:management-alpine
$ docker run --rm --name emqx -d -p 1883:1883 emqx/emqx
Then run the test:
$ cargo test --test integration_test -- --nocapture
# Example
Launch RabbitMQ and then run AMQP example:
$ cargo run --example simple
Launch EMQX and then run MQTT example:
$ RUN_MQTT= cargo run --example simple