Interservice communication via message bus for microservices.
No. Consider this project a WIP.
mimi-messaging is a Messaging layer -- an interservice
communication layer based on message bus, for connecting microservice applications.
- Command, Query, Event communication patterns
- "at-least-once" message delivery guarantees
- Abstract message bus interface, not bound to specific message broker implementation
See also: Overview of Messaging layer properties
When it comes to organizing communications between different microservices of a system, currently there is only two options: to use HTTP or a message bus.
Why HTTP is a bad choice for interservice communication?
TBD: Message bus pro's and con's.
Concepts:
- Command: one-to-one, send and forget
- Query: one-to-one, call and wait for response
- Event: one-to-many, broadcast
gem "mimi-messaging", "~> 1.0"
gem "mimi-messaging-<ADAPTER>"
require "mimi/messaging"
require "mimi/messaging/<ADAPTER>"
Mimi::Messaging.use serializer: Mimi::Messaging::JsonSerializer
Mimi::Messaging.configure mq_adapter: "<ADAPTER>", ... # extra adapter specific options
Mimi::Messaging.start
Producing messages:
# COMMAND
Mimi::Messaging.command("users/lock", id: "b3cc29c8d2ec68e0")
# QUERY
response = Mimi::Messaging.query("orders/show", id: 123)
# EVENT
See (/examples)[/examples] folder for more examples on how to produce and consume messages.
mimi-messaging is not bound to a specific message broker implementation like RabbitMQ or Kafka. It interacts with a message broker using an adapter interface and
there are several available adapters:
- Kafka
- RabbitMQ (TBD)
- NATS (TBD)
- Amazon SQS/SNS
- (in-memory (single process))[lib/mimi/messaging/adapters/memory.rb]
There are only two hard problems in distributed systems:
2. Exactly-once delivery
1. Guaranteed order of messages
2. Exactly-once delivery
Messaging API specification format
The gem is available as open source under the terms of the MIT License.