MQ Go

A minimalist toy message queuing server that operates over HTTP. Messages are distributed to any clients registered to receive them. No channels, topics, etc are supported.

Usage

1. Run go build .
2. Run mq-go. By default, logging goes to stderr, the server runs on port 8080, a buffer of 5 messages can wait to be distributed at once, and 3 worker threads are spawned.

Flags are:

Usage of ./mq-go:
  -jobs int
    number of buffered send jobs (default 5)
  -port int
    listening port (default 8080)
  -workers int
    number of send worker threads (default 3)

Questions?

Why HTTP?

Because I knew a little bit about how net/http works and TCP protocols seemed like too much work for a quick toy.

Why not use one of the many existing solutions?

Because I was curious and wanted something very simple to experiment with containerization and orchestration.

You wrote this because you're messing with Kubernetes?

Yes, and I didn't also want to add "messing with RabbitMQ" to that.

Can or should I use this software for anything meaningful?

Probably not. As it stands anyone who is able to find the server can send a message. There's minimal rate limiting. There is no authentication. Also, I am not a Go expert so there's no guarantee the code isn't full of worst practices, race conditions, and/or straight-up broken bits.

Client Requests

1. CONNECT: An HTTP POST request to /connect. Establishes as connection. The body should be a JSON document like

{
    "ClientURL": "svc.domain.tld/mqg",
    "mode": "send",
}

The 'mode' key should have one of two values: 'send' or 'receive'. A 'send' value will register the client as a message-submitter. A 'receive' value will register the client to receive messages.

Server Response: 200 OK with body like

{
    "id": 123456,
}

2. SEND: An HTTP POST request to /send. The body of the request should include the message, which is a string, like:

{
    "id": 12346,
    "body": "Here is the message body.",
 }

Server Response: 200 OK with body like

{
    "status": "Message enqueued.",
    "id": 123456
}

The root 'id'key should contain a value that matched a connected sender client.

3. DISCONNECT: An HTTP Post request to /disconnect. The JSON body needs to include the ID of the connection.

{
    "id": 123456
}

Server Response: 200 OK with body like

{
    "id": 123456,
    "message": "Disconnected."
}

Server Requests

1. MESSAGE: An HTTP POST to a client's ClientURL with a body like

{
    "body": "Here is the message body."
}