github.com/robinjoseph08/redisqueue

redisqueue

redisqueue provides a producer and consumer of a queue that uses Redis streams.

Features

• A Producer struct to make enqueuing messages easy.
• A Consumer struct to make processing messages concurrenly.
• Claiming and acknowledging messages if there's no error, so that if a consumer dies while processing, the message it was working on isn't lost. This guarantees at least once delivery.
• A "visibility timeout" so that if a message isn't processed in a designated time frame, it will be be processed by another consumer.
• A max length on the stream so that it doesn't store the messages indefinitely and run out of memory.
• Graceful handling of Unix signals (SIGINT and SIGTERM) to let in-flight messages complete.
• A channel that will surface any errors so you can handle them centrally.
• Graceful handling of panics to avoid crashing the whole process.
• A concurrency setting to control how many goroutines are spawned to process messages.
• A batch size setting to limit the total messages in flight.
• Support for multiple streams.

Example

Here's an example of a producer that inserts 1000 messages into a queue:

package main

import (
	"fmt"

	"github.com/robinjoseph08/redisqueue"
)

func main() {
	p, err := redisqueue.NewProducerWithOptions(&redisqueue.ProducerOptions{
		StreamMaxLength:      10000,
		ApproximateMaxLength: true,
	})
	if err != nil {
		panic(err)
	}

	for i := 0; i < 1000; i++ {
		err := p.Enqueue(&redisqueue.Message{
			Stream: "redisqueue:test",
			Values: map[string]interface{}{
				"index": i,
			},
		})
		if err != nil {
			panic(err)
		}

		if i%100 == 0 {
			fmt.Printf("enqueued %d\n", i)
		}
	}
}

And here's an example of a consumer that reads the messages off of that queue:

package main

import (
	"fmt"
	"time"

	"github.com/robinjoseph08/redisqueue"
)

func main() {
	c, err := redisqueue.NewConsumerWithOptions(&redisqueue.ConsumerOptions{
		VisibilityTimeout: 60 * time.Second,
		BlockingTimeout:   5 * time.Second,
		ReclaimInterval:   1 * time.Second,
		BufferSize:        100,
		Concurrency:       10,
	})
	if err != nil {
		panic(err)
	}

	c.Register("redisqueue:test", process)

	go func() {
		for err := range c.Errors {
			// handle errors accordingly
			fmt.Printf("err: %+v\n", err)
		}
	}()

	fmt.Println("starting")
	c.Run()
	fmt.Println("stopped")
}

func process(msg *redisqueue.Message) error {
	fmt.Printf("processing message: %v\n", msg.Values["index"])
	return nil
}