我目前正在使用golang（github.com/streadway/amqp）测试rabbitmq，我有三个程序，其中两个程序将消息发送到具有不同优先级的队列和一个从队列中读取的消息。
我遇到的问题是，在用两个程序发送一些消息后，我继续启动将从队列中读取的程序，当它开始从队列中读取时，它会像FIFO一样输出结果。
我希望首先输出高优先级，然后输出优先级较低的消息
我误解了rabbitmq是如何工作的还是我做错了什么？
发送到队列 包主要
import (
"log"
"github.com/streadway/amqp"
)
func failOnError(err error, msg string) {
if err != nil {
log.Fatalf("%s: %s", msg, err)
}
}
func main() {
args := make(amqp.Table)
args["x-max-priority"] = int64(9)
conn, err := amqp.Dial("amqp://guest:guest@localhost:5672/")
failOnError(err, "Failed to connect to RabbitMQ")
defer conn.Close()
ch, err := conn.Channel()
failOnError(err, "Failed to open a channel")
defer ch.Close()
q, err := ch.QueueDeclare(
"test", // name
false, // durable
false, // delete when unused
false, // exclusive
false, // no-wait
args, // arguments
)
failOnError(err, "Failed to declare a queue")
body := "low"
err = ch.Publish(
"", // exchange
q.Name, // routing key
false, // mandatory
false, // immediate
amqp.Publishing{
Headers: amqp.Table{},
ContentType: "text/plain",
ContentEncoding: "",
Body: []byte(body),
DeliveryMode: amqp.Transient, // 1=non-persistent, 2=persistent
Priority: 0,
})
log.Printf(" [x] Sent %s", body)
failOnError(err, "Failed to publish a message")
body = "low"
err = ch.Publish(
"", // exchange
q.Name, // routing key
false, // mandatory
false, // immediate
amqp.Publishing{
Headers: amqp.Table{},
ContentType: "text/plain",
ContentEncoding: "",
Body: []byte(body),
DeliveryMode: amqp.Transient, // 1=non-persistent, 2=persistent
Priority: 0,
})
log.Printf(" [x] Sent %s", body)
failOnError(err, "Failed to publish a message")
body = "low"
err = ch.Publish(
"", // exchange
q.Name, // routing key
false, // mandatory
false, // immediate
amqp.Publishing{
Headers: amqp.Table{},
ContentType: "text/plain",
ContentEncoding: "",
Body: []byte(body),
DeliveryMode: amqp.Transient, // 1=non-persistent, 2=persistent
Priority: 0,
})
log.Printf(" [x] Sent %s", body)
failOnError(err, "Failed to publish a message")
body = "high"
err = ch.Publish(
"", // exchange
q.Name, // routing key
false, // mandatory
false, // immediate
amqp.Publishing{
Headers: amqp.Table{},
ContentType: "text/plain",
ContentEncoding: "",
Body: []byte(body),
DeliveryMode: amqp.Transient, // 1=non-persistent, 2=persistent
Priority: 9,
})
log.Printf(" [x] Sent %s", body)
failOnError(err, "Failed to publish a message")
body = "low"
err = ch.Publish(
"", // exchange
q.Name, // routing key
false, // mandatory
false, // immediate
amqp.Publishing{
Headers: amqp.Table{},
ContentType: "text/plain",
ContentEncoding: "",
Body: []byte(body),
DeliveryMode: amqp.Transient, // 1=non-persistent, 2=persistent
Priority: 0,
})
log.Printf(" [x] Sent %s", body)
failOnError(err, "Failed to publish a message")
body = "low"
err = ch.Publish(
"", // exchange
q.Name, // routing key
false, // mandatory
false, // immediate
amqp.Publishing{
Headers: amqp.Table{},
ContentType: "text/plain",
ContentEncoding: "",
Body: []byte(body),
DeliveryMode: amqp.Transient, // 1=non-persistent, 2=persistent
Priority: 0,
})
log.Printf(" [x] Sent %s", body)
failOnError(err, "Failed to publish a message")
body = "low"
err = ch.Publish(
"", // exchange
q.Name, // routing key
false, // mandatory
false, // immediate
amqp.Publishing{
Headers: amqp.Table{},
ContentType: "text/plain",
ContentEncoding: "",
Body: []byte(body),
DeliveryMode: amqp.Transient, // 1=non-persistent, 2=persistent
Priority: 0,
})
log.Printf(" [x] Sent %s", body)
failOnError(err, "Failed to publish a message")
}
阅读队列：
package main
import (
"log"
"github.com/streadway/amqp"
)
func failOnError(err error, msg string) {
if err != nil {
log.Fatalf("%s: %s", msg, err)
}
}
func main() {
args := make(amqp.Table)
args["x-max-priority"] = int64(9)
conn, err := amqp.Dial("amqp://guest:guest@localhost:5672/")
failOnError(err, "Failed to connect to RabbitMQ")
ch, err := conn.Channel()
failOnError(err, "Failed to open a channel")
q, err := ch.QueueDeclare(
"test", // name
false, // durable
false, // delete when unused
false, // exclusive
false, // no-wait
args, // arguments
)
failOnError(err, "Failed to declare a queue")
msgs, err := ch.Consume(
q.Name, // queue
"", // consumer
true, // auto-ack
false, // exclusive
false, // no-local
false, // no-wait
args, // args
)
failOnError(err, "Failed to register a consumer")
defer ch.Close()
defer conn.Close()
forever := make(chan bool)
go func() {
for d := range msgs {
log.Printf("Received a message: %s", d.Body)
}
}()
log.Printf(" [*] Waiting for messages. To exit press CTRL+C")
<-forever
}
首先，我启动将消息发送到队列的代码：
low条消息的优先级为0，high的优先级为9
然后我启动将接收队列的程序
预期产出：
实际输出：
谢谢
答案 0 :(得分：0)
这是我可以从您的代码中找到的，以及您所遵循的步骤的描述。
似乎问题是你没有在每段代码中以相同的方式创建队列，低优先级和高优先级的生成器创建没有x-max-priority参数的队列。
由于队列在创建时被定义为优先级队列，并且仅在那时，您实际创建了一个＆＃34;标准＆＃34;队列中。
您应该能够轻松确认此检查已创建的队列及其参数。
答案 1 :(得分：0)
我更新到最新的rabbitmq并且它有效，我不知道这是否是唯一的解决方案。
除了callign ch.Qos(1, 0, false)之外，我还需要删除auto-ack并在之后手动确认该消息，以便它不会确认队列中的所有消息。