RabbitMQ 路由与分发

本页结论：消息永远先到达 Exchange，再由 Binding 决定进入哪些队列；五种 Exchange 类型的路由差异决定了竞争消费、广播与模式匹配三种分发形态。

适用场景

任务分发（一个队列、多个竞争消费者）。
事件广播（一条事件复制给多个独立订阅）。
按业务键路由（地区、租户、事件子类型）。

核心模型：Exchange → Binding → Queue

同一条消息可以进入多个队列 → 各队列的订阅者都能收到（广播）。
同一个队列的多个消费者 → 每条消息只给其中一个（竞争消费，Work Queue）。
广播与竞争消费可以同时存在：先复制到队列，再在队列内竞争。

五种 Exchange 的路由差异

类型	路由依据	典型用法
Default（匿名，""）	routing key = 队列名，直接投递	本仓库 basic / retry-dlq 实验用它
Direct	routing key 与 binding key 完全相等	按明确类别分发，如 `order.created`
Topic	routing key 按段匹配，`*` 一段、`#` 零或多段	层级事件路由，本仓库 routing 实验
Fanout	忽略 routing key，投给全部绑定队列	纯广播
Headers	按消息 headers 键值匹配（x-match=all/any）	少用：性能差、难维护，多数场景 Topic 可替代

Topic 匹配要点（routing 实验验证）

binding	命中 `order.created`	命中 `order.created.eu`
`order.created`	是	否
`order.#`	是	是
`order.created.eu`	否	是

# 可匹配零段：order.# 也能命中 order。绑定 # 的队列会收到所有消息，常用作审计/全量订阅。

动手验证：

bash

bash demos/rabbitmq/routing/run.sh

三队列分别收到 2/3/1 条，与上表一致。

rabbitmq / routingbash demos/rabbitmq/routing/run.sh

assert.out.txt

PASS confirmed: 3
PASS received:orders.routing.created: 2
PASS unique:orders.routing.created: 2
PASS depthAfter:orders.routing.created: 0
PASS received:orders.routing.all: 3
PASS unique:orders.routing.all: 3
PASS depthAfter:orders.routing.all: 0
PASS received:orders.routing.eu: 1
PASS unique:orders.routing.eu: 1
PASS depthAfter:orders.routing.eu: 0
RESULT: all assertions passed

consumer-all.out.txt

SLF4J: Failed to load class "org.slf4j.impl.StaticLoggerBinder".
SLF4J: Defaulting to no-operation (NOP) logger implementation
SLF4J: See http://www.slf4j.org/codes.html#StaticLoggerBinder for further details.
[consumer] timestamp=2026-10-07T10:26:58.311881368Z level=INFO service=order-service product=rabbitmq lab=routing messageId=01JMQ000000000000000000001 eventType=order.created schemaVersion=1 aggregateId=order-1001 traceId=00000000000000000000000000000001 correlationId=order-1001 destination=orders.routing.all consumer=consumer-1 attempt=1 redelivered=false status=received
[replay-gate] timestamp=2026-10-07T10:26:58.336127392Z checkpoint=after-delivery messageId=01JMQ000000000000000000001 token=54a978db2b34-1-after-delivery-01JMQ000000000000000000001-1 status=waiting
[replay-gate] timestamp=2026-10-07T10:27:00.949453933Z checkpoint=after-delivery messageId=01JMQ000000000000000000001 token=54a978db2b34-1-after-delivery-01JMQ000000000000000000001-1 status=released
[consumer] timestamp=2026-10-07T10:27:00.964272955Z level=INFO service=order-service product=rabbitmq lab=routing messageId=01JMQ000000000000000000001 eventType=order.created schemaVersion=1 aggregateId=order-1001 traceId=00000000000000000000000000000001 correlationId=order-1001 destination=orders.routing.all attempt=1 status=business_committed
[replay-gate] timestamp=2026-10-07T10:27:00.964897400Z checkpoint=before-ack messageId=01JMQ000000000000000000001 token=54a978db2b34-1-before-ack-01JMQ000000000000000000001-2 status=waiting
[replay-gate] timestamp=2026-10-07T10:27:05.073793367Z checkpoint=before-ack messageId=01JMQ000000000000000000001 token=54a978db2b34-1-before-ack-01JMQ000000000000000000001-2 status=released
[consumer] timestamp=2026-10-07T10:27:05.076470657Z level=INFO service=order-service product=rabbitmq lab=routing messageId=01JMQ000000000000000000002 eventType=order.created schemaVersion=1 aggregateId=order-1002 traceId=00000000000000000000000000000002 correlationId=order-1002 destination=orders.routing.all consumer=consumer-1 attempt=1 redelivered=false status=received
[replay-gate] timestamp=2026-10-07T10:27:05.077165765Z checkpoint=after-delivery messageId=01JMQ000000000000000000002 token=54a978db2b34-1-after-delivery-01JMQ000000000000000000002-3 status=waiting
[replay-gate] timestamp=2026-10-07T10:27:07.882468119Z checkpoint=after-delivery messageId=01JMQ000000000000000000002 token=54a978db2b34-1-after-delivery-01JMQ000000000000000000002-3 status=released
[consumer] timestamp=2026-10-07T10:27:07.885073322Z level=INFO service=order-service product=rabbitmq lab=routing messageId=01JMQ000000000000000000002 eventType=order.created schemaVersion=1 aggregateId=order-1002 traceId=00000000000000000000000000000002 correlationId=order-1002 destination=orders.routing.all attempt=1 status=business_committed
[replay-gate] timestamp=2026-10-07T10:27:07.885623129Z checkpoint=before-ack messageId=01JMQ000000000000000000002 token=54a978db2b34-1-before-ack-01JMQ000000000000000000002-4 status=waiting
[replay-gate] timestamp=2026-10-07T10:27:10.489919362Z checkpoint=before-ack messageId=01JMQ000000000000000000002 token=54a978db2b34-1-before-ack-01JMQ000000000000000000002-4 status=released
[consumer] timestamp=2026-10-07T10:27:10.491775880Z level=INFO service=order-service product=rabbitmq lab=routing messageId=01JMQ000000000000000000003 eventType=order.created schemaVersion=1 aggregateId=order-1003 traceId=00000000000000000000000000000003 correlationId=order-1003 destination=orders.routing.all consumer=consumer-1 attempt=1 redelivered=false status=received
[replay-gate] timestamp=2026-10-07T10:27:10.492799924Z checkpoint=after-delivery messageId=01JMQ000000000000000000003 token=54a978db2b34-1-after-delivery-01JMQ000000000000000000003-5 status=waiting
[replay-gate] timestamp=2026-10-07T10:27:13.197307122Z checkpoint=after-delivery messageId=01JMQ000000000000000000003 token=54a978db2b34-1-after-delivery-01JMQ000000000000000000003-5 status=released
[consumer] timestamp=2026-10-07T10:27:13.199889028Z level=INFO service=order-service product=rabbitmq lab=routing messageId=01JMQ000000000000000000003 eventType=order.created schemaVersion=1 aggregateId=order-1003 traceId=00000000000000000000000000000003 correlationId=order-1003 destination=orders.routing.all attempt=1 status=business_committed
[replay-gate] timestamp=2026-10-07T10:27:13.200450166Z checkpoint=before-ack messageId=01JMQ000000000000000000003 token=54a978db2b34-1-before-ack-01JMQ000000000000000000003-6 status=waiting
[replay-gate] timestamp=2026-10-07T10:27:16.004987424Z checkpoint=before-ack messageId=01JMQ000000000000000000003 token=54a978db2b34-1-before-ack-01JMQ000000000000000000003-6 status=released
[consumer] timestamp=2026-10-07T10:27:16.005668936Z level=INFO service=order-service product=rabbitmq lab=routing queue=orders.routing.all received=3 status=done

consumer-created.out.txt

SLF4J: Failed to load class "org.slf4j.impl.StaticLoggerBinder".
SLF4J: Defaulting to no-operation (NOP) logger implementation
SLF4J: See http://www.slf4j.org/codes.html#StaticLoggerBinder for further details.
[consumer] timestamp=2026-10-07T10:26:58.278084147Z level=INFO service=order-service product=rabbitmq lab=routing messageId=01JMQ000000000000000000001 eventType=order.created schemaVersion=1 aggregateId=order-1001 traceId=00000000000000000000000000000001 correlationId=order-1001 destination=orders.routing.created consumer=consumer-1 attempt=1 redelivered=false status=received
[replay-gate] timestamp=2026-10-07T10:26:58.322788912Z checkpoint=after-delivery messageId=01JMQ000000000000000000001 token=8c3f770628c8-1-after-delivery-01JMQ000000000000000000001-1 status=waiting
[replay-gate] timestamp=2026-10-07T10:27:02.348086193Z checkpoint=after-delivery messageId=01JMQ000000000000000000001 token=8c3f770628c8-1-after-delivery-01JMQ000000000000000000001-1 status=released
[consumer] timestamp=2026-10-07T10:27:02.365020938Z level=INFO service=order-service product=rabbitmq lab=routing messageId=01JMQ000000000000000000001 eventType=order.created schemaVersion=1 aggregateId=order-1001 traceId=00000000000000000000000000000001 correlationId=order-1001 destination=orders.routing.created attempt=1 status=business_committed
[replay-gate] timestamp=2026-10-07T10:27:02.365572909Z checkpoint=before-ack messageId=01JMQ000000000000000000001 token=8c3f770628c8-1-before-ack-01JMQ000000000000000000001-2 status=waiting
[replay-gate] timestamp=2026-10-07T10:27:06.572907840Z checkpoint=before-ack messageId=01JMQ000000000000000000001 token=8c3f770628c8-1-before-ack-01JMQ000000000000000000001-2 status=released
[consumer] timestamp=2026-10-07T10:27:06.576020145Z level=INFO service=order-service product=rabbitmq lab=routing messageId=01JMQ000000000000000000002 eventType=order.created schemaVersion=1 aggregateId=order-1002 traceId=00000000000000000000000000000002 correlationId=order-1002 destination=orders.routing.created consumer=consumer-1 attempt=1 redelivered=false status=received
[replay-gate] timestamp=2026-10-07T10:27:06.576660280Z checkpoint=after-delivery messageId=01JMQ000000000000000000002 token=8c3f770628c8-1-after-delivery-01JMQ000000000000000000002-3 status=waiting
[replay-gate] timestamp=2026-10-07T10:27:11.785700933Z checkpoint=after-delivery messageId=01JMQ000000000000000000002 token=8c3f770628c8-1-after-delivery-01JMQ000000000000000000002-3 status=released
[consumer] timestamp=2026-10-07T10:27:11.788570771Z level=INFO service=order-service product=rabbitmq lab=routing messageId=01JMQ000000000000000000002 eventType=order.created schemaVersion=1 aggregateId=order-1002 traceId=00000000000000000000000000000002 correlationId=order-1002 destination=orders.routing.created attempt=1 status=business_committed
[replay-gate] timestamp=2026-10-07T10:27:11.789163978Z checkpoint=before-ack messageId=01JMQ000000000000000000002 token=8c3f770628c8-1-before-ack-01JMQ000000000000000000002-4 status=waiting
[replay-gate] timestamp=2026-10-07T10:27:14.594159796Z checkpoint=before-ack messageId=01JMQ000000000000000000002 token=8c3f770628c8-1-before-ack-01JMQ000000000000000000002-4 status=released
[consumer] timestamp=2026-10-07T10:27:14.594810609Z level=INFO service=order-service product=rabbitmq lab=routing queue=orders.routing.created received=2 status=done

consumer-eu.out.txt

SLF4J: Failed to load class "org.slf4j.impl.StaticLoggerBinder".
SLF4J: Defaulting to no-operation (NOP) logger implementation
SLF4J: See http://www.slf4j.org/codes.html#StaticLoggerBinder for further details.
[consumer] timestamp=2026-10-07T10:26:58.422093259Z level=INFO service=order-service product=rabbitmq lab=routing messageId=01JMQ000000000000000000003 eventType=order.created schemaVersion=1 aggregateId=order-1003 traceId=00000000000000000000000000000003 correlationId=order-1003 destination=orders.routing.eu consumer=consumer-1 attempt=1 redelivered=false status=received
[replay-gate] timestamp=2026-10-07T10:26:58.439351311Z checkpoint=after-delivery messageId=01JMQ000000000000000000003 token=ed799219e1f1-1-after-delivery-01JMQ000000000000000000003-1 status=waiting
[replay-gate] timestamp=2026-10-07T10:27:03.654337918Z checkpoint=after-delivery messageId=01JMQ000000000000000000003 token=ed799219e1f1-1-after-delivery-01JMQ000000000000000000003-1 status=released
[consumer] timestamp=2026-10-07T10:27:03.667702403Z level=INFO service=order-service product=rabbitmq lab=routing messageId=01JMQ000000000000000000003 eventType=order.created schemaVersion=1 aggregateId=order-1003 traceId=00000000000000000000000000000003 correlationId=order-1003 destination=orders.routing.eu attempt=1 status=business_committed
[replay-gate] timestamp=2026-10-07T10:27:03.668731148Z checkpoint=before-ack messageId=01JMQ000000000000000000003 token=ed799219e1f1-1-before-ack-01JMQ000000000000000000003-2 status=waiting
[replay-gate] timestamp=2026-10-07T10:27:09.180210952Z checkpoint=before-ack messageId=01JMQ000000000000000000003 token=ed799219e1f1-1-before-ack-01JMQ000000000000000000003-2 status=released
[consumer] timestamp=2026-10-07T10:27:09.181625879Z level=INFO service=order-service product=rabbitmq lab=routing queue=orders.routing.eu received=1 status=done

producer.out.txt

SLF4J: Failed to load class "org.slf4j.impl.StaticLoggerBinder".
SLF4J: Defaulting to no-operation (NOP) logger implementation
SLF4J: See http://www.slf4j.org/codes.html#StaticLoggerBinder for further details.
[producer] timestamp=2026-10-07T10:26:56.798983990Z level=INFO service=order-service product=rabbitmq lab=routing messageId=01JMQ000000000000000000001 eventType=order.created schemaVersion=1 aggregateId=order-1001 traceId=00000000000000000000000000000001 correlationId=order-1001 destination=orders.events routingKey=order.created durationMs=3 status=confirmed
[producer] timestamp=2026-10-07T10:26:56.803610344Z level=INFO service=order-service product=rabbitmq lab=routing messageId=01JMQ000000000000000000002 eventType=order.created schemaVersion=1 aggregateId=order-1002 traceId=00000000000000000000000000000002 correlationId=order-1002 destination=orders.events routingKey=order.created durationMs=1 status=confirmed
[producer] timestamp=2026-10-07T10:26:56.805388462Z level=INFO service=order-service product=rabbitmq lab=routing messageId=01JMQ000000000000000000003 eventType=order.created schemaVersion=1 aggregateId=order-1003 traceId=00000000000000000000000000000003 correlationId=order-1003 destination=orders.events routingKey=order.created.eu durationMs=1 status=confirmed
[producer] timestamp=2026-10-07T10:26:56.805523532Z level=INFO service=order-service product=rabbitmq lab=routing destination=orders.events confirmed=3 status=done

setup.out.txt

SLF4J: Failed to load class "org.slf4j.impl.StaticLoggerBinder".
SLF4J: Defaulting to no-operation (NOP) logger implementation
SLF4J: See http://www.slf4j.org/codes.html#StaticLoggerBinder for further details.

负载分发：Prefetch 的作用

多个竞争消费者时，RabbitMQ 默认轮询分发（round-robin）。若不设 Prefetch，Broker 可能一次把大量消息推给单个消费者，导致其他消费者空闲、该消费者积压。正确姿势：

java

channel.basicQos(1); // 未 ACK 消息最多 1 条，处理完再发下一条

本仓库所有 Demo 均设置 prefetch=1，保证「慢消费者不多拿」。

常见误区

「Producer 直接发给队列」——除了 Default Exchange，消息都先经过 Exchange；发到未声明的 Exchange 会关 Channel。
「绑定可以解绑就没事了」——绑定关系本身是持久状态，声明幂等但删除绑定会改变流量走向，变更需当发布对待。
「routing key 就是 eventType」——本仓库约定 routing key 表达路由意图（可与 eventType 一致），队列名不应承载业务语义。
「Fanout + 单队列 = 广播」——广播要求每个订阅者有自己的队列；共用一个队列就退化成竞争消费。

官方资料

Exchanges：https://www.rabbitmq.com/tutorials/amqp-concepts#exchange-direct（checkedAt: 2026-08-19）
Tutorial 5（Topic）：https://www.rabbitmq.com/tutorials/tutorial-five-java（checkedAt: 2026-08-19）
Prefetch：https://www.rabbitmq.com/docs/consumer-prefetch（checkedAt: 2026-08-19）

RabbitMQ 路由与分发 ​

适用场景 ​

核心模型：Exchange → Binding → Queue ​

五种 Exchange 的路由差异 ​

Topic 匹配要点（routing 实验验证） ​

负载分发：Prefetch 的作用 ​

常见误区 ​

官方资料 ​