十二、消息服务（2）

本章概要

• AMQP
• 安装 RabbitMQ

12.2.1 AMQP 简介

AMQP （Advanced Message Queuing Protocol，高级消息队列协议），是一个线路层的协议规范，而不是 API 规范（例如 JMS）。由于 AMQP 是一个线路层协议规范，因此它天然就是跨平台的，就像 SMTP、HTTP 等协议一样，只要开发者按照规范的格式发送数据，任何平台都可以通过 AMQP 进行消息交互。像目前流行的 StormMQ 、RabbitMQ 等都实现了 AMQP 。

12.2.2 Spring Boot 整合 AMQP

和 JMS 一样，使用 AMQP 也是使用 AMQP 的某个实现，此处以 RabbitMQ 为例介绍 AMQP 的使用。

1. RabbitMQ 简介

RabbitMQ 是一个实现了 AMQP 的开源消息中间件，使用高性能的 Erlang 编写。RabbitMQ 具有可靠性、支持多协议、高可用、支持消息集群以及多语言客户端等特点，在分布式系统中存储转发消息，具有不错的性能表现。

2. RabbitMQ 安装

由于 RabbitMQ 使用 Erlang 编写，因此需要先安装 Erlang 环境，在 CentOS 7 中安装 Erlang 21.0 的步骤如下（其它下载地址：otp_src_21.0.tar.gz）：
（1）下载解压安装包

wget http://erlang.org/download/otp_src_21.0.tar.gz
tar -zxvf /opt/package/otp_src_21.0.tar.gz -C /opt/soft/
1
2

（2）编译

./otp_build autoconf
./configure
1
2

报错了以下错误

configure: error: No curses library functions found
configure: error: /opt/soft/otp_src_21.0/erts/configure failed for erts
1
2

解决方案（没报错不需要）

yum -y install ncurses-devel
./otp_build autoconf
./configure
1
2
3

（3）安装校验

make install
erl
1
2

看到以下内容表示 Erlang 安装成功

[root@VM-12-5-centos otp_src_21.0]# erl
Erlang/OTP 21 [erts-10.0] [source] [64-bit] [smp:1:1] [ds:1:1:10] [async-threads:1] [hipe]

Eshell V10.0  (abort with ^G)
1> 
1
2
3
4
5

Erlang 安装成功后，然后开始安装 RabbitMQ
（1）下载安装文件

wget https://dl.bintray.com/rabbitmq/all/rabbitmq-server/3.7.7/rabbitmq-server-3.7.7.el7.noarch.rpm
1

如果提示502，在此下载：erlang-21.0.9-1.el7，rabbitmq-server-3.7.7-1.el7，还是502，直接离线安装吧：rabbitmq-server-generic-unix-3.7.7.tar

（2）解压

tar -xvf /opt/package/rabbitmq-server-generic-unix-3.7.7.tar -C /opt/soft/
1

修改主机名：vim /etc/hosts，追加一行 127.0.0.1 VM-12-5-centos（VM-12-5-centos改为自己的主机名），因为RabbitMQ在启动的时候会ping自己的主机名，所以这里要进行映射，然后重启网络：service network restart

（3）启动

注意：启动的时候注意查看日志（tail -f /opt/soft/rabbitmq_server-3.7.7/var/log/rabbitmq/log/crash.log）
我这报错了，原因是端口被占用

查看端口占用信息：**lsof -i:5672，然后 kill 掉，kill -9 3918

/opt/soft/rabbitmq_server-3.7.7/sbin/rabbitmq-server start
1

（3）查看状态

/opt/soft/rabbitmq_server-3.7.7/sbin/rabbitmqctl status
1

Status of node rabbit@VM-12-5-centos ...
[{pid,17978},
 {running_applications,
     [{rabbitmq_management,"RabbitMQ Management Console","3.7.7"},
      {rabbitmq_management_agent,"RabbitMQ Management Agent","3.7.7"},
      {rabbitmq_web_dispatch,"RabbitMQ Web Dispatcher","3.7.7"},
      {rabbit,"RabbitMQ","3.7.7"},
      {amqp_client,"RabbitMQ AMQP Client","3.7.7"},
      {rabbit_common,
          "Modules shared by rabbitmq-server and rabbitmq-erlang-client",
          "3.7.7"},
      {recon,"Diagnostic tools for production use","2.3.2"},
      {cowboy,"Small, fast, modern HTTP server.","2.2.2"},
      {ranch_proxy_protocol,"Ranch Proxy Protocol Transport","1.5.0"},
      {ranch,"Socket acceptor pool for TCP protocols.","1.5.0"},
      {ssl,"Erlang/OTP SSL application","9.0"},
      {public_key,"Public key infrastructure","1.6"},
      {asn1,"The Erlang ASN1 compiler version 5.0.6","5.0.6"},
      {os_mon,"CPO  CXC 138 46","2.4.5"},
      {jsx,"a streaming, evented json parsing toolkit","2.8.2"},
      {mnesia,"MNESIA  CXC 138 12","4.15.4"},
      {xmerl,"XML parser","1.3.17"},
      {cowlib,"Support library for manipulating Web protocols.","2.1.0"},
      {crypto,"CRYPTO","4.3"},
      {inets,"INETS  CXC 138 49","7.0"},
      {lager,"Erlang logging framework","3.6.3"},
      {goldrush,"Erlang event stream processor","0.1.9"},
      {compiler,"ERTS  CXC 138 10","7.2"},
      {syntax_tools,"Syntax tools","2.1.5"},
      {syslog,"An RFC 3164 and RFC 5424 compliant logging framework.","3.4.2"},
      {sasl,"SASL  CXC 138 11","3.2"},
      {stdlib,"ERTS  CXC 138 10","3.5"},
      {kernel,"ERTS  CXC 138 10","6.0"}]},
 {os,{unix,linux}},
 {erlang_version,
     "Erlang/OTP 21 [erts-10.0] [source] [64-bit] [smp:1:1] [ds:1:1:10] [async-threads:64] [hipe]\n"},
 {memory,
     [{connection_readers,0},
      {connection_writers,0},
      {connection_channels,0},
      {connection_other,2820},
      {queue_procs,0},
      {queue_slave_procs,0},
      {plugins,799300},
      {other_proc,29727876},
      {metrics,195020},
      {mgmt_db,153256},
      {mnesia,73104},
      {other_ets,2823312},
      {binary,88784},
      {msg_index,31152},
      {code,23237767},
      {atom,1131721},
      {other_system,10672784},
      {allocated_unused,8706880},
      {reserved_unallocated,0},
      {strategy,rss},
      {total,[{erlang,68936896},{rss,73388032},{allocated,77643776}]}]},
 {alarms,[]},
 {listeners,[{clustering,25672,"::"},{amqp,5672,"::"},{http,15672,"::"}]},
 {vm_memory_calculation_strategy,rss},
 {vm_memory_high_watermark,0.4},
 {vm_memory_limit,770865561},
 {disk_free_limit,50000000},
 {disk_free,38876147712},
 {file_descriptors,
     [{total_limit,99901},
      {total_used,2},
      {sockets_limit,89908},
      {sockets_used,0}]},
 {processes,[{limit,1048576},{used,376}]},
 {run_queue,1},
 {uptime,118},
 {kernel,{net_ticktime,60}}]
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74

（4）开启web插件

/opt/soft/rabbitmq_server-3.7.7/sbin/rabbitmq-plugins enable rabbitmq_management
1

（5）重启

/opt/soft/rabbitmq_server-3.7.7/sbin/rabbitmq-server restart
1

（6）添加一个用户名为 long，密码为 123 的用户

/opt/soft/rabbitmq_server-3.7.7/sbin/rabbitmqctl add_user long 123
1

（7）设置 long 用户的角色为管理员

/opt/soft/rabbitmq_server-3.7.7/sbin/rabbitmqctl set_user_tags long administrator
1

（8）配置 long 的权限

/opt/soft/rabbitmq_server-3.7.7/sbin/rabbitmqctl  set_permissions -p / long '.*' '.*' '.*'
1

（9）登录
浏览器访问：http://ip:15672

登录 long 用户