MQTT初步使用

环境搭建

　　1、mosquitto所需要的rpm包

　　2、c-ares-1.12.0

　　3、安装最新的openssl版本

　　4、mosquitto-1.4.10

mosquitto需要的rpm包

　　

c-ares安装

c-ares源码下载

./buildconf　　　　#提示libtoolize not found.  需要安装libtool,autoconf,automake
./configure
make
make install

用最新的openssl

编译mosquitto提示出错，‘EC_KEY’ undeclared 
代码不支持老的openssl，所以宏定义提示找不到。
使用openssl-OpenSSL_1_1_0.zip版本

 $ ./config
 $ make
 $ make install

代码不支持老的openssl，所以宏定义提示找不到。
使用openssl-OpenSSL_1_1_0.zip版本
其他程序会用到旧版的openssl，拷贝新的/usr/local/lib/libssl、/usr/local/lib/libcrypto到 /usr/lib/满足兼容

mosquitto使用

编译

make  binary    #只编译二进制文件，不编译man，否则会提示xml错误
src目录下生成mosquitto代理服务器
client目录下生成mosquitto_pub、mosquitto_sub 发布/订阅端。

编译出错一

: Error: Invalid user 'mosquitto'.  错误提示

编译出错二

warning: failed to load external entity "/usr/share/xml/docbook/stylesheet/docbook-xsl/manpages/docbook.xsl"
compilation error: file manpage.xsl line  element import
xsl:import : unable to load /usr/share/xml/docbook/stylesheet/docbook-xsl/manpages/docbook.xsl
compilation error: file mosquitto..xml line  element refentry

解决出错一

adduser mosquitto

解决出错二

yum install  docbook-style-xsl
修改 ./man/manpage.xsl第三行
href="/usr/share/sgml/docbook/xsl-stylesheets-1.75.2/manpages/docbook.xsl"/>

运行/client/mosquitto_pub -t sex -m woman  之后
mosquitto 代理端打印：

[root@localhost src]# ./mosquitto -v
: mosquitto version 1.4. (build date -- ::-) starting
: Using default config.
: Opening ipv4 listen socket on port .
: Opening ipv6 listen socket on port .
: New connection from :: on port .
: New client connected from :: as mosqpub/-localhost (c1, k60).
: Sending CONNACK to mosqpub/-localhost (, )
: Received PUBLISH from mosqpub/-localhost (d0, q0, r0, m0, 'sex', ... (5 bytes))
: Received DISCONNECT from mosqpub/-localhost
: Client mosqpub/-localhost disconnected.

运行/client/mosquitto_sub -t sex  之后
mosquitto 代理端打印：

: New connection from :: on port .
: New client connected from :: as mosqsub/-localhost (c1, k60).
: Sending CONNACK to mosqsub/-localhost (, )
: Received SUBSCRIBE from mosqsub/-localhost
:     sex (QoS )
: mosqsub/-localhost  sex
: Sending SUBACK to mosqsub/-localhost

mosquitto_sub 端收到订阅的消息：

[root@localhost client]# ./mosquitto_sub -v -t sex
sex woman

待续

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