openresty替换掉nginx并打印response返回内容

0.备份nginx的配置文件

备份 /etc/nginx/nginx.conf 和 /etc/nginx/conf.d/
例如：

cp /etc/nginx/nginx.conf /home/temp/
cp -R  /etc/nginx/conf.d/ /home/temp/

如果有其他路径的配置文件，也需要备份，一切以实际为准！

1.卸载nginx

systemctl disable nginx.service
rm -rf /usr/sbin/nginx
rm -rf /etc/nginx/
yum remove nginx

2.安装openresty

参考 https://openresty.org/cn/

cd /home/temp/
wget https://openresty.org/package/centos/openresty.repo
mv openresty.repo /etc/yum.repos.d/
yum install -y openresty

# 启动openresty里的nginx
openresty 
#或者 /usr/local/openresty/nginx/sbin/nginx

2.1 也可通过压缩包安装

wget https://openresty.org/download/openresty-1.19.3.1.tar.gz
tar xzvf openresty-1.19.3.1.tar.gz
cd openresty-1.19.3.1/ 
./configure
make 
make install

# better also add the following line to your ~/.bashrc or ~/.bash_profile file.
export PATH=/usr/local/openresty/bin:$PATH

默认情况下程序会被安装到 /usr/local/openresty 目录，你可以使用 ./configure --help 查看更多的配置选项。

访问 http://ip 能看到“Welcome to OpenResty!”的界面说明openresty安装并启动成功，如下：

image.png

3.还原nginx配置文件到openresty

1.将 /etc/nginx/nginx.conf 和 /etc/nginx/conf.d 复制到 openresty 的配置文件存放路径 /usr/local/openresty/nginx/conf/ 下。

cp /home/temp/nginx.conf /usr/local/openresty/nginx/conf/
cp -R /home/temp/conf.d/ /usr/local/openresty/nginx/conf/

注意：
nginx默认安装的地址是： /etc/nginx/
openresty默认安装的地址是： /usr/local/openresty/
openresty下的nginx配置路径是：/usr/local/openresty/nginx/conf/
所以需要将 /usr/local/openresty/nginx/conf/nginx.conf 文件中的include配置更改为实际路径：

# 原配置内容
    include /etc/nginx/conf.d/*.conf;


# 更改后的配置内容
    include /usr/local/openresty/nginx/conf/conf.d/*.conf;

读者配置时，以实际路径为准。

2. 重启openresty，验证其代理是否成功

openresty -s reload
# 或者 /usr/local/openresty/nginx/sbin/nginx -s reload

4.添加日志配置，打印response body

1. 编辑/usr/local/openresty/nginx/conf/nginx.conf文件，将log_format更改，

变更前：

    log_format  main  '$remote_addr - $remote_user [$time_local] "$request" '
                      '$status $body_bytes_sent "$http_referer" '
                      '"$http_user_agent" "$http_x_forwarded_for"';

    access_log  /var/log/nginx/access.log  main;

变更后：

    log_format  main  escape=json '{ "@timestamp": "$time_local", '
                         '"remote_addr": "$remote_addr", '
                         '"upstream_addr": "$upstream_addr",'
                         '"remote_user": "$remote_user", '
                         '"body_bytes_sent": "$body_bytes_sent", '
                         '"request_time": "$request_time", '
                         '"status": "$status", '
                         '"request": "$request", '
                         '"request_method": "$request_method", '
                         '"http_referrer": "$http_referer", '
                         '"body_bytes_sent":"$body_bytes_sent", '
                         '"http_x_forwarded_for": "$http_x_forwarded_for", '
                         '"remote_addr":""$remote_addr",'
                         '"http_user_agent": "$http_user_agent",'
                         '"http_uri": "$uri",'
                         '"http_host":"$http_host",'
                         '"resp_body":"$resp_body" }';

    access_log  logs/access.log  main;

2. 在需要监听的配置文件中（如：/usr/local/openresty/nginx/conf/nginx.conf/default.conf），添加如下内容

    lua_need_request_body on;
    set $resp_body "";
    body_filter_by_lua '
        local resp_body = string.sub(ngx.arg[1], 1, 1000)
        ngx.ctx.buffered = (ngx.ctx.buffered or "") .. resp_body
        if ngx.arg[2] then
            ngx.var.resp_body = ngx.ctx.buffered
        end
    ';

示例：

server {
    listen       80;
    server_name  localhost;

    proxy_set_header Host $host;
    proxy_set_header X-Real-IP $remote_addr;
    proxy_set_header X-Real-Port $remote_port;
    proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;

    client_max_body_size  200m;

    lua_need_request_body on;
    set $resp_body "";
    body_filter_by_lua '
        local resp_body = string.sub(ngx.arg[1], 1, 1000)
        ngx.ctx.buffered = (ngx.ctx.buffered or "") .. resp_body
        if ngx.arg[2] then
            ngx.var.resp_body = ngx.ctx.buffered
        end
    ';

    # 根路径
    location / {
        root /home/temp/mdplus;
        index index.html index.htm;
    }
}

5.重启及验证

openresty -s reload
# 或者 /usr/local/openresty/nginx/sbin/nginx -s reload

tail -f /usr/local/openresty/nginx/logs/access.log

然后发起请求，查看/usr/local/openresty/nginx/logs/access.log是否打印response body的内容。