1、硬件环境：
联想R430X 2U服务器
2、软件环境
centos6.2 2.6.32-220.el6.x86_64
nginx-1.0.10.tar.gz
3、所用配置文件关键部分
daemon off; #注意关闭daemon模式server
{
listen 8100;
server_name www.nginx.com 192.168.15.127;
index index.html index.htm;
root /data0/htdocs/www;
location /ok{
load_status on;
}
}
4、nginx模块目录
cd /home/xuekun/nginx
mkdir ngx_module_load
5、编辑nginx模块的编译相关文件(config)
[root@centos6 nginx]# cat ngx_module_load/config
ngx_addon_name=ngx_module_load
HTTP_MODULES="$HTTP_MODULES ngx_module_load"
NGX_ADDON_SRCS="$NGX_ADDON_SRCS $ngx_addon_dir/ngx_module_load.c"
CORE_LIBS="$CORE_LIBS "
6、模块源码文件
#include
#include
#include
#include
static char *ngx_http_set_status(ngx_conf_t *cf, ngx_command_t *cmd,
void *conf);
static ngx_int_t ngx_load_average(ngx_int_t aload[], ngx_int_t nelem);
static ngx_command_t ngx_load_commands[] = {
{ ngx_string("load_status"),
NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_FLAG,
ngx_http_set_status,
0,
0,
NULL },
ngx_null_command
};
static ngx_http_module_t ngx_load_module_ctx = {
NULL, /* preconfiguration */
NULL, /* postconfiguration */
NULL, /* create main configuration */
NULL, /* init main configuration */
NULL, /* create server configuration */
NULL, /* merge server configuration */
NULL, /* create location configuration */
NULL /* merge location configuration */
};
ngx_module_t ngx_module_load = {
NGX_MODULE_V1,
&ngx_load_module_ctx, /* module context */
ngx_load_commands, /* module directives */
NGX_HTTP_MODULE, /* module type */
NULL, /* init master */
NULL, /* init module */
NULL, /* init process */
NULL, /* init thread */
NULL, /* exit thread */
NULL, /* exit process */
NULL, /* exit master */
NGX_MODULE_V1_PADDING
};
/*获取系统负载*/
static ngx_int_t ngx_load_average(ngx_int_t aload[], ngx_int_t nelem)
{
ngx_int_t i;
double loadavg[3];
getloadavg(loadavg, nelem);
for (i = 0; i
aload[i] = loadavg[i] * 1000;
}
return NGX_OK;
}
static ngx_int_t ngx_load_handler(ngx_http_request_t *r)
{
size_t size;
ngx_int_t rc;
ngx_buf_t *b;
ngx_chain_t out;
/*load value*/
ngx_int_t load;
if (r->method != NGX_HTTP_GET && r->method != NGX_HTTP_HEAD) {
return NGX_HTTP_NOT_ALLOWED;
}
rc = ngx_http_discard_request_body(r);
if (rc != NGX_OK) {
return rc;
}
ngx_str_set(&r->headers_out.content_type, "text/plain");
/*get loadavg*/
ngx_load_average(&load, 1);
if (r->method == NGX_HTTP_HEAD) {
r->headers_out.status = NGX_HTTP_OK;
rc = ngx_http_send_header(r);
if (rc == NGX_ERROR || rc > NGX_OK || r->header_only) {
return rc;
}
}
size = sizeof("Current loadavg: \n") + NGX_ATOMIC_T_LEN;
b = ngx_create_temp_buf(r->pool, size);
if (b == NULL) {
return NGX_HTTP_INTERNAL_SERVER_ERROR;
}
out.buf = b;
out.next = NULL;
b->last = ngx_sprintf(b->last, "Current loadavg:%1.3f\n", load * 1.0 / 1000);
r->headers_out.status = NGX_HTTP_OK;
r->headers_out.content_length_n = b->last - b->pos;
b->last_buf = 1;
rc = ngx_http_send_header(r);
if (rc == NGX_ERROR || rc > NGX_OK || r->header_only) {
return rc;
}
return ngx_http_output_filter(r, &out);
}
static char *ngx_http_set_status(ngx_conf_t *cf, ngx_command_t *cmd, void *conf)
{
ngx_http_core_loc_conf_t *clcf;
clcf = ngx_http_conf_get_module_loc_conf(cf, ngx_http_core_module);
clcf->handler = ngx_load_handler;
return NGX_CONF_OK;
}
7、configure，make
cd nginx-1.0.10
./configure --add-module=/home/xuekun/ngx_module_load/
8
、运行
nginx./objs/nginx -c /home/xuekun/cstudy/nginx/nginx-1.0.10/conf/nginx.conf
9、通过浏览器查看效果
