学步园

以前一直写的都是nginx的handler模块，包括线上服务器都是handler模块，还没有真正写过filter模块，这里就张贴一个filter模块的骨架，方便自己以后查阅。这个入门级的filter只是简单的在响应body尾添加上字符串“Nginx”。

#include <ngx_config.h><br /> #include <ngx_core.h><br /> #include <ngx_http.h><br /> static ngx_int_t<br /> ngx_http_test_filter_init(ngx_conf_t *cf);<br /> static ngx_http_module_t ngx_http_test_filter_module_ctx = {<br /> NULL, /* preconfiguration */<br /> ngx_http_test_filter_init, /* postconfiguration */<br /> NULL, /* create main configuration */<br /> NULL, /* init main configuration */<br /> NULL, /* create server configuration */<br /> NULL, /* merge server configuration */<br /> NULL, /* create location configuration */<br /> NULL /* merge location configuration */<br /> };<br /> ngx_module_t ngx_http_test_filter_module = {<br /> NGX_MODULE_V1,<br /> &ngx_http_test_filter_module_ctx, /* module context */<br /> NULL, /* module directives */<br /> NGX_HTTP_MODULE, /* module type */<br /> NULL, /* init master */<br /> NULL, /* init module */<br /> NULL, /* init process */<br /> NULL, /* init thread */<br /> NULL, /* exit thread */<br /> NULL, /* exit process */<br /> NULL, /* exit master */<br /> NGX_MODULE_V1_PADDING<br /> };<br /> static ngx_http_output_header_filter_pt ngx_http_next_header_filter;<br /> static ngx_http_output_body_filter_pt ngx_http_next_body_filter;<br /> static ngx_int_t<br /> ngx_http_test_header_filter(ngx_http_request_t *r)<br /> {<br /> if (r != r->main) {<br /> return ngx_http_next_header_filter(r);<br /> }<br /> r->headers_out.content_length_n += sizeof("Nginx") - 1;<br /> return ngx_http_next_header_filter(r);<br /> }<br /> static ngx_int_t<br /> ngx_http_test_body_filter(ngx_http_request_t *r, ngx_chain_t *in)<br /> {<br /> if (r != r->main) {<br /> return ngx_http_next_body_filter(r, in);<br /> }<br /> ngx_chain_t *chain_link;<br /> int chain_contains_last_buffer = 0;<br /> for ( chain_link = in; chain_link != NULL; chain_link = chain_link->next ) {<br /> if (chain_link->buf->last_buf) {<br /> chain_contains_last_buffer = 1;<br /> break;<br /> }<br /> }<br /> if (!chain_contains_last_buffer)<br /> return ngx_http_next_body_filter(r, in);<br /> ngx_buf_t *b;<br /> b = ngx_calloc_buf(r->pool);<br /> if (b == NULL) {<br /> return NGX_ERROR;<br /> }<br /> b->pos = (u_char *) "Nginx";<br /> b->last = b->pos + sizeof("Nginx") - 1;<br /> b->memory = 1;<br /> b->last_buf = 1;<br /> ngx_chain_t *added_link;<br /> added_link = ngx_alloc_chain_link(r->pool);<br /> if (added_link == NULL)<br /> return NGX_ERROR;<br /> added_link->buf = b;<br /> added_link->next = NULL;<br /> chain_link->next = added_link;<br /> chain_link->buf->last_buf = 0;<br /> added_link->buf->last_buf = 1;<br /> return ngx_http_next_body_filter(r, in);<br /> }<br /> static ngx_int_t<br /> ngx_http_test_filter_init(ngx_conf_t *cf)<br /> {<br /> ngx_http_next_header_filter = ngx_http_top_header_filter;<br /> ngx_http_top_header_filter = ngx_http_test_header_filter;<br /> ngx_http_next_body_filter = ngx_http_top_body_filter;<br /> ngx_http_top_body_filter = ngx_http_test_body_filter;<br /> return NGX_OK;<br /> }<br />  

config内容：

ngx_addon_name=ngx_http_test_filter_module<br /> HTTP_AUX_FILTER_MODULES="$HTTP_AUX_FILTER_MODULES ngx_http_test_filter_module"<br /> NGX_ADDON_SRCS="$NGX_ADDON_SRCS $ngx_addon_dir/ngx_http_test_filter_module.c"