手把手教你开发Nginx模块

1、手把手教你开发Nginx模块前面的哪些话关于Nginx模块开发的博客资料，网上很多，很多。但是，每篇博客都只提要点，无法step by step照着做，对于初次接触Nginx开发的同学，只能像只盲目的蚂蚁瞎燥急！该篇文章没有太多技术深度，只是一步一步说明白Nginx模块的开发过程。开发环境搭建工欲善其事，必先利其器。个人推荐Eclipse CDT 作为IDE，原因很简单，代码提示与补全功能很全，完胜Codeblock这类.相信与否，试过就知道。在ubuntu下搭建开发环境：安装GCC编译器apt-get install build-essential安装pcre/openssl/zlib开发库

2、apt-get install libpcre3-devapt-get install libssl-devapt-get install libzip-dev必需安装nginx核心模块依赖的pcre,openssl,zilib开发库安装JRE/Eclipse CDTapt-get install openjdk-8-jrewget http:/ftp.yz.yamagata-u.ac.jp/pub/eclipse/technology/epp/downloads/release/neon/R/eclipse-cpp-neon-R-linux-gtk-x86_64.tar.gz & tzr -

3、xzvf eclipse-cpp-neon-R-linux-gtk-x86_64.tar.gz下载nginx源码wget /download/nginx-1.10.1.tar.gz & tar -xzvf nginx-1.10.1.tar.gz配置CDT Build Environment添加变量，值Nginx src下各模块路径，用冒号分隔，例如：/root/Workspace/nginx-1.10.1/src/core:/root/Workspace/nginx-1.10.1/src/event:/root/Workspace/nginx-1.10.1/src

4、/http:/root/Workspace/nginx-1.10.1/src/mail:/root/Workspace/nginx-1.10.1/src/stream:/root/Workspace/nginx-1.10.1/src/os/unix 添加环境变量，创建C项目时自动作为-I选项imageimageNginx模块编译流程Nginx使用configure脚本分析环境，自动生成objs结果。哪么configure如何编译第三方模块？答案是-add-module指定第三方模块目录，并将目录存为$ngx_addon_dir环境变量。执行$ngx_addon_dir/config脚本，读取模

5、块配置。在config中的环境变量分为2种：小写的本地环境变量，大写的全局环境变量。例如：ngx_addon_name=ngx_http_mytest_moduleHTTP_MODULES=$HTTP_MODULES ngx_http_mytest_module NGX_ADDON_SRCS=$NGX_ADDON_SRCS $ngx_addon_dir/ngx_http_mytest_moudle.cCORE_LIBS=$CORE_LIBS -lpcreHTTP_MODULES中的ngx_http_mytest_module就是NGX_ADDON_SRCS中源码(如果有多个，都要写上)ngx_

6、http_mytest_module.c中定义的ngx_module_t类型的全局变量。可见，第三方模块的入口点就是ngx_module_t类型全局变量，该变量又关联ngx_http_module_t类型static变量，与ngx_command_t类型static数组。在ngx_http_module_t中定义上下文配置nginx.conf解析的回调方法。在ngx_command_t中定义配置项处理的set回调方法。Nginx的全部操作都是异步的。在上述的方法中根据需要又会使用其他handler方法。以上可以看成Nginx第三方模块的起式。Upstream例子源码configngx_addo

7、n_name=ngx_http_mytest_moduleHTTP_MODULES=$HTTP_MODULES ngx_http_mytest_moduleNGX_ADDON_SRCS=$NGX_ADDON_SRCS $ngx_addon_dir/ngx_http_mytest_module.c源代码#include #include #include #include typedef struct ngx_http_upstream_conf_t upstream; mytest_conf_t;typedef struct ngx_http_status_t status; ngx_str_

8、t backendServer; mytest_ctx_t;static void *mytest_create_loc_conf(ngx_conf_t *cf);static char *mytest_merge_loc_conf(ngx_conf_t *cf, void *parent, void *child);static ngx_int_t mytest_upstream_create_request(ngx_http_request_t *r);static ngx_int_t mytest_upstream_process_status_line(ngx_http_request

9、_t *r);static ngx_int_t mytest_upstream_process_header(ngx_http_request_t *r);static void mytest_upstream_finalize_request(ngx_http_request_t *r, ngx_int_t rc);static ngx_int_t mytest_handler(ngx_http_request_t *r);static char *mytest(ngx_conf_t *cf, ngx_command_t *cmd, void *conf);static ngx_http_m

10、odule_t mytest_ctx = NULL, NULL, NULL, NULL, NULL, NULL, mytest_create_loc_conf, mytest_merge_loc_conf;static ngx_command_t mytest_commands = ngx_string(mytest), NGX_HTTP_MAIN_CONF | NGX_HTTP_SRV_CONF | NGX_HTTP_LOC_CONF | NGX_HTTP_LMT_CONF | NGX_CONF_NOARGS, mytest, NGX_HTTP_LOC_CONF_OFFSET, 0, NUL

11、L , ngx_null_command;ngx_module_t ngx_http_mytest_module = NGX_MODULE_V1, &mytest_ctx, mytest_commands, NGX_HTTP_MODULE, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NGX_MODULE_V1_PADDING;static ngx_str_t mytest_upstream_hide_headers = ngx_string(Date), ngx_string(Server), ngx_string(X-Pad), ngx_string

12、(X-Accel-Expires), ngx_string(X-Accel-Redirect), ngx_string(X-Accel-Limit-Rate), ngx_string(X-Accel-Buffering), ngx_string(X-Accel-Charset), ngx_null_string;static void *mytest_create_loc_conf(ngx_conf_t *cf) mytest_conf_t *mycf; mycf = (mytest_conf_t *)ngx_pcalloc(cf-pool, sizeof(mytest_conf_t); if

13、(mycf = NULL) return NULL; mycf-upstream.connect_timeout = 60000; mycf-upstream.send_timeout = 60000; mycf-upstream.read_timeout = 60000; mycf-upstream.store_access = 0600; mycf-upstream.buffering = 0; mycf-upstream.bufs.num = 8; mycf-upstream.bufs.size = ngx_pagesize; mycf-upstream.buffer_size = ng

14、x_pagesize; mycf-upstream.busy_buffers_size = 2 * ngx_pagesize; mycf-upstream.temp_file_write_size = 2 * ngx_pagesize; mycf-upstream.max_temp_file_size = 1024 * 1024 *1024; mycf-upstream.hide_headers = NGX_CONF_UNSET_PTR; mycf-upstream.pass_headers = NGX_CONF_UNSET_PTR; return mycf;static char *myte

15、st_merge_loc_conf(ngx_conf_t *cf, void *parent, void *child) mytest_conf_t *prev = (mytest_conf_t *)parent; mytest_conf_t *conf = (mytest_conf_t *)child; ngx_hash_init_t hash; hash.max_size = 100; hash.bucket_size = 1024; = proxy_headers_hash; if(ngx_http_upstream_hide_headers_hash(cf,&con

16、f-upstream, &prev-upstream,mytest_upstream_hide_headers,&hash)!=NGX_OK) return NGX_CONF_ERROR; return NGX_CONF_OK;static ngx_int_t mytest_upstream_create_request(ngx_http_request_t *r) static ngx_str_t backendQueryLine = ngx_string(GET /search?q=%V HTTP/1.1rnHost: .hkrnConnection: closernrn); ngx_in

17、t_t queryLineLen = backendQueryLine.len + r-args.len - 2; ngx_buf_t *b = ngx_create_temp_buf(r-pool, queryLineLen); if(b = NULL) return NGX_ERROR; b-last = b-pos + queryLineLen; ngx_snprintf(b-pos, queryLineLen, (char *)backendQueryLine.data, &r-args); r-upstream-request_bufs = ngx_alloc_chain_link(

18、r-pool); if(r-upstream-request_bufs = NULL) return NGX_ERROR; r-upstream-request_bufs-buf = b; r-upstream-request_bufs-next = NULL; r-upstream-request_sent = 0; r-upstream-header_sent = 0; r-header_hash = 1; return NGX_OK;static ngx_int_t mytest_upstream_process_status_line(ngx_http_request_t *r) si

19、ze_t len; ngx_int_t rc; ngx_http_upstream_t *u; mytest_ctx_t *ctx = ngx_http_get_module_ctx(r, ngx_http_mytest_module); if(ctx = NULL) return NGX_ERROR; u = r-upstream; rc = ngx_http_parse_status_line(r, &u-buffer, &ctx-status); if(rc = NGX_AGAIN) return rc; if(rc = NGX_ERROR) ngx_log_error(NGX_LOG_

20、ERR, r-connection-log, 0, upstream sent to valid HTTP/1.0 header); r-http_version = NGX_HTTP_VERSION_9; u-state-status = NGX_HTTP_OK; return NGX_OK; if(u-state) u-state-status = ctx-status.code; u-headers_in.status_n = ctx-status.code; len = ctx-status.end - ctx-status.start; u-headers_in.status_lin

21、e.len = len; u-headers_in.status_line.data = ngx_pcalloc(r-pool, len); if(u-headers_in.status_line.data = NULL) return NGX_ERROR; ngx_memcpy(u-headers_in.status_line.data, ctx-status.start, len); u-process_header = mytest_upstream_process_header; return mytest_upstream_process_header(r);static ngx_i

22、nt_t mytest_upstream_process_header(ngx_http_request_t *r) ngx_int_t rc; ngx_table_elt_t *h; ngx_http_upstream_header_t *hh; ngx_http_upstream_main_conf_t *umcf; umcf = ngx_http_get_module_main_conf(r, ngx_http_upstream_module); for(;) rc = ngx_http_parse_header_line(r, &r-upstream-buffer, 1); if(rc

23、 = NGX_OK) h = ngx_list_push(&r-upstream-headers_in.headers); if(h = NULL) return NGX_ERROR; h-hash = r-header_hash; h-key.len = r-header_name_end - r-header_name_start; h-value.len = r-header_end - r-header_start; h-key.data = ngx_pcalloc(r-pool, h-key.len + 1 + h-value.len + 1 + h-key.len); if(h-k

24、ey.data = NULL) return NGX_ERROR; h-value.data = h-key.data + h-key.len + 1; h-lowcase_key = h-key.data + h-key.len + 1 + h-value.len + 1; ngx_memcpy(h-key.data, r-header_name_start, h-key.len); h-key.datah-key.len=0; ngx_memcpy(h-value.data, r-header_start, h-value.len); h-value.datah-value.len = 0

25、; if(h-key.len = r-lowcase_index) ngx_memcpy(h-lowcase_key, r-lowcase_header, h-key.len); else ngx_strlow(h-lowcase_key, h-key.data, h-key.len); hh = ngx_hash_find(&umcf-headers_in_hash, h-hash, h-lowcase_key, h-key.len); if(hh & hh-handler(r, h, hh-offset)!=NGX_OK) return NGX_ERROR; continue; if(rc

26、 = NGX_HTTP_PARSE_HEADER_DONE) if(r-upstream-headers_in.server = NULL) h = ngx_list_push(&r-upstream-headers_in.headers); if(h = NULL) return NGX_ERROR; h-hash = ngx_hash(ngx_hash(ngx_hash(ngx_hash(ngx_hash(s, e), r), v), e), r); ngx_str_set(&h-key, Server); ngx_str_null(&h-value); h-lowcase_key = (

27、u_char *)server; if(r-upstream-headers_in.date = NULL) h = ngx_list_push(&r-upstream-headers_in.headers); if(h = NULL) return NGX_ERROR; h-hash = ngx_hash(ngx_hash(ngx_hash(d, a), t), e); ngx_str_set(&h-key, Date); ngx_str_null(&h-value); h-lowcase_key = (u_char *)date; return NGX_OK; if(rc = NGX_AG

28、AIN) return NGX_AGAIN; ngx_log_error(NGX_LOG_ERR, r-connection-log, 0, upstream sent invalid header); return NGX_HTTP_UPSTREAM_FT_INVALID_HEADER; static void mytest_upstream_finalize_request(ngx_http_request_t *r, ngx_int_t rc) ngx_log_error(NGX_LOG_DEBUG, r-connection-log, 0, mytest_upstream_finali

29、ze_request);static char *mytest(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 = mytest_handler; return NGX_CONF_OK;static ngx_int_t mytest_handler(ngx_http_request_t *r) mytest_ctx_t *my

30、ctx = ngx_http_get_module_ctx(r, ngx_http_mytest_module); if(myctx = NULL) myctx = ngx_pcalloc(r-pool, sizeof(mytest_ctx_t); if(myctx = NULL) return NGX_ERROR; ngx_http_set_ctx(r, myctx, ngx_http_mytest_module); if(ngx_http_upstream_create(r)!=NGX_OK) ngx_log_error(NGX_LOG_ERR, r-connection-log, 0,

31、ngx_http_upstream_create() failed); return NGX_ERROR; mytest_conf_t *mycf = (mytest_conf_t *)ngx_http_get_module_loc_conf(r, ngx_http_mytest_module); ngx_http_upstream_t *u = r-upstream; u-conf = &mycf-upstream; u-buffering = mycf-upstream.buffering; u-resolved = (ngx_http_upstream_resolved_t *) ngx

32、_pcalloc(r-pool, sizeof(ngx_http_upstream_resolved_t); if(u-resolved = NULL) ngx_log_error(NGX_LOG_ERR, r-connection-log, 0, ngx_pcalloc resolved error. %s, strerror(errno); return NGX_ERROR; static struct sockaddr_in backendSockAddr; struct hostent *pHost = gethostbyname(char *).hk); if(pHost = NUL

33、L) ngx_log_error(NGX_LOG_ERR, r-connection-log, 0, gethostbyname fail. %s, strerror(errno); return NGX_ERROR; backendSockAddr.sin_family = AF_INET; backendSockAddr.sin_port = htons(in_port_t)80); char *pDmsIP = inet_ntoa(*(struct in_addr *)(pHost-h_addr_list0); backendSockAddr.sin_addr.s_addr = inet

34、_addr(pDmsIP); myctx-backendServer.data = (u_char *)pDmsIP; myctx-backendServer.len = strlen(pDmsIP); u-resolved-sockaddr = (struct sockaddr *)&backendSockAddr; u-resolved-port = htons(in_port_t)80); u-resolved-socklen = sizeof(struct sockaddr_in); u-resolved-naddrs = 1; u-create_request = mytest_up

35、stream_create_request; u-process_header = mytest_upstream_process_status_line; u-finalize_request = mytest_upstream_finalize_request; r-main-count+; ngx_http_upstream_init(r); return NGX_DONE;注意：Nginx深入解析的demo少了这句：“u-resolved-port = htons(in_port_t)80);”，否则报错“2016/09/09 11:24:18 error 28352#0: *1 no

36、 port in upstream , client: , server: localhost, request: GET /mytest?q=test HTTP/1.1, host: localhost”编译脚本./configure -prefix=/usr/local/nginx -add-module=/root/Workspace/nginx-modules/ngx_http_mytest_module -with-debugsudo makesudo make install安装后即可到/usr/local/nginx下配置nginx.conf进行测试。Subre

37、quest例子源码configngx_addon_name=ngx_http_mytest_moduleHTTP_MODULES=$HTTP_MODULES ngx_http_mytest_moduleNGX_ADDON_SRCS=$NGX_ADDON_SRCS $ngx_addon_dir/ngx_http_mytest_module.c源代码#include #include #include typedef struct ngx_str_t stock6; mytest_ctx_t;static ngx_int_t mytest_subrequest_post_handler(ngx_h

38、ttp_request_t *r, void *data, ngx_int_t rc);static void mytest_post_handler(ngx_http_request_t *r);static ngx_int_t mytest_handler(ngx_http_request_t *r);static char *mytest(ngx_conf_t *cf, ngx_command_t *cmd, void *conf);static ngx_http_module_t mytest_conf = NULL, NULL, NULL, NULL, NULL, NULL, NUL

39、L, NULL;static ngx_command_t mytest_commands = ngx_string(mytest), NGX_HTTP_MAIN_CONF | NGX_HTTP_SRV_CONF | NGX_HTTP_LOC_CONF | NGX_CONF_NOARGS, mytest, NGX_HTTP_LOC_CONF_OFFSET, 0, NULL , ngx_null_command;ngx_module_t ngx_http_mytest_module = NGX_MODULE_V1, &mytest_conf, mytest_commands, NGX_HTTP_M

40、ODULE, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NGX_MODULE_V1_PADDING;static ngx_int_t mytest_subrequest_post_handler(ngx_http_request_t *r, void *data, ngx_int_t rc) ngx_http_request_t *pr = r-parent; mytest_ctx_t *myctx = ngx_http_get_module_ctx(pr, ngx_http_mytest_module); pr-headers_out.status

41、= r-headers_out.status; if (r-headers_out.status = NGX_HTTP_OK) int flag = 0; ngx_buf_t *pRecvBuf = &r-upstream-buffer; for (; pRecvBuf-pos != pRecvBuf-last; pRecvBuf-pos+) if (*pRecvBuf-pos = , | *pRecvBuf-pos = ) if (flag 0) myctx-stockflag - 1.len = pRecvBuf-pos - myctx-stockflag - 1.data; flag+;

42、 myctx-stockflag - 1.data = pRecvBuf-pos + 1; if (flag 6) break; pr-write_event_handler = mytest_post_handler; return NGX_OK;static void mytest_post_handler(ngx_http_request_t *r) if(r-headers_out.status != NGX_HTTP_OK) ngx_http_finalize_request(r,r-headers_out.status); return; mytest_ctx_t *myctx =

43、 ngx_http_get_module_ctx(r,ngx_http_mytest_module); ngx_str_t output_format = ngx_string(stock%V,Today current price:%V, volumn:%V); int bodylen = output_format.len + myctx-stock0.len + myctx-stock1.len + myctx-stock4.len - 6; r-headers_out.content_length_n = bodylen; ngx_buf_t *b = ngx_create_temp_

44、buf(r-pool, bodylen); ngx_snprintf(b-pos,bodylen,(char *)output_format.data, &myctx-stock0, &myctx-stock1, &myctx-stock4); b-last = b-pos + bodylen; b-last_buf = 1; ngx_chain_t out; out.buf = b; out.next = NULL; static ngx_str_t type = ngx_string(text/plain; charset=GBK); r-headers_out.content_type = type; r-hea