trim support variable value (on/off). (https://github.com/alibaba/tengine/issues/368)

docs/modules/ngx_http_trim_filter_module.md

@@ -23,6 +23,14 @@ HTML with a state machine.
      
 Enable or disable trim module for pure HTML.  
 This module will retain some contents unchanged, in case that they are enclosed by the tag `pre`,`textarea`,`script` and `style`,as well as IE/SSI/ESI comments.  
+Parameter value can contain variables.  
+Example:  
+
+    set $flag "off";
+    if ($condition) {
+        set $flag "on";
+    }
+    trim $flag;
 <br/>
 
 
@@ -33,6 +41,7 @@ This module will retain some contents unchanged, in case that they are enclosed
 **Context:** `http, server, location` 
      
 Enable or disable trim module for inline javascript.  
+Parameter value can contain variables too.  
 <br/>
 
 
@@ -43,6 +52,7 @@ Enable or disable trim module for inline javascript.
 **Context:** `http, server, location` 
      
 Enable or disable trim module for inline css.  
+Parameter value can contain variables too.  
 <br/>
 
 
@@ -107,3 +117,52 @@ result:
     <script type="text/javascript">str.replace(/     /,"hello");</script>
     <style type="text/css">body{font-size:20px;line-height:150%;}</style>
 
+
+## Trim Rule
+
+### Html
+##### Whitespace
++ Remove '\r'.
++ Replace '\t' with space.
++ Replace multiple spaces with a single space.
++ Replace multiple '\n' with a single '\n'.
++ Replace multiple '\n' and '\t' in tag with a single space.
++ Do not trim quoted strings in tag.
++ Do not trim the contents enclosed by the tag `pre`,`textarea`,`script` and `style`.
+
+##### Comment
++ Remove html comment(`<!-- -->`).
++ Do not trim IE/SSI/ESI comments.  
+  IE comment: `<!--[if  <![endif]-->`  
+  SSI comment: `<!--#  -->`  
+  ESI comment: `<!--esi  -->`  
+
+
+### Javascript
+Contents enclosed by `<script type="text/javascript">` or `<script>` will be identified as javascript.
+
+##### Whitespace
++ Remove '\r'.
++ Remove '\t','\n' and space that behind '(',',','=',':','[','!','&','|','?',';','>','~','*','{'.
++ Replace multiple spaces with a single space.
++ Do not trim quoted strings and regular expression literals.
+
+##### Comment
++ Remove single comment. `//`
++ Remove multi comment. `/*  */`
+
+
+### Css
+Contents enclosed by `<style type="text/css">` or `<style>` will be identified as css.
+
+##### Whiltespace
++ Remove '\r'.
++ Remove '\t','\n' and space that around ';','>','{','}',':',','.
++ Replace multiple '\n' and spaces with a single space.
++ Do not trim quoted strings.
+
+##### Comment
++ Remove css comment(`/* */`).
++ Do not remove child seletor and IE5 /Mac hack comments.  
+  Child seletor hack: `html>/**/body p{color:blue}`  
+  IE5 /Mac hack: `/*\*/.selector{color:khaki}/**/`  

docs/modules/ngx_http_trim_filter_module_cn.md

@@ -22,7 +22,15 @@
 **上下文:** `http, server, location` 
      
 使模块有效（失效），删除 html 的注释以及重复的空白符（\n，\r，\t，' '）。   
-例外：对于 `pre`，`textarea`，`script`，`style` 和 ie/ssi/esi注释 等标签内的内容不作删除操作。   
+例外：对于 `pre`，`textarea`，`script`，`style` 和 ie/ssi/esi注释 等标签内的内容不作删除操作。  
+参数值可以包含变量。  
+例如：
+
+    set $flag "off";
+    if ($condition) {
+        set $flag "on";
+    }
+    trim $flag;
 <br/>
 
 **trim_js** `on` | `off`
@@ -32,7 +40,8 @@
 **上下文:** `http, server, location` 
      
 使模块有效（失效），删除 html 内嵌 javascript 的注释以及重复的空白符（\n，\r，\t，' '）。   
-例外：对于非javascript代码的 `script` 标签内容不作删除操作。   
+例外：对于非javascript代码的 `script` 标签内容不作删除操作。  
+参数值可以包含变量。 
 <br/>
 
 **trim_css** `on` | `off`
@@ -42,7 +51,8 @@
 **上下文:** `http, server, location` 
      
 使模块有效（失效），删除 html 内嵌 css 的注释以及重复的空白符（\n，\r，\t，' ')。   
-例外：对于非css代码的 `style` 标签内容不作删除操作。   
+例外：对于非css代码的 `style` 标签内容不作删除操作。  
+参数值可以包含变量。 
 <br/>
 
 **trim_types** `MIME types`

src/http/modules/ngx_http_trim_filter_module.c

@@ -23,11 +23,12 @@
 #define NGX_HTTP_TRIM_TAG_TEXTAREA       4
 
 typedef struct {
-    ngx_flag_t      trim_enable;
-    ngx_flag_t      js_enable;
-    ngx_flag_t      css_enable;
-    ngx_hash_t      types;
-    ngx_array_t    *types_keys;
+    ngx_hash_t                   types;
+    ngx_array_t                 *types_keys;
+
+    ngx_http_complex_value_t    *js;
+    ngx_http_complex_value_t    *css;
+    ngx_http_complex_value_t    *trim;
 } ngx_http_trim_loc_conf_t;
 
 
@@ -45,6 +46,9 @@ typedef struct {
     ngx_int_t       saved;
     ngx_int_t       count;
     ngx_uint_t      state;
+
+    unsigned        js_enable:1;
+    unsigned        css_enable:1;
 } ngx_http_trim_ctx_t;
 
 
@@ -167,24 +171,24 @@ static ngx_int_t ngx_http_trim_filter_init(ngx_conf_t *cf);
 static ngx_command_t  ngx_http_trim_commands[] = {
 
     { ngx_string("trim"),
-      NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_FLAG,
-      ngx_conf_set_flag_slot,
+      NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_TAKE1,
+      ngx_http_set_complex_value_slot,
       NGX_HTTP_LOC_CONF_OFFSET,
-      offsetof(ngx_http_trim_loc_conf_t, trim_enable),
+      offsetof(ngx_http_trim_loc_conf_t, trim),
       NULL },
 
     { ngx_string("trim_js"),
-      NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_FLAG,
-      ngx_conf_set_flag_slot,
+      NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_TAKE1,
+      ngx_http_set_complex_value_slot,
       NGX_HTTP_LOC_CONF_OFFSET,
-      offsetof(ngx_http_trim_loc_conf_t, js_enable),
+      offsetof(ngx_http_trim_loc_conf_t, js),
       NULL },
 
     { ngx_string("trim_css"),
-      NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_FLAG,
-      ngx_conf_set_flag_slot,
+      NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_TAKE1,
+      ngx_http_set_complex_value_slot,
       NGX_HTTP_LOC_CONF_OFFSET,
-      offsetof(ngx_http_trim_loc_conf_t, css_enable),
+      offsetof(ngx_http_trim_loc_conf_t, css),
       NULL },
 
     { ngx_string("trim_types"),
@@ -258,7 +262,7 @@ ngx_http_trim_header_filter(ngx_http_request_t *r)
 
     conf = ngx_http_get_module_loc_conf(r, ngx_http_trim_filter_module);
 
-    if (!conf->trim_enable
+    if (!conf->trim
         || r->headers_out.status != NGX_HTTP_OK
         || (r->method & NGX_HTTP_HEAD)
         || r->headers_out.content_length_n == 0
@@ -279,11 +283,45 @@ ngx_http_trim_header_filter(ngx_http_request_t *r)
         return ngx_http_next_header_filter(r);
     }
 
+    if (ngx_http_complex_value(r, conf->trim, &flag) != NGX_OK) {
+        return NGX_ERROR;
+    }
+
+    if (!(flag.len == sizeof("on") - 1
+          && ngx_strncmp(flag.data, "on", sizeof("on") - 1) == 0))
+    {
+        return ngx_http_next_header_filter(r);
+    }
+
     ctx = ngx_pcalloc(r->pool, sizeof(ngx_http_trim_ctx_t));
     if (ctx == NULL) {
         return NGX_ERROR;
     }
 
+    if (conf->js) {
+        if (ngx_http_complex_value(r, conf->js, &flag) != NGX_OK) {
+            return NGX_ERROR;
+        }
+
+        if (flag.len == sizeof("on") - 1
+            && ngx_strncmp(flag.data, "on", sizeof("on") - 1) == 0)
+        {
+            ctx->js_enable = 1;
+        }
+    }
+
+    if (conf->css) {
+        if (ngx_http_complex_value(r, conf->css, &flag) != NGX_OK) {
+            return NGX_ERROR;
+        }
+
+        if (flag.len == sizeof("on") - 1
+            && ngx_strncmp(flag.data, "on", sizeof("on") - 1) == 0)
+        {
+            ctx->css_enable = 1;
+        }
+    }
+
     ctx->prev = ' ';
 
     ngx_http_set_ctx(r, ctx, ngx_http_trim_filter_module);
@@ -551,7 +589,7 @@ ngx_http_trim_parse(ngx_http_request_t *r, ngx_buf_t *buf,
                     ctx->state = trim_state_tag_textarea_end;
 
                 } else if (ctx->tag == NGX_HTTP_TRIM_TAG_SCRIPT) {
-                    if (conf->js_enable
+                    if (ctx->js_enable
                         && ctx->looked == ngx_http_trim_script_js.len)
                     {
                         ctx->state = trim_state_tag_script_js_text;
@@ -561,7 +599,7 @@ ngx_http_trim_parse(ngx_http_request_t *r, ngx_buf_t *buf,
                     }
 
                 } else if (ctx->tag == NGX_HTTP_TRIM_TAG_STYLE) {
-                    if (conf->css_enable
+                    if (ctx->css_enable
                         && ctx->looked == ngx_http_trim_style_css.len)
                     {
                         ctx->state = trim_state_tag_style_css_text;
@@ -782,7 +820,7 @@ ngx_http_trim_parse(ngx_http_request_t *r, ngx_buf_t *buf,
             look = ngx_http_trim_script.data[ctx->looked++];    /* <script> */
             if (ch == look) {
                 if (ctx->looked == ngx_http_trim_script.len) {
-                    if (conf->js_enable) {
+                    if (ctx->js_enable) {
                         ctx->state = trim_state_tag_script_js_text;
 
                     } else {
@@ -1166,7 +1204,7 @@ ngx_http_trim_parse(ngx_http_request_t *r, ngx_buf_t *buf,
             look = ngx_http_trim_style.data[ctx->looked++];    /* <style> */
             if (ch == look) {
                 if (ctx->looked == ngx_http_trim_style.len) {
-                    if (conf->css_enable) {
+                    if (ctx->css_enable) {
                         ctx->state = trim_state_tag_style_css_text;
 
                     } else {
@@ -1796,7 +1834,7 @@ ngx_http_trim_parse(ngx_http_request_t *r, ngx_buf_t *buf,
                     ctx->state = trim_state_tag_textarea_end;
 
                 } else if (ctx->tag == NGX_HTTP_TRIM_TAG_SCRIPT) {
-                    if (conf->js_enable
+                    if (ctx->js_enable
                         && ctx->looked == ngx_http_trim_script_js.len)
                     {
                         ctx->state = trim_state_tag_script_js_text;
@@ -1806,7 +1844,7 @@ ngx_http_trim_parse(ngx_http_request_t *r, ngx_buf_t *buf,
                     }
 
                 } else if (ctx->tag == NGX_HTTP_TRIM_TAG_STYLE) {
-                    if (conf->css_enable
+                    if (ctx->css_enable
                         && ctx->looked == ngx_http_trim_style_css.len)
                     {
                         ctx->state = trim_state_tag_style_css_text;
@@ -1847,7 +1885,7 @@ ngx_http_trim_parse(ngx_http_request_t *r, ngx_buf_t *buf,
                 break;
             }
 
-            if (conf->js_enable && ctx->tag == NGX_HTTP_TRIM_TAG_SCRIPT) {
+            if (ctx->js_enable && ctx->tag == NGX_HTTP_TRIM_TAG_SCRIPT) {
                 if (ctx->looked != ngx_http_trim_script_js.len) {
                     look = ngx_http_trim_script_js.data[ctx->looked++];
                     if (ch != look) {
@@ -1856,7 +1894,7 @@ ngx_http_trim_parse(ngx_http_request_t *r, ngx_buf_t *buf,
                 }
             }
 
-            if (conf->css_enable && ctx->tag == NGX_HTTP_TRIM_TAG_STYLE) {
+            if (ctx->css_enable && ctx->tag == NGX_HTTP_TRIM_TAG_STYLE) {
                 if (ctx->looked != ngx_http_trim_style_css.len) {
                     look = ngx_http_trim_style_css.data[ctx->looked++];
                     if (ch != look) {
@@ -1876,7 +1914,7 @@ ngx_http_trim_parse(ngx_http_request_t *r, ngx_buf_t *buf,
                 break;
             }
 
-            if (conf->js_enable && ctx->tag == NGX_HTTP_TRIM_TAG_SCRIPT) {
+            if (ctx->js_enable && ctx->tag == NGX_HTTP_TRIM_TAG_SCRIPT) {
                 if (ctx->looked != ngx_http_trim_script_js.len) {
                     look = ngx_http_trim_script_js.data[ctx->looked++];
                     if (ch != look) {
@@ -1885,7 +1923,7 @@ ngx_http_trim_parse(ngx_http_request_t *r, ngx_buf_t *buf,
                 }
             }
 
-            if (conf->css_enable && ctx->tag == NGX_HTTP_TRIM_TAG_STYLE) {
+            if (ctx->css_enable && ctx->tag == NGX_HTTP_TRIM_TAG_STYLE) {
                 if (ctx->looked != ngx_http_trim_style_css.len) {
                     look = ngx_http_trim_style_css.data[ctx->looked++];
                     if (ch != look) {
@@ -1924,12 +1962,11 @@ ngx_http_trim_create_loc_conf(ngx_conf_t *cf)
      *
      *     conf->types = { NULL };
      *     conf->types_keys = NULL;
+     *     conf->trim = NULL;
+     *     conf->js = NULL;
+     *     conf->css = NULL;
      */
 
-    conf->trim_enable = NGX_CONF_UNSET;
-    conf->js_enable = NGX_CONF_UNSET;
-    conf->css_enable = NGX_CONF_UNSET;
-
     return conf;
 }
 
@@ -1940,10 +1977,6 @@ ngx_http_trim_merge_loc_conf(ngx_conf_t *cf, void *parent, void *child)
     ngx_http_trim_loc_conf_t *prev = parent;
     ngx_http_trim_loc_conf_t *conf = child;
 
-    ngx_conf_merge_value(conf->js_enable, prev->js_enable, 0);
-    ngx_conf_merge_value(conf->css_enable, prev->css_enable, 0);
-    ngx_conf_merge_value(conf->trim_enable, prev->trim_enable, 0);
-
     if (ngx_http_merge_types(cf, &conf->types_keys, &conf->types,
                              &prev->types_keys, &prev->types,
                              ngx_http_html_default_types)
@@ -1952,6 +1985,18 @@ ngx_http_trim_merge_loc_conf(ngx_conf_t *cf, void *parent, void *child)
         return NGX_CONF_ERROR;
     }
 
+    if (conf->trim == NULL) {
+        conf->trim = prev->trim;
+    }
+
+    if (conf->js == NULL) {
+        conf->js = prev->js;
+    }
+
+    if (conf->css == NULL) {
+        conf->css = prev->css;
+    }
+
     return NGX_CONF_OK;
 }
 

tests/test-nginx/cases/trim.t

@@ -738,3 +738,80 @@ h1 > strong {  color : red  ; }
     GET /t/trim.html
 --- response_body
 <style>body{font-size:20px;line-height:150%;}body{font-size:20px;line-height:150%;}body{font-size:20px;line-height:150%;}body{font-size:20px;line-height:150%;}h1>strong{color:red;}.skin-1388458850088 .nav .sm-item-list{border-bottom:2px solid #ee5e80;}.skin-1388458850088 .nav .search-wrap a.local,.skin-1388458850088 .nav .search-wrap a.local:hover{background:#ee5e80;}</style>
+
+
+=== TEST 27: variable value
+--- config
+    trim on;
+    trim_js on;
+    trim_css on;
+    set $trim "on";
+    if ($arg_a = 1 ) {
+        set $trim "off";
+    }
+    location /trim.html {trim off; }
+    location /t/ {
+        proxy_buffering off;
+        proxy_pass http://127.0.0.1:$TEST_NGINX_TRIM_PORT/;
+
+        trim_js $trim;
+        trim_css $trim;
+    }
+--- user_files
+>>> trim.html
+<!DOCTYPE html>
+<textarea  >
+   trim
+        module
+</textarea  >
+<!--remove all-->
+<!--[if IE]> trim module <![endif]-->
+<!--[if !IE ]>--> trim module  <!--<![endif]-->
+<!--# ssi-->
+<!--esi-->
+<pre    style  =
+    "color:   blue"  >Welcome    to    nginx!</pre  >
+<script type="text/javascript">
+/***  muitl comment
+                   ***/
+//// single comment
+str.replace(/     /,"hello");
+</script>
+<style   type="text/css"  >
+/*** css comment
+                 ! ***/
+body
+{
+  font-size:  20px ;
+  line-height: 150% ;
+}
+</style>
+--- request
+    GET /t/trim.html?a=1
+--- response_body
+<!DOCTYPE html>
+<textarea>
+   trim
+        module
+</textarea>
+<!--[if IE]> trim module <![endif]-->
+<!--[if !IE ]>--> trim module  <!--<![endif]-->
+<!--# ssi-->
+<!--esi-->
+<pre style="color:   blue">Welcome    to    nginx!</pre>
+<script type="text/javascript">
+/***  muitl comment
+                   ***/
+//// single comment
+str.replace(/     /,"hello");
+</script>
+<style type="text/css">
+/*** css comment
+                 ! ***/
+body
+{
+  font-size:  20px ;
+  line-height: 150% ;
+}
+</style>
+