重寫查詢字符串路徑參數

Question

我nginx的以下配置承載我的形象服務：

upstream thumbor { 
     server localhost:8888; 
    } 

    server { 
     listen  80; 
     server_name my.imageserver.com; 
     client_max_body_size 10M; 
     rewrite_log on; 
     location ~ /images { 
      if ($arg_width="10"){ 
       rewrite ^/images(/.*)$ /unsafe/$1 last; 
      } 
      rewrite ^/images(/.*)$ /unsafe/$1 last; 
     } 
     location ~ /unsafe { 
      proxy_set_header X-Real-IP $remote_addr; 
      proxy_set_header HOST $http_host; 
      proxy_set_header X-NginX-Proxy true; 

      proxy_pass http://thumbor; 
      proxy_redirect off; 
     } 

     location = /favicon.ico { 
      return 204; 
      access_log  off; 
      log_not_found off; 
     } 
    } 

我試圖改寫以下網址：從

http://my.imageserver.com/images/Jenesis/EmbeddedImage/image/jpeg/jpeg/9f5d124d-068d-43a4-92c0-1c044584c54a.jpeg

至

http://my.imageserver.com/unsafe/Jenesis/EmbeddedImage/image/jpeg/jpeg/9f5d124d-068d-43a4-92c0-1c044584c54a.jpeg

這是很容易的，問題開始時我想允許查詢字符串應該去URL的路徑，像這樣：

從

http://my.imageserver.com/images/Jenesis/EmbeddedImage/image/jpeg/jpeg/9f5d124d-068d-43a4-92c0-1c044584c54a.jpeg?width=150&height=200&mode=smart

至

http://my.imageserver.com/unsafe/150x200/smart/Jenesis/EmbeddedImage/image/jpeg/jpeg/9f5d124d-068d-43a4-92c0-1c044584c54a.jpeg

此外它會更好，如果查詢字符串的順序無關緊要。

我試過使用： $ arg_width但它似乎沒有工作。

在Ubuntu上使用nginx 1.6.1。

幫助將非常感激。

Answer 1

處理查詢參數總是很難（對於Apache也是如此）。

但是當你做你的榜樣：

location ~ /images { 
    if ($arg_width="10"){ 
     rewrite ^/images(/.*)$ /unsafe/$1 last; 
    } 
    rewrite ^/images(/.*)$ /unsafe/$1 last; 
} 

我沒有看到2次重寫任何區別......所以這就是爲什麼，也許它不能正常工作。

反正你也許可以嘗試類似的東西（基於this thread）：

location ^~ /images { 
    # get there only if we have a query string 
    if ($is_args) { 
     set $width ""; 
     set $height ""; 
     if ($args ~* "(?:^|&)width=([^&]+)") { 
      set $width $1; 
     } 
     if ($args ~* "(?:^|&)height=([^&]+)") { 
      set $height $1; 
     } 

     # string concatenation using sort of bash syntax 
     set $dim "${width}x${height}"; 
     # maybe we should add a control here on $dim !='x'... 

     # the ? here prevent query string from being appended 
     rewrite ^/images(/.*)$ /unsafe/$dim/$1? last; 
    } 
    rewrite ^/images(/.*)$ /unsafe/$1 last; 
} 
location ~ /unsafe { 
    (...) 

Answer 2

可以使用arg_name參數，你可以擺脫location塊：

rewrite ^/images/(.*)$ /unsafe/$1; 
# WARNING: Here we suppose that when we have a "mode" parameter, we have 
# width and height paremeters too 
if ($arg_mode) { 
    rewrite ^/unsafe/(.*)$ /images/unsafe/smart/$arg_mode/${arg_width}x${arg_height}/$1 last; 
} 

Answer 3

您需要作爲可以評估輸入並構建重寫URL的腳本選項。我使用第三方Nginx Lua Module這樣的邏輯。

在您的機器上安裝Lua或最好是LuaJit之後，您需要將模塊編譯爲Nginx。

或者，您可以安裝Openresty這是Nginx捆綁了幾個模塊，將Nginx完全轉換爲完整的Web應用程序服務器。在安裝過程中，Openresty將負責處理Lua/LuaJit依賴項。

如果你有這樣的地方，這應該爲你做的工作：

upstream thumbor { 
    server localhost:8888; 
} 
server { 
    [...] 
    location ~ ^/images { 
     rewrite_by_lua ' 
      -- Use local variables to limit their scope to this location block 
      local i, j, key, val, args, dimension, modetype, tempheight, replacement 

      -- We only go ahead if there are request arguments to start with 
      if ngx.var.is_args then 
       -- Get the request arguments 
       -- These are loaded into a Lua table of the form, { a = 1, b = 2, c = 3 } 
       args = ngx.req.get_uri_args() 
       -- Loop through the args table and build our replacement string 
       for key, val in pairs(args) do 
        if key == "width" then 
         if tempheight then 
          dimension = val .. "x" .. tempheight 
         else 
          dimension = val 
         end 
        elseif key == "height" then 
         if dimension then 
          dimension = dimension .. "x" .. val 
         else 
          tempheight = val 
         end 
        elseif key == "mode" then 
         modetype = val 
        end 
       end 

       -- Construct the replacement string. 
       replacement = "/unsafe/" .. dimension .. "/" .. modetype .. "/" 

       -- Replace "/images/" in the request url with the replacement string. 
       local newuri, n, err = ngx.re.sub(ngx.unescape_uri(ngx.var.request_uri), "/images/", replacement, "io") 

       -- If there is a new string, then redirect to the new URL 
       if newuri then 
        return ngx.redirect(newuri, 301) 
       end 
      end 
     '; 
    } 
    location ~ /unsafe { 
     [...] 
     proxy_pass http://thumbor; 
    } 
    [...] 
}