The Tor Browser: dom/downloads/tests/serve_file.sjs@b8a032363ba2 (annotated)

dom/downloads/tests/serve_file.sjs@b8a032363ba2 (annotated)

dom/downloads/tests/serve_file.sjs

Thu, 22 Jan 2015 13:21:57 +0100

author: Michael Schloh von Bennewitz <michael@schloh.com>
date: Thu, 22 Jan 2015 13:21:57 +0100
branch: TOR_BUG_9701
changeset 15: b8a032363ba2
permissions: -rw-r--r--

Incorporate requested changes from Mozilla in review:
https://bugzilla.mozilla.org/show_bug.cgi?id=1123480#c6

 // Serves a file with a given mime type and size at an optionally given rate.
 function getQuery(request) {
   var query = {};
   request.queryString.split('&').forEach(function (val) {
     var [name, value] = val.split('=');
     query[name] = unescape(value);
   });
   return query;
 }
 function handleResponse() {
   // Is this a rate limited response?
   if (this.state.rate > 0) {
     // Calculate how many bytes we have left to send.
     var bytesToWrite = this.state.totalBytes - this.state.sentBytes;
     // Do we have any bytes left to send? If not we'll just fall thru and
     // cancel our repeating timer and finalize the response.
     if (bytesToWrite > 0) {
       // Figure out how many bytes to send, based on the rate limit.
       bytesToWrite =
         (bytesToWrite > this.state.rate) ? this.state.rate : bytesToWrite;
       for (let i = 0; i < bytesToWrite; i++) {
         try {
           this.response.bodyOutputStream.write("0", 1);
         } catch (e) {
           // Connection was closed by client.
           if (e == Components.results.NS_ERROR_NOT_AVAILABLE) {
             // There's no harm in calling this multiple times.
             this.response.finish();
             // It's possible that our timer wasn't cancelled in time
             // and we'll be called again.
             if (this.timer) {
               this.timer.cancel();
               this.timer = null;
             }
             return;
           }
         }
       }
       // Update the number of bytes we've sent to the client.
       this.state.sentBytes += bytesToWrite;
       // Wait until the next call to do anything else.
       return;
     }
   }
   else {
     // Not rate limited, write it all out.
     for (let i = 0; i < this.state.totalBytes; i++) {
       this.response.write("0");
     }
   }
   // Finalize the response.
   this.response.finish();
   // All done sending, go ahead and cancel our repeating timer.
   this.timer.cancel();
   // Clear the timer.
   this.timer = null;
 }
 function handleRequest(request, response) {
   var query = getQuery(request);
   // sending at a specific rate requires our response to be asynchronous so
   // we handle all requests asynchronously. See handleResponse().
   response.processAsync();
   // Default status when responding.
   var version = "1.1";
   var statusCode = 200;
   var description = "OK";
   // Default values for content type, size and rate.
   var contentType = "text/plain";
   var contentRange = null;
   var size = 1024;
   var rate = 0;
   // optional content type to be used by our response.
   if ("contentType" in query) {
     contentType = query["contentType"];
   }
   // optional size (in bytes) for generated file.
   if ("size" in query) {
     size = parseInt(query["size"]);
   }
   // optional range request check.
   if (request.hasHeader("range")) {
     version = "1.1";
     statusCode = 206;
     description = "Partial Content";
     // We'll only support simple range byte style requests.
     var [offset, total] = request.getHeader("range").slice("bytes=".length).split("-");
     // Enforce valid Number values.
     offset = parseInt(offset);
     offset = isNaN(offset) ? 0 : offset;
     // Same.
     total = parseInt(total);
     total = isNaN(total) ? 0 : total;
     // We'll need to original total size as part of the Content-Range header
     // value in our response.
     var originalSize = size;
     // If we have a total size requested, we must make sure to send that number
     // of bytes only (minus the start offset).
     if (total && total < size) {
       size = total - offset;
     } else if (offset) {
       // Looks like we just have a byte offset to deal with.
       size = size - offset;
     }
     // We specifically need to add a Content-Range header to all responses for
     // requests that include a range request header.
     contentRange = "bytes " + offset + "-" + (size - 1) + "/" + originalSize;
   }
   // optional rate (in bytes/s) at which to send the file.
   if ("rate" in query) {
     rate = parseInt(query["rate"]);
   }
   // The context for the responseHandler.
   var context = {
     response: response,
     state: {
       contentType: contentType,
       totalBytes: size,
       sentBytes: 0,
       rate: rate
     },
     timer: null
   };
   // The notify implementation for the timer.
   context.notify = handleResponse.bind(context);
   context.timer =
     Components.classes["@mozilla.org/timer;1"]
               .createInstance(Components.interfaces.nsITimer);
   // generate the content.
   response.setStatusLine(version, statusCode, description);
   response.setHeader("Content-Type", contentType, false);
   if (contentRange) {
     response.setHeader("Content-Range", contentRange, false);
   }
   response.setHeader("Content-Length", size.toString(), false);
   // initialize the timer and start writing out the response.
   context.timer.initWithCallback(
     context,
 ,
     Components.interfaces.nsITimer.TYPE_REPEATING_SLACK
   );
 }

The Tor Browser / annotate

dom/downloads/tests/serve_file.sjs@b8a032363ba2 (annotated)

dom/downloads/tests/serve_file.sjs