implemented download tokens

server/routes/download.js

@@ -1,53 +1,14 @@
 const storage = require('../storage');
-const mozlog = require('../log');
-const log = mozlog('send.download');
-const { statDownloadEvent } = require('../amplitude');
 
 module.exports = async function(req, res) {
   const id = req.params.id;
   try {
-    const meta = req.meta;
-    const contentLength = await storage.length(id);
-    const fileStream = await storage.get(id);
-    let cancelled = false;
-
-    req.on('aborted', () => {
-      cancelled = true;
-      fileStream.destroy();
-    });
-
+    const { length, stream } = await storage.get(id);
     res.writeHead(200, {
       'Content-Type': 'application/octet-stream',
-      'Content-Length': contentLength
-    });
-    fileStream.pipe(res).on('finish', async () => {
-      if (cancelled) {
-        return;
-      }
-
-      const dl = meta.dl + 1;
-      const dlimit = meta.dlimit;
-      const ttl = await storage.ttl(id);
-      statDownloadEvent({
-        id,
-        ip: req.ip,
-        country: req.geo.country,
-        state: req.geo.state,
-        owner: meta.owner,
-        download_count: dl,
-        ttl,
-        agent: req.ua.browser.name || req.ua.ua.substring(0, 6)
-      });
-      try {
-        if (dl >= dlimit) {
-          await storage.kill(id);
-        } else {
-          await storage.incrementField(id, 'dl');
-        }
-      } catch (e) {
-        log.info('StorageError:', id);
-      }
+      'Content-Length': length
     });
+    stream.pipe(res);
   } catch (e) {
     res.sendStatus(404);
   }