1 files changed, 27 insertions, 24 deletions
diff --git a/src/libstore/http-binary-cache-store.cc b/src/libstore/http-binary-cache-store.cc
index bdcd2fd3998b..9d31f77c921f 100644
--- a/src/libstore/http-binary-cache-store.cc
+++ b/src/libstore/http-binary-cache-store.cc
@@ -13,17 +13,12 @@ private:
 
     Path cacheUri;
 
-    Pool<Downloader> downloaders;
-
 public:
 
     HttpBinaryCacheStore(
         const Params & params, const Path & _cacheUri)
         : BinaryCacheStore(params)
         , cacheUri(_cacheUri)
-        , downloaders(
-            std::numeric_limits<size_t>::max(),
-            []() { return makeDownloader(); })
     {
         if (cacheUri.back() == '/')
             cacheUri.pop_back();
@@ -54,12 +49,11 @@ protected:
     bool fileExists(const std::string & path) override
     {
         try {
-            auto downloader(downloaders.get());
-            DownloadOptions options;
-            options.showProgress = DownloadOptions::no;
-            options.head = true;
-            options.tries = 5;
-            downloader->download(cacheUri + "/" + path, options);
+            DownloadRequest request(cacheUri + "/" + path);
+            request.showProgress = DownloadRequest::no;
+            request.head = true;
+            request.tries = 5;
+            getDownloader()->download(request);
             return true;
         } catch (DownloadError & e) {
             /* S3 buckets return 403 if a file doesn't exist and the
@@ -75,20 +69,29 @@ protected:
         throw UploadToHTTP("uploading to an HTTP binary cache is not supported");
     }
 
-    std::shared_ptr<std::string> getFile(const std::string & path) override
+    void getFile(const std::string & path,
+        std::function<void(std::shared_ptr<std::string>)> success,
+        std::function<void(std::exception_ptr exc)> failure) override
     {
-        auto downloader(downloaders.get());
-        DownloadOptions options;
-        options.showProgress = DownloadOptions::no;
-        options.tries = 5;
-        options.baseRetryTimeMs = 1000;
-        try {
-            return downloader->download(cacheUri + "/" + path, options).data;
-        } catch (DownloadError & e) {
-            if (e.error == Downloader::NotFound || e.error == Downloader::Forbidden)
-                return 0;
-            throw;
-        }
+        DownloadRequest request(cacheUri + "/" + path);
+        request.showProgress = DownloadRequest::no;
+        request.tries = 8;
+
+        getDownloader()->enqueueDownload(request,
+            [success](const DownloadResult & result) {
+                success(result.data);
+            },
+            [success, failure](std::exception_ptr exc) {
+                try {
+                    std::rethrow_exception(exc);
+                } catch (DownloadError & e) {
+                    if (e.error == Downloader::NotFound || e.error == Downloader::Forbidden)
+                        return success(0);
+                    failure(exc);
+                } catch (...) {
+                    failure(exc);
+                }
+            });
     }
 
 };