Fix mock handler headers for resumable upload

Author: nicktindall

test/fixtures/gcs-fixture/src/main/java/fixture/gcs/GoogleCloudStorageHttpHandler.java

@@ -253,7 +253,7 @@ public void handle(final HttpExchange exchange) throws IOException {
                 if (updateResponse.rangeHeader() != null) {
                     exchange.getResponseHeaders().add("Range", updateResponse.rangeHeader().headerString());
                 }
-                exchange.getResponseHeaders().add("Content-Length", "0");
+                exchange.getResponseHeaders().add("x-goog-stored-content-length", String.valueOf(updateResponse.storedContentLength()));
                 exchange.sendResponseHeaders(updateResponse.statusCode(), -1);
             } else {
                 exchange.sendResponseHeaders(RestStatus.NOT_FOUND.getStatus(), -1);

test/fixtures/gcs-fixture/src/main/java/fixture/gcs/MockGcsBlobStore.java

@@ -117,10 +117,16 @@ UpdateResponse updateResumableUpload(String uploadId, HttpHeaderParser.ContentRa
             if (contentRange.hasRange() == false) {
                 // Content-Range: */... is a status check https://cloud.google.com/storage/docs/performing-resumable-uploads#status-check
                 if (existing.completed) {
-                    updateResponse.set(new UpdateResponse(RestStatus.OK.getStatus(), calculateRangeHeader(blobs.get(existing.path))));
+                    updateResponse.set(
+                        new UpdateResponse(
+                            RestStatus.OK.getStatus(),
+                            calculateRangeHeader(blobs.get(existing.path)),
+                            existing.contents.length()
+                        )
+                    );
                 } else {
                     final HttpHeaderParser.Range range = calculateRangeHeader(existing);
-                    updateResponse.set(new UpdateResponse(RESUME_INCOMPLETE, range));
+                    updateResponse.set(new UpdateResponse(RESUME_INCOMPLETE, range, existing.contents.length()));
                 }
                 return existing;
             } else {
@@ -146,11 +152,11 @@ UpdateResponse updateResumableUpload(String uploadId, HttpHeaderParser.ContentRa
                 // We just received the last chunk, update the blob and remove the resumable upload from the map
                 if (contentRange.hasSize() && updatedContent.length() == contentRange.size()) {
                     updateBlob(existing.path(), existing.ifGenerationMatch, updatedContent);
-                    updateResponse.set(new UpdateResponse(RestStatus.OK.getStatus(), null));
+                    updateResponse.set(new UpdateResponse(RestStatus.OK.getStatus(), null, updatedContent.length()));
                     return existing.update(BytesArray.EMPTY, true);
                 }
                 final ResumableUpload updated = existing.update(updatedContent, false);
-                updateResponse.set(new UpdateResponse(RESUME_INCOMPLETE, calculateRangeHeader(updated)));
+                updateResponse.set(new UpdateResponse(RESUME_INCOMPLETE, calculateRangeHeader(updated), updated.contents.length()));
                 return updated;
             }
         });
@@ -166,7 +172,7 @@ private static HttpHeaderParser.Range calculateRangeHeader(BlobVersion blob) {
         return blob.contents.length() > 0 ? new HttpHeaderParser.Range(0, blob.contents.length() - 1) : null;
     }
 
-    record UpdateResponse(int statusCode, HttpHeaderParser.Range rangeHeader) {}
+    record UpdateResponse(int statusCode, HttpHeaderParser.Range rangeHeader, long storedContentLength) {}
 
     void deleteBlob(String path) {
         blobs.remove(path);