xref: /aosp_15_r20/external/downloader/src/main/proto/download_metadata.proto (revision 2b3ec505d2eb42ded0bcac2cc02f08e691c7d592)
1*2b3ec505SXin Li// Copyright 2021 The Android Open Source Project
2*2b3ec505SXin Li//
3*2b3ec505SXin Li// Licensed under the Apache License, Version 2.0 (the "License");
4*2b3ec505SXin Li// you may not use this file except in compliance with the License.
5*2b3ec505SXin Li// You may obtain a copy of the License at
6*2b3ec505SXin Li//
7*2b3ec505SXin Li//      http://www.apache.org/licenses/LICENSE-2.0
8*2b3ec505SXin Li//
9*2b3ec505SXin Li// Unless required by applicable law or agreed to in writing, software
10*2b3ec505SXin Li// distributed under the License is distributed on an "AS IS" BASIS,
11*2b3ec505SXin Li// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12*2b3ec505SXin Li// See the License for the specific language governing permissions and
13*2b3ec505SXin Li// limitations under the License.
14*2b3ec505SXin Li
15*2b3ec505SXin Lisyntax = "proto2";
16*2b3ec505SXin Li
17*2b3ec505SXin Lipackage android.downloader;
18*2b3ec505SXin Li
19*2b3ec505SXin Lioption java_multiple_files = true;
20*2b3ec505SXin Lioption java_package = "com.google.android.downloader";
21*2b3ec505SXin Lioption java_outer_classname = "DownloadMetadataProtoOuter";
22*2b3ec505SXin Li
23*2b3ec505SXin Li// Message encoding download metadata. May be persisted by implementations of
24*2b3ec505SXin Li// DownloadDestination (e.g. ProtoFileDownloadDestination) so that interrupted
25*2b3ec505SXin Li// downloads can be safely resumed.
26*2b3ec505SXin Limessage DownloadMetadataProto {
27*2b3ec505SXin Li  // The opaque content tag associated with the download. Commonly this
28*2b3ec505SXin Li  // is a checksum or hash of the actual data. However, the client should never
29*2b3ec505SXin Li  // attempt to infer any properties about this string, and should instead
30*2b3ec505SXin Li  // treat it as a token to be persisted and returned unaltered. This tag
31*2b3ec505SXin Li  // is used to ensure the underlying HTTP resource did not change across
32*2b3ec505SXin Li  // requests.
33*2b3ec505SXin Li  optional string content_tag = 1;
34*2b3ec505SXin Li
35*2b3ec505SXin Li  // The UNIX epoch timestamp, in seconds, for when the resource the download
36*2b3ec505SXin Li  // targets was last modified. This timestamp is used to determine if the
37*2b3ec505SXin Li  // underlying HTTP resource changed across requests.
38*2b3ec505SXin Li  optional int64 last_modified_time_seconds = 2;
39*2b3ec505SXin Li}