| // Copyright 2018 The LUCI Authors. |
| // |
| // Licensed under the Apache License, Version 2.0 (the "License"); |
| // you may not use this file except in compliance with the License. |
| // You may obtain a copy of the License at |
| // |
| // http://www.apache.org/licenses/LICENSE-2.0 |
| // |
| // Unless required by applicable law or agreed to in writing, software |
| // distributed under the License is distributed on an "AS IS" BASIS, |
| // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| // See the License for the specific language governing permissions and |
| // limitations under the License. |
| |
| package gitiles |
| |
| import ( |
| "context" |
| |
| "google.golang.org/grpc" |
| "google.golang.org/protobuf/proto" |
| |
| "go.chromium.org/luci/common/errors" |
| "go.chromium.org/luci/common/proto/git" |
| "go.chromium.org/luci/common/proto/gitiles" |
| ) |
| |
| // DefaultLimit is the default maximum number of commits to load. |
| // It is used in PagingLog. |
| const DefaultLimit = 1000 |
| |
| // Helper functions for Gitiles.Log RPC. |
| |
| // PagingLog is a wrapper around Gitiles.Log RPC that pages though commits. |
| // If req.PageToken is not empty, paging will continue from there. |
| // |
| // req.PageSize specifies maximum number of commits to load in each page. |
| // |
| // Limit specifies the maximum number of commits to load. |
| // 0 means use DefaultLimit. |
| func PagingLog(ctx context.Context, client pagingLogClient, req *gitiles.LogRequest, limit int, opts ...grpc.CallOption) ([]*git.Commit, error) { |
| // req needs to mutate, so clone it. |
| req = proto.Clone(req).(*gitiles.LogRequest) |
| |
| switch { |
| case limit < 0: |
| return nil, errors.New("limit must not be negative") |
| case limit == 0: |
| limit = DefaultLimit |
| } |
| |
| var combinedLog []*git.Commit |
| for { |
| remaining := limit - len(combinedLog) |
| if remaining <= 0 { |
| break |
| } |
| if req.PageSize == 0 || remaining < int(req.PageSize) { |
| // Do not fetch more than we need. |
| req.PageSize = int32(remaining) |
| } |
| |
| res, err := client.Log(ctx, req, opts...) |
| if err != nil { |
| return combinedLog, err |
| } |
| |
| // req was capped, so this should not exceed limit. |
| combinedLog = append(combinedLog, res.Log...) |
| // There may be fewer commits in the log than the limit given, |
| // if so, NextPageToken should be missing. |
| if res.NextPageToken == "" { |
| break |
| } |
| req.PageToken = res.NextPageToken |
| } |
| return combinedLog, nil |
| } |
| |
| type pagingLogClient interface { |
| Log(context.Context, *gitiles.LogRequest, ...grpc.CallOption) (*gitiles.LogResponse, error) |
| } |