1 /* 2 * Copyright 2022 Google LLC 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 package com.google.android.libraries.mobiledatadownload.internal.logging; 17 18 import com.google.common.base.Optional; 19 import com.google.common.util.concurrent.ListenableFuture; 20 import com.google.mobiledatadownload.internal.MetadataProto.FileGroupLoggingState; 21 import com.google.mobiledatadownload.internal.MetadataProto.SamplingInfo; 22 import java.util.List; 23 24 /** Interface for keeping track of state necessary for accurate logging. */ 25 public interface LoggingStateStore { 26 27 /** 28 * Gets the number of days since maintenance was last run and updates the timestamp for future 29 * calls. 30 * 31 * @return a future representing the number of days since maintenance was last run. If this method 32 * hasn't succeeded before, the future will complete with an absent Optional. The future may 33 * complete with (invalid) negative values. Future will fail with IOException if there was an 34 * issue reading or updating the value. 35 */ getAndResetDaysSinceLastMaintenance()36 public ListenableFuture<Optional<Integer>> getAndResetDaysSinceLastMaintenance(); 37 38 /** 39 * Increment the data usage stats for the file group. If there exists an entry which matches the 40 * GroupKey, version number and build id, then the data usage from dataUsageIncrements will be 41 * added to that, otherwise a new entry will be created. 42 */ incrementDataUsage(FileGroupLoggingState dataUsageIncrements)43 public ListenableFuture<Void> incrementDataUsage(FileGroupLoggingState dataUsageIncrements); 44 45 /** 46 * Returns a list of all the data usage increments grouped by GroupKey, build id and version 47 * number. 48 */ getAndResetAllDataUsage()49 public ListenableFuture<List<FileGroupLoggingState>> getAndResetAllDataUsage(); 50 51 /** Resets all LoggingStateStore state. */ clear()52 public ListenableFuture<Void> clear(); 53 54 /** 55 * Gets info necessary for stable sampling. Callers are responsible for ensuring that stable 56 * sampling is enabled. 57 * 58 * <p>If the stable sampling random number hasn't been persisted yet, this will populate it before 59 * returning. 60 */ getStableSamplingInfo()61 public ListenableFuture<SamplingInfo> getStableSamplingInfo(); 62 } 63