/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You 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.
 *
 */

syntax = "proto3";

package skywalking.v3;

option java_multiple_files = true;
option java_package = "org.apache.skywalking.apm.network.language.agent.v3";
option go_package = "skywalking.apache.org/repo/goapi/collect/language/agent/v3";

import "common/Command.proto";

service MeterReportService {
    // Meter data is reported in a certain period. The agent/SDK should report all collected metrics in this period through one stream.
    // The whole stream is an input data set, client should onComplete the stream per report period.
    rpc collect (stream MeterData) returns (Commands) {
    }

    // Reporting meter data in bulk mode as MeterDataCollection.
    // By using this, each one in the stream would be treated as a complete input for MAL engine,
    // comparing to `collect (stream MeterData)`, which is using one stream as an input data set.
    rpc collectBatch (stream MeterDataCollection) returns (Commands) {
    }
}

// Label of the meter
message Label {
    string name = 1;
    string value = 2;
}

// The histogram element definition. It includes the bucket lower boundary and the count in the bucket.
message MeterBucketValue {
    // The value represents the min value of the bucket,
    // the  upper boundary is determined by next MeterBucketValue$bucket,
    // if it doesn't exist, the upper boundary is positive infinity.
    double bucket = 1;
    int64 count = 2;
    // If is negative infinity, the value of the bucket is invalid
    bool isNegativeInfinity = 3;
}

// Meter single value
message MeterSingleValue {
    // Meter name
    string name = 1;
    // Labels
    repeated Label labels = 2;
    // Single value
    double value = 3;
}

// Histogram
message MeterHistogram {
    // Meter name
    string name = 1;
    // Labels
    repeated Label labels = 2;
    // Customize the buckets
    repeated MeterBucketValue values = 3;
}

// Single meter data, if the same metrics have a different label, they will separate.
message MeterData {
    // Meter data could be a single value or histogram.
    oneof metric {
        MeterSingleValue singleValue = 1;
        MeterHistogram histogram = 2;
    }
    // Service name, be set value in the first element in the stream-call.
    string service = 3;
    // Service instance name, be set value in the first element in the stream-call.
    string serviceInstance = 4;
    // Meter data report time, be set value in the first element in the stream-call.
    int64 timestamp = 5;
}

message MeterDataCollection {
    repeated MeterData meterData = 1;
}
