Provide gPRC data transport protocol define (#25)
diff --git a/language-agent/Meter.proto b/language-agent/Meter.proto
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+/*
+ * 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";
+
+option java_multiple_files = true;
+option java_package = "org.apache.skywalking.apm.network.language.agent.v3";
+
+import "common/Common.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.
+ rpc collect (stream MeterData) 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.
+ // Also, could use Int32.MIN_VALUE to represent negative infinity.
+ int32 bucket = 1;
+ int64 count = 2;
+}
+
+// Meter single value
+message MeterSingleValue {
+ // Meter name
+ string name = 1;
+ // Labels
+ repeated Label labels = 2;
+ // Single value
+ int64 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;
+}
