[pinpoint-apm#182] Support ServiceConfig spec( https://github.com/grp…

…c/grpc/blob/master/doc/service_config.md )

lib/client/grpc/service-config-builder.js

@@ -0,0 +1,40 @@
+/**
+ * Pinpoint Node.js Agent
+ * Copyright 2020-present NAVER Corp.
+ * Apache License v2.0
+ */
+
+'use strict'
+
+class ServiceConfig {
+    constructor(agentServiceConfig, metadataServiceConfig) {
+        this.agentServiceConfig = agentServiceConfig
+        this.metadataServiceConfig = metadataServiceConfig
+    }
+
+    getAgentServiceConfig() {
+        return this.agentServiceConfig
+    }
+
+    getMetadataServiceConfig() {
+        return this.metadataServiceConfig
+    }
+}
+
+class ServiceConfigBuilder {
+    setAgentServiceConfig(config) {
+        this.agentServiceConfig = config
+        return this
+    }
+
+    setMetadataServiceConfig(config) {
+        this.metadataServiceConfig = config
+        return this
+    }
+
+    build() {
+        return new ServiceConfig(this.agentServiceConfig, this.metadataServiceConfig)
+    }
+}
+
+module.exports = ServiceConfigBuilder

lib/config.js

@@ -12,6 +12,7 @@ const defaultConfig = require('./pinpoint-config-default')
 const log = require('./utils/logger')
 const { setLog } = require('./supports')
 const { makeLogLevelLog } = require('./utils/log/log-level-logger')
+const ServiceConfigBuilder = require('./client/grpc/service-config-builder')
 
 const valueOfString = (envName) => {
   return () => {
@@ -140,6 +141,8 @@ const configurationValueValidations = {
   }
 }
 
+const defaultServiceConfigBuilder = new ServiceConfigBuilder()
+
 const init = (initOptions = {}) => {
   agentConfig = Object.assign({},
     readConfigJson(defaultConfig),
@@ -164,6 +167,13 @@ const init = (initOptions = {}) => {
   for (const [key, validation] of Object.entries(configurationValueValidations)) {
     validation()
   }
+
+  if (initOptions['grpc.service_config'] && initOptions['grpc.service_config'].name === 'ServiceConfig') {
+    const config = initOptions['grpc.service_config']
+    agentConfig.serviceConfig = config
+  } else {
+    agentConfig.serviceConfig = defaultServiceConfigBuilder.build()
+  }
 }
 
 const readFromEnv = () => {