ms/blueprintsprocessor/modules/commons/message-lib/src/main/kotlin/org/onap/ccsdk/cds/blueprintsprocessor/message/service/KafkaBasicAuthMessageConsumerService.kt

   1 /*
   2  *  Copyright © 2019 IBM.
   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
  17 package org.onap.ccsdk.cds.blueprintsprocessor.message.service
  18
  19 import kotlinx.coroutines.channels.Channel
  20 import kotlinx.coroutines.delay
  21 import kotlinx.coroutines.launch
  22 import kotlinx.coroutines.runBlocking
  23 import org.apache.kafka.clients.CommonClientConfigs
  24 import org.apache.kafka.clients.consumer.Consumer
  25 import org.apache.kafka.clients.consumer.ConsumerConfig
  26 import org.apache.kafka.clients.consumer.KafkaConsumer
  27 import org.apache.kafka.common.serialization.StringDeserializer
  28 import org.onap.ccsdk.cds.blueprintsprocessor.message.KafkaBasicAuthMessageConsumerProperties
  29 import org.onap.ccsdk.cds.controllerblueprints.core.logger
  30 import java.time.Duration
  31 import kotlin.concurrent.thread
  32
  33 class KafkaBasicAuthMessageConsumerService(
  34         private val messageConsumerProperties: KafkaBasicAuthMessageConsumerProperties)
  35     : BlueprintMessageConsumerService {
  36
  37     private val channel = Channel<String>()
  38     private var kafkaConsumer: Consumer<String, String>? = null
  39     val log = logger(KafkaBasicAuthMessageConsumerService::class)
  40
  41     @Volatile
  42     var keepGoing = true
  43
  44     fun kafkaConsumer(additionalConfig: Map<String, Any>? = null): Consumer<String, String> {
  45         val configProperties = hashMapOf<String, Any>()
  46         configProperties[CommonClientConfigs.BOOTSTRAP_SERVERS_CONFIG] = messageConsumerProperties.bootstrapServers
  47         configProperties[ConsumerConfig.GROUP_ID_CONFIG] = messageConsumerProperties.groupId
  48         configProperties[ConsumerConfig.AUTO_OFFSET_RESET_CONFIG] = "latest"
  49         configProperties[ConsumerConfig.KEY_DESERIALIZER_CLASS_CONFIG] = StringDeserializer::class.java
  50         configProperties[ConsumerConfig.VALUE_DESERIALIZER_CLASS_CONFIG] = StringDeserializer::class.java
  51         if (messageConsumerProperties.clientId != null) {
  52             configProperties[ConsumerConfig.CLIENT_ID_CONFIG] = messageConsumerProperties.clientId!!
  53         }
  54         // TODO("Security Implementation based on type")
  55         /** add or override already set properties */
  56         additionalConfig?.let { configProperties.putAll(it) }
  57         /** Create Kafka consumer */
  58         return KafkaConsumer(configProperties)
  59     }
  60
  61     override suspend fun subscribe(additionalConfig: Map<String, Any>?): Channel<String> {
  62         /** get to topic names */
  63         val consumerTopic = messageConsumerProperties.topic?.split(",")?.map { it.trim() }
  64         check(!consumerTopic.isNullOrEmpty()) { "couldn't get topic information" }
  65         return subscribe(consumerTopic, additionalConfig)
  66     }
  67
  68
  69     override suspend fun subscribe(consumerTopic: List<String>, additionalConfig: Map<String, Any>?): Channel<String> {
  70         /** Create Kafka consumer */
  71         kafkaConsumer = kafkaConsumer(additionalConfig)
  72
  73         checkNotNull(kafkaConsumer) {
  74             "failed to create kafka consumer for " +
  75                     "server(${messageConsumerProperties.bootstrapServers})'s " +
  76                     "topics(${messageConsumerProperties.bootstrapServers})"
  77         }
  78
  79         kafkaConsumer!!.subscribe(consumerTopic)
  80         log.info("Successfully consumed topic($consumerTopic)")
  81
  82         thread(start = true, name = "KafkaConsumer") {
  83             keepGoing = true
  84             kafkaConsumer!!.use { kc ->
  85                 while (keepGoing) {
  86                     val consumerRecords = kc.poll(Duration.ofMillis(messageConsumerProperties.pollMillSec))
  87                     runBlocking {
  88                         consumerRecords?.forEach { consumerRecord ->
  89                             /** execute the command block */
  90                             consumerRecord.value()?.let {
  91                                 launch {
  92                                     if (!channel.isClosedForSend) {
  93                                         channel.send(it)
  94                                     } else {
  95                                         log.error("Channel is closed to receive message")
  96                                     }
  97                                 }
  98                             }
  99                         }
 100                     }
 101                 }
 102                 log.info("message listener shutting down.....")
 103             }
 104         }
 105         return channel
 106     }
 107
 108     override suspend fun shutDown() {
 109         /** stop the polling loop */
 110         keepGoing = false
 111         /** Close the Channel */
 112         channel.cancel()
 113         /** TO shutdown gracefully, need to wait for the maximum poll time */
 114         delay(messageConsumerProperties.pollMillSec)
 115     }
 116 }