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

   1 /*
   2  *  Copyright © 2019 IBM.
   3  *  Modifications Copyright © 2018-2019 AT&T Intellectual Property.
   4  *
   5  *  Licensed under the Apache License, Version 2.0 (the "License");
   6  *  you may not use this file except in compliance with the License.
   7  *  You may obtain a copy of the License at
   8  *
   9  *      http://www.apache.org/licenses/LICENSE-2.0
  10  *
  11  *  Unless required by applicable law or agreed to in writing, software
  12  *  distributed under the License is distributed on an "AS IS" BASIS,
  13  *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  14  *  See the License for the specific language governing permissions and
  15  *  limitations under the License.
  16  */
  17
  18 package org.onap.ccsdk.cds.blueprintsprocessor.message.service
  19
  20 import kotlinx.coroutines.channels.Channel
  21 import kotlinx.coroutines.delay
  22 import kotlinx.coroutines.launch
  23 import kotlinx.coroutines.runBlocking
  24 import org.apache.kafka.clients.CommonClientConfigs
  25 import org.apache.kafka.clients.consumer.Consumer
  26 import org.apache.kafka.clients.consumer.ConsumerConfig
  27 import org.apache.kafka.clients.consumer.KafkaConsumer
  28 import org.apache.kafka.common.serialization.ByteArrayDeserializer
  29 import org.apache.kafka.common.serialization.StringDeserializer
  30 import org.onap.ccsdk.cds.blueprintsprocessor.message.KafkaBasicAuthMessageConsumerProperties
  31 import org.onap.ccsdk.cds.controllerblueprints.core.logger
  32 import java.nio.charset.Charset
  33 import java.time.Duration
  34 import kotlin.concurrent.thread
  35
  36 open class KafkaBasicAuthMessageConsumerService(
  37         private val messageConsumerProperties: KafkaBasicAuthMessageConsumerProperties)
  38     : BlueprintMessageConsumerService {
  39
  40     val log = logger(KafkaBasicAuthMessageConsumerService::class)
  41
  42     val channel = Channel<String>()
  43     var kafkaConsumer: Consumer<String, ByteArray>? = null
  44
  45     @Volatile
  46     var keepGoing = true
  47
  48     fun kafkaConsumer(additionalConfig: Map<String, Any>? = null): Consumer<String, ByteArray> {
  49         val configProperties = hashMapOf<String, Any>()
  50         configProperties[CommonClientConfigs.BOOTSTRAP_SERVERS_CONFIG] = messageConsumerProperties.bootstrapServers
  51         configProperties[ConsumerConfig.GROUP_ID_CONFIG] = messageConsumerProperties.groupId
  52         configProperties[ConsumerConfig.ENABLE_AUTO_COMMIT_CONFIG] = messageConsumerProperties.autoCommit
  53         /**
  54          * earliest: automatically reset the offset to the earliest offset
  55          * latest: automatically reset the offset to the latest offset
  56          */
  57         configProperties[ConsumerConfig.AUTO_OFFSET_RESET_CONFIG] = messageConsumerProperties.autoOffsetReset
  58         configProperties[ConsumerConfig.KEY_DESERIALIZER_CLASS_CONFIG] = StringDeserializer::class.java
  59         configProperties[ConsumerConfig.VALUE_DESERIALIZER_CLASS_CONFIG] = ByteArrayDeserializer::class.java
  60         if (messageConsumerProperties.clientId != null) {
  61             configProperties[ConsumerConfig.CLIENT_ID_CONFIG] = messageConsumerProperties.clientId!!
  62         }
  63         /** To handle Back pressure, Get only configured record for processing */
  64         if (messageConsumerProperties.pollRecords > 0) {
  65             configProperties[ConsumerConfig.MAX_POLL_RECORDS_CONFIG] = messageConsumerProperties.pollRecords
  66         }
  67         // TODO("Security Implementation based on type")
  68         /** add or override already set properties */
  69         additionalConfig?.let { configProperties.putAll(it) }
  70         /** Create Kafka consumer */
  71         return KafkaConsumer(configProperties)
  72     }
  73
  74     override suspend fun subscribe(additionalConfig: Map<String, Any>?): Channel<String> {
  75         /** get to topic names */
  76         val consumerTopic = messageConsumerProperties.topic?.split(",")?.map { it.trim() }
  77         check(!consumerTopic.isNullOrEmpty()) { "couldn't get topic information" }
  78         return subscribe(consumerTopic, additionalConfig)
  79     }
  80
  81
  82     override suspend fun subscribe(consumerTopic: List<String>, additionalConfig: Map<String, Any>?): Channel<String> {
  83         /** Create Kafka consumer */
  84         kafkaConsumer = kafkaConsumer(additionalConfig)
  85
  86         checkNotNull(kafkaConsumer) {
  87             "failed to create kafka consumer for " +
  88                     "server(${messageConsumerProperties.bootstrapServers})'s " +
  89                     "topics(${messageConsumerProperties.bootstrapServers})"
  90         }
  91
  92         kafkaConsumer!!.subscribe(consumerTopic)
  93         log.info("Successfully consumed topic($consumerTopic)")
  94
  95         thread(start = true, name = "KafkaConsumer") {
  96             keepGoing = true
  97             kafkaConsumer!!.use { kc ->
  98                 while (keepGoing) {
  99                     val consumerRecords = kc.poll(Duration.ofMillis(messageConsumerProperties.pollMillSec))
 100                     log.info("Consumed Records : ${consumerRecords.count()}")
 101                     runBlocking {
 102                         consumerRecords?.forEach { consumerRecord ->
 103                             /** execute the command block */
 104                             consumerRecord.value()?.let {
 105                                 launch {
 106                                     if (!channel.isClosedForSend) {
 107                                         channel.send(String(it, Charset.defaultCharset()))
 108                                     } else {
 109                                         log.error("Channel is closed to receive message")
 110                                     }
 111                                 }
 112                             }
 113                         }
 114                     }
 115                 }
 116                 log.info("message listener shutting down.....")
 117             }
 118         }
 119         return channel
 120     }
 121
 122     override suspend fun shutDown() {
 123         /** stop the polling loop */
 124         keepGoing = false
 125         /** Close the Channel */
 126         channel.cancel()
 127         /** TO shutdown gracefully, need to wait for the maximum poll time */
 128         delay(messageConsumerProperties.pollMillSec)
 129     }
 130 }