Kafka Indexing Service - Cyrillic Issue

Issue while loading data through Kafka Indexing Service.
Kafka Indexing Service does not start any ingestion task if data source name is in Cyrillic (works fine if Latin).

Overlord logs (there are some missing characters in taskId):

Dec 10 03:58:37 ub druid-overload.sh[1450]: 2018-12-10T00:58:37,143 INFO [KafkaIndexTaskClient-Средняя заработная плата-0] io.druid.java.util.http.client.pool.ChannelResourceFactory - Generating: http://ub:8101

Dec 10 03:58:37 ub druid-overload.sh[1450]: 2018-12-10T00:58:37,151 WARN [KafkaIndexTaskClient-Средняя заработная плата-0] io.druid.indexing.kafka.KafkaIndexTaskClient - Expected worker to have taskId [index_kafka_Средняя заработная плата_419f54082b9c6c0_ckoppdmd] but has taskId [index_kafka_ _419f54082b9c6c0_ckoppdmd], will retry in [5]s

Dec 10 03:58:42 ub druid-overload.sh[1450]: 2018-12-10T00:58:42,156 INFO [KafkaIndexTaskClient-Средняя заработная плата-0] io.druid.java.util.http.client.pool.ChannelResourceFactory - Generating: http://ub:8101

Dec 10 03:58:42 ub druid-overload.sh[1450]: 2018-12-10T00:58:42,177 WARN [KafkaIndexTaskClient-Средняя заработная плата-0] io.druid.indexing.kafka.KafkaIndexTaskClient - Expected worker to have taskId [index_kafka_Средняя заработная плата_419f54082b9c6c0_ckoppdmd] but has taskId [index_kafka_ _419f54082b9c6c0_ckoppdmd], will retry in [5]s

Is this a bug or a configuration issue?

Here is my supervisor schema:

{

"type": "kafka",

"dataSchema": {

    "dataSource": "Средняя заработная плата",

    "parser": {

        "type": "string",

        "parseSpec": {

            "format": "json",

            "timestampSpec": {

                "column": "Период",

                "format": "auto"

            },

            "dimensionsSpec": {

                "dimensions": [

                    "Страна",

                    "Федеральный округ",

                    "Субъект",

                    "Отрасль",

                    "Группа учреждений",

                    "Район",

                    "Организация",

                    "Должность",

                    "Категория должностей"

                ]

            }

        }

    },

    "metricsSpec": [

        {

            "type": "doubleSum",

            "name": "Средняя численность списочного со",

            "fieldName": "Средняя численность списочного со"

        },

        {

            "type": "doubleSum",

            "name": "Окладная часть",

            "fieldName": "Окладная часть"

        },

        {

            "type": "doubleSum",

            "name": "Компенсац характера",

            "fieldName": "Компенсац характера"

        },

        {

            "type": "doubleSum",

            "name": "Прочие",

            "fieldName": "Прочие"

        },

        {

            "type": "doubleSum",

            "name": "Бюджет",

            "fieldName": "Бюджет"

        },

        {

            "type": "doubleSum",

            "name": "Приносящая доход деятельность",

            "fieldName": "Приносящая доход деятельность"

        },

        {

            "type": "doubleSum",

            "name": "Зарплата общ",

            "fieldName": "Зарплата общ"

        },

        {

            "type": "doubleSum",

            "name": "Стимулир характера",

            "fieldName": "Стимулир характера"

        },

        {

            "type": "doubleSum",

            "name": "Бюджет окладная часть",

            "fieldName": "Бюджет окладная часть"

        },

        {

            "type": "doubleSum",

            "name": "Бюджет компенсац характера",

            "fieldName": "Бюджет компенсац характера"

        },

        {

            "type": "doubleSum",

            "name": "Бюджет стимулир характера",

            "fieldName": "Бюджет стимулир характера"

        },

        {

            "type": "doubleSum",

            "name": "Бюджет прочие",

            "fieldName": "Бюджет прочие"

        }

    ],

    "granularitySpec": {

        "type": "uniform",

        "segmentGranularity": "MONTH",

        "queryGranularity": "NONE",

        "rollup": true

    },

    "transformSpec": {

        "transforms": [

            {

                "type": "expression",

                "name": "Страна",

                "expression": "concat('Российская Федерация')"

            },

            {

                "type": "expression",

                "name": "Федеральный округ",

                "expression": "concat('Северо-Западный федеральный округ')"

            },

            {

                "type": "expression",

                "name": "Субъект",

                "expression": "concat('Санкт-Петербург')"

            }

        ]

    }

},

"tuningConfig": {

    "type": "kafka",

    "reportParseExceptions": true

},

"ioConfig": {

    "topic": "mean-wages",

    "replicas": 2,

    "taskDuration": "PT5M",

    "completionTimeout": "PT10M",

    "consumerProperties": {

        "bootstrap.servers": "localhost:9092"

    }

}

}

Environment:

$ java -version

openjdk version “1.8.0_191”

OpenJDK Runtime Environment (build 1.8.0_191-8u191-b12-0ubuntu0.18.04.1-b12)

OpenJDK 64-Bit Server VM (build 25.191-b12, mixed mode)

$ uname -a

Linux ub 4.15.0-42-generic #45-Ubuntu SMP Thu Nov 15 19:32:57 UTC 2018 x86_64 x86_64 x86_64 GNU/Linux

$ localectl status

System Locale: LANG=en_US.UTF-8

              LANGUAGE=en_US

   VC Keymap: n/a

  X11 Layout: us,ru

   X11 Model: pc105

 X11 Variant: ,

 X11 Options: grp:toggle,grp_led:scroll

Same error for:

$ localectl status

System Locale: LANG=ru_RU.UTF-8

   VC Keymap: n/a

  X11 Layout: us

   X11 Model: pc105

$ lsb_release -a

LSB Version: core-9.20170808ubuntu1-noarch:security-9.20170808ubuntu1-noarch

Distributor ID: Ubuntu

Description: Ubuntu 18.04.1 LTS

Release: 18.04

Codename: bionic

druid version 0.12.3

Thanks!

A github issue has been created for this: https://github.com/apache/incubator-druid/issues/6718