4.0

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Elastic6

A Kafka Connect sink connector for writing records from Kafka to Elastic.

Requires:

  • Elastic 6+

KCQL support 

The following KCQL is supported:

INSERT | UPSERT 
INTO <elastic_index >
SELECT FIELD, ... 
FROM kafka_topic
[PK FIELD,...]
[WITHDOCTYPE=<your_document_type>]
[WITHINDEXSUFFIX=<your_suffix>]

Examples:

-- Insert mode, select all fields from topicA and write to indexA
INSERT INTO indexA SELECT * FROM topicA

-- Insert mode, select 3 fields and rename from topicB 
-- and write to indexB
INSERT INTO indexB SELECT x AS a, y, zc FROM topicB PK y

-- UPSERT
UPSERT INTO indexC SELECT id, string_field FROM topicC PK id

Concepts 

Primary Keys 

The PK keyword can be used to specify the fields which will be used for the key value. The field values will be concatenated and separated by a -. If no fields are set the topic name, partition and message offset are used.

Document Type 

WITHDOCTYPE allows you to associate a document type to the document inserted.

Index Suffix 

WITHINDEXSUFFIX allows you to specify a suffix to your index and we support date format.

Example:

WITHINDEXSUFFIX=_suffix_{YYYY-MM-dd}

Error polices 

The connector supports Error polices .

Auto Index Creation 

The Sink will automatically create missing indexes at startup.

Quickstart 

Launch the stack 


  1. Copy the docker-compose file.
  2. Bring up the stack.
export CONNECTOR=elastic6
docker-compose up -d elastic

Start the connector 

If you are using Lenses, login into Lenses and navigate to the connectors page , select Elastic as the sink and paste the following:

name=elastic
connector.class=com.datamountaineer.streamreactor.connect.elastic6.ElasticSinkConnector
tasks.max=1
topics=orders
connect.elastic.protocol=http
connect.elastic.hosts=elastic
connect.elastic.port=9200
connect.elastic.cluster.name=elasticsearch
connect.elastic.kcql=INSERT INTO orders SELECT * FROM orders
connect.progress.enabled=true

To start the connector without using Lenses, log into the fastdatadev container:


docker exec -ti fastdata /bin/bash

and create a connector.properties file containing the properties above.

Create the connector, with the connect-cli :

connect-cli create elastic < connector.properties

Wait a for the connector to start and check its running:

connect-cli status elastic

Inserting test data 

In the to fastdata container start the kafka producer shell:


kafka-avro-console-producer \
 --broker-list localhost:9092 --topic orders \
 --property value.schema='{"type":"record","name":"myrecord","fields":[{"name":"id","type":"int"},{"name":"created","type":"string"},{"name":"product","type":"string"},{"name":"price","type":"double"}, {"name":"qty", "type":"int"}]}'

the console is now waiting for your input, enter the following:


{"id": 1, "created": "2016-05-06 13:53:00", "product": "OP-DAX-P-20150201-95.7", "price": 94.2, "qty":100}

Check for data in Elastic 

Login to the elastic container:

 docker exec -ti elastic bin/elasticsearch-sql-cli

Run the following:

 SELECT * FROM orders;

Clean up 

Bring down the stack:

docker-compose down

Options 

NameDescriptionTypeDefault Value
connect.elastic.protocolURL protocol (http, https)stringhttp
connect.elastic.hostsList of hostnames for Elastic Search cluster node, not including protocol or port.stringlocalhost
connect.elastic.portPort on which Elastic Search node listens onstring9300
connect.elastic.tableprefixTable prefix (optional)string
connect.elastic.cluster.nameName of the elastic search cluster, used in local mode for setting the connectionstringelasticsearch
connect.elastic.write.timeoutThe time to wait in millis. Default is 5 minutes.int300000
connect.elastic.batch.sizeHow many records to process at one time. As records are pulled from Kafka it can be 100k+ which will not be feasible to throw at Elastic search at onceint4000
connect.elastic.use.http.usernameUsername if HTTP Basic Auth required default is null.string
connect.elastic.use.http.passwordPassword if HTTP Basic Auth required default is null.string
connect.elastic.error.policySpecifies the action to be taken if an error occurs while inserting the data There are two available options: NOOP - the error is swallowed THROW - the error is allowed to propagate. RETRY - The exception causes the Connect framework to retry the message. The number of retries is based on The error will be logged automaticallystringTHROW
connect.elastic.max.retriesThe maximum number of times to try the write again.int20
connect.elastic.retry.intervalThe time in milliseconds between retries.int60000
connect.elastic.kcqlKCQL expression describing field selection and routes.string
connect.elastic.pk.separatorSeparator used when have more that one field in PKstring-
connect.progress.enabledEnables the output for how many records have been processedbooleanfalse