Create a sink connector from Apache Kafka® to Snowflake
The Apache Kafka Connect® Snowflake sink connector enables you to move data from an Aiven for Apache Kafka® cluster to a Snowflake database. The full connector documentation is available in the dedicated GitHub repository.
See the full set of available parameters and configuration options in the connector's documentation.
Prerequisites
-
An Aiven for Apache Kafka® service with Apache Kafka Connect enabled or a dedicated Aiven for Apache Kafka Connect cluster.
-
Prepare the Snowflake account and collect the following information about the target Snowflake database:
-
SNOWFLAKE_URL
: The URL used to access the Snowflake account in the format ofACCOUNT_LOCATOR.REGION_ID.snowflakecomputing.com
where:ACCOUNT_LOCATOR
is the name of the account, more information are available in the dedicated Snowflake documentationREGION_ID
is the Id of the region where the Snowflake service is available, you can review the region Ids in the dedicated documentation
tipThe Snowflake account Id and region name can be obtained in the Snowflake UI by issuing the following query in a worksheet:
select current_account(), current_region()
-
SNOWFLAKE_USERNAME
: A valid Snowflake username with enough privileges to write data in the target database as mentioned in the prerequisite document. -
SNOWFLAKE_PRIVATE_KEY
: The private key associated to theSNOWFLAKE_USERNAME
as mentioned in the prerequisite document. -
SNOWFLAKE_PRIVATE_KEY_PASSPHRASE
: The private key passphrase -
SNOWFLAKE_DATABASE
: The target Snowflake database name -
SNOWFLAKE_SCHEMA
: The target Snowflake database schema name -
TOPIC_LIST
: The list of topics to sink divided by comma -
APACHE_KAFKA_HOST
: The hostname of the Apache Kafka service, only needed when using Avro as data format -
SCHEMA_REGISTRY_PORT
: The Apache Kafka's schema registry port, only needed when using Avro as data format -
SCHEMA_REGISTRY_USER
: The Apache Kafka's schema registry username, only needed when using Avro as data format -
SCHEMA_REGISTRY_PASSWORD
: The Apache Kafka's schema registry user password, only needed when using Avro as data format
-
Setup a Snowflake sink connector with Aiven Console
The following example demonstrates how to setup an Apache Kafka Connect® Snowflake sink connector using the Aiven Console.
Define an Apache Kafka Connect® configuration file
Define the connector configurations in a file (we'll refer to it with
the name snowflake_sink.json
) with the following content:
{
"name": "my-test-snowflake",
"connector.class": "com.snowflake.kafka.connector.SnowflakeSinkConnector",
"topics": "TOPIC_LIST",
"key.converter": "io.confluent.connect.avro.AvroConverter",
"key.converter.schema.registry.url": "https://APACHE_KAFKA_HOST:SCHEMA_REGISTRY_PORT",
"key.converter.basic.auth.credentials.source": "USER_INFO",
"key.converter.schema.registry.basic.auth.user.info": "SCHEMA_REGISTRY_USER:SCHEMA_REGISTRY_PASSWORD",
"value.converter": "io.confluent.connect.avro.AvroConverter",
"value.converter.schema.registry.url": "https://APACHE_KAFKA_HOST:SCHEMA_REGISTRY_PORT",
"value.converter.basic.auth.credentials.source": "USER_INFO",
"value.converter.schema.registry.basic.auth.user.info": "SCHEMA_REGISTRY_USER:SCHEMA_REGISTRY_PASSWORD",
"snowflake.url.name": "SNOWFLAKE_URL",
"snowflake.user.name": "SNOWFLAKE_USERNAME",
"snowflake.private.key": "SNOWFLAKE_PRIVATE_KEY",
"snowflake.private.key.passphrase": "SNOWFLAKE_PRIVATE_KEY_PASSPHRASE",
"snowflake.database.name": "SNOWFLAKE_DATABASE",
"snowflake.schema.name": "SNOWFLAKE_SCHEMA"
}
The configuration file contains the following entries:
name
: The connector nametopics
: The list of Apache Kafka® topics to sink to the Snowflake databasekey.converter
andvalue.converter
: defines the messages data format in the Apache Kafka topic. Theio.confluent.connect.avro.AvroConverter
converter translates messages from the Avro format. To retrieve the messages schema we use Aiven's Karapace schema registry as specified by theschema.registry.url
parameter and related credentials.
The key.converter
and value.converter
sections define how the topic
messages will be parsed and needs to be included in the connector
configuration.
When using Avro as source data format, set following parameters:
value.converter.schema.registry.url
: pointing to the Aiven for Apache Kafka schema registry URL in the form ofhttps://APACHE_KAFKA_HOST:SCHEMA_REGISTRY_PORT
with theAPACHE_KAFKA_HOST
andSCHEMA_REGISTRY_PORT
parameters retrieved in the previous step.value.converter.basic.auth.credentials.source
: to the valueUSER_INFO
, since you're going to login to the schema registry using username and password.value.converter.schema.registry.basic.auth.user.info
: passing the required schema registry credentials in the form ofSCHEMA_REGISTRY_USER:SCHEMA_REGISTRY_PASSWORD
with theSCHEMA_REGISTRY_USER
andSCHEMA_REGISTRY_PASSWORD
parameters retrieved in the previous step.
snowflake.url.name
: The URL to access the Snowflake servicesnowflake.user.name
: The connection usersnowflake.private.key
: The user's private keysnowflake.private.key.passphrase
: The private key passphrasesnowflake.database.name
: The Snowflake database namesnowflake.schema.name
: The Snowflake schema name
Create a Kafka Connect connector with the Aiven Console
To create a Kafka Connect connector:
-
Log in to the Aiven Console and select the Aiven for Apache Kafka® or Aiven for Apache Kafka Connect® service where the connector needs to be defined.
-
Select Connectors from the left sidebar.
-
Select Create New Connector, it is enabled only for services with Kafka Connect enabled.
-
Select Snowflake Sink.
-
In the Common tab, locate the Connector configuration text box and select on Edit.
-
Paste the connector configuration (stored in the
snowflake_sink.json
file) in the form. -
Select Apply.
noteThe Aiven Console parses the configuration file and fills the relevant UI fields. You can review the UI fields across the various tab and change them if necessary. The changes will be reflected in JSON format in the Connector configuration text box.
-
After all the settings are correctly configured, select Create connector.
-
Verify the connector status under the Connectors screen.
-
Verify the presence of the data in the target Snowflake database.
noteYou can also create connectors using the Aiven CLI command.
Example: Create a Snowflake sink connector on a topic in Avro format
The example creates an Snowflake sink connector with the following properties:
-
connector name:
my_snowflake_sink
-
source topics:
test
-
Snowflake database:
testdb
-
Snowflake schema:
testschema
-
Snowflake URL:
XX0000.eu-central-1.snowflakecomputing.com
-
Snowflake user:
testuser
-
User private key:
XXXXXXXYYY
ZZZZZZZZZZ
KKKKKKKKKK
YY -
User private key passphrase:
password123
The connector configuration is the following:
{
"name": "my_snowflake_sink",
"connector.class": "com.snowflake.kafka.connector.SnowflakeSinkConnector",
"key.converter": "io.confluent.connect.avro.AvroConverter",
"key.converter.schema.registry.url": "https://APACHE_KAFKA_HOST:SCHEMA_REGISTRY_PORT",
"key.converter.basic.auth.credentials.source": "USER_INFO",
"key.converter.schema.registry.basic.auth.user.info": "SCHEMA_REGISTRY_USER:SCHEMA_REGISTRY_PASSWORD",
"value.converter": "io.confluent.connect.avro.AvroConverter",
"value.converter.schema.registry.url": "https://APACHE_KAFKA_HOST:SCHEMA_REGISTRY_PORT",
"value.converter.basic.auth.credentials.source": "USER_INFO",
"value.converter.schema.registry.basic.auth.user.info": "SCHEMA_REGISTRY_USER:SCHEMA_REGISTRY_PASSWORD",
"topics": "test",
"snowflake.url.name": "XX0000.eu-central-1.snowflakecomputing.com",
"snowflake.user.name": "testkafka",
"snowflake.private.key": "XXXXXXXYYYZZZZZZZZZZKKKKKKKKKKYY",
"snowflake.private.key.passphrase": "password123",
"snowflake.database.name": "testdb",
"snowflake.schema.name": "testschema"
}
Example: Create a Snowflake sink connector on a topic with a JSON schema
If you have a topic named iot_measurements
containing the following
data in JSON format, with a defined JSON schema:
{
"schema": {
"type":"struct",
"fields":[{
"type":"int64",
"optional": false,
"field": "iot_id"
},{
"type":"string",
"optional": false,
"field": "metric"
},{
"type":"int32",
"optional": false,
"field": "measurement"
}]
},
"payload":{ "iot_id":1, "metric":"Temperature", "measurement":14}
}
{
"schema": {
"type":"struct",
"fields":[{
"type":"int64",
"optional": false,
"field": "iot_id"
},{
"type":"string",
"optional": false,
"field": "metric"
},{
"type":"int32",
"optional": false,
"field": "measurement"
}]
},
"payload":{"iot_id":2, "metric":"Humidity", "measurement":60}
}
Since the JSON schema needs to be defined in every message, there is a big overhead to transmit the information. To achieve a better performance in term of information-message ratio you should use the Avro format together with the Karapace schema registry provided by Aiven
You can sink the iot_measurements
topic to Snowflake with the
following connector configuration, after replacing the placeholders for
SNOWFLAKE_URL
, SNOWFLAKE_USERNAME
, SNOWFLAKE_PRIVATE_KEY
,
SNOWFLAKE_PRIVATE_KEY_PASSPHRASE
, SNOWFLAKE_DATABASE
and
SNOWFLAKE_SCHEMA
:
{
"name": "my-test-snowflake-1",
"connector.class": "com.snowflake.kafka.connector.SnowflakeSinkConnector",
"value.converter": "org.apache.kafka.connect.json.JsonConverter",
"topics": "iot_measurements",
"snowflake.url.name": "SNOWFLAKE_URL",
"snowflake.user.name": "SNOWFLAKE_USERNAME",
"snowflake.private.key": "SNOWFLAKE_PRIVATE_KEY",
"snowflake.private.key.passphrase": "SNOWFLAKE_PRIVATE_KEY_PASSPHRASE",
"snowflake.database.name": "SNOWFLAKE_DATABASE",
"snowflake.schema.name": "SNOWFLAKE_SCHEMA"
}
The configuration file contains the following peculiarities:
"topics": "iot_measurements"
: setting the topic to sink"value.converter": "org.apache.kafka.connect.json.JsonConverter"
: the message value is in JSON format with a schema, there is not key converter defined for the key since it's empty