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Kudu Sink Connector Configuration Properties

To use this connector, specify the name of the connector class in the connector.class configuration property.

connector.class=io.confluent.connect.kudu.KuduSinkConnector

Connector-specific configuration properties are described below.

Database Connection Security

In the connector configuration you will notice there are no security parameters. This is because SSL is not part of the JDBC standard and will depend on the JDBC driver in use. In general, you will need to configure SSL via the connection.url parameter. In Kudu database specifically, we are using Impala JDBC driver, and you need to set up a LDAP server to do username plus password authentication. Pass the Impala server hostname and port and Kudu database name to Kudu connector, And connection.url will be automatically generated, which would be something resemble:

connection.url="jdbc:impala://<Impala server name>:<Impala server port>/<Kudu database name>"

Please check the following links for setting up the LDAP server:

Once you set up the LDAP server and have Kudu and Impala deployed properly, complete the following steps:

  1. Start Impala daemon with the following flags:

    --enable_ldap_auth=true --ldap_uri=<LDAP URI> --ldap_bind_pattern="uid=#UID,dc=<Your DC in LDAP server>..." --ldap_passwords_in_clear_ok

  2. Insert in your LDAP URI and DCs in your LDAP server.

    LDAP URI should resemble: ldap://<LDAP server IP>:10389.

Connection

impala.server

The server address to use to format JDBC URL for connection

  • Type: string
  • Importance: high
impala.port

The port to use to format JDBC URL for connection; By default, Impala uses port 21050.

  • Type: int
  • Default: 21050
  • Valid Values: [0,…]
  • Importance: high
kudu.database

The Kudu database to connect

  • Type: string
  • Default: default
  • Importance: high
impala.ldap.user

Username to do LDAP authentication with Impala

  • Type: string
  • Importance: high
impala.ldap.password

Password to do LDAP authentication with Impala

  • Type: password
  • Importance: high
kudu.tablet.replicas

The number of replicas of Kudu tablets

  • Type: int
  • Default: 3
  • Valid Values: [1,…]
  • Importance: medium

Writes

insert.mode

The insertion mode to use. Supported modes are:

insert Use standard SQL INSERT statements.

update Use the appropriate update semantics for the target database if it is supported by the connector, for example,``UPDATE``.

  • Type: string
  • Default: insert
  • Valid Values: [insert, upsert, update]
  • Importance: high
batch.size

Specifies how many records to attempt to batch together for insertion into the destination table, when possible.

  • Type: int
  • Default: 3000
  • Valid Values: [0,…]
  • Importance: medium

Data Mapping

table.name.format

A format string for the destination table name, which may contain ‘${topic}’ as a placeholder for the originating topic name.

For example, kafka_${topic} for the topic ‘orders’ will map to the table name ‘kafka_orders’.

  • Type: string
  • Default: ${topic}
  • Importance: medium
pk.mode

The primary key mode, also refer to pk.fields documentation for interplay. Supported modes are:

none No keys utilized.

kafka Kafka coordinates are used as the PK.

record_key Field(s) from the record key are used, which may be a primitive or a struct.

record_value Field(s) from the record value are used, which must be a struct.

  • Type: string
  • Default: none
  • Valid Values: [none, kafka, record_key, record_value]
  • Importance: high
pk.fields

List of comma-separated primary key field names. The runtime interpretation of this config depends on the pk.mode:

none Ignored as no fields are used as primary key in this mode.

kafka Must be a trio representing the Kafka coordinates, defaults to __connect_topic,__connect_partition,__connect_offset if empty.

record_key If empty, all fields from the key struct will be used, otherwise used to extract the desired fields - for primitive key only a single field name must be configured.

record_value If empty, all fields from the value struct will be used, otherwise used to extract the desired fields.

  • Type: list
  • Default: “”
  • Importance: medium
fields.whitelist

List of comma-separated record value field names. If empty, all fields from the record value are utilized, otherwise used to filter to the desired fields.

Note

pk.fields is applied independently in the context of which field(s) form the primary key columns in the destination database, while this configuration is applicable for the other columns.

  • Type: list
  • Default: “”
  • Importance: medium

SQL/DDL Support

auto.create

Whether to automatically create the destination table based on record schema if it is found to be missing by issuing CREATE.

  • Type: boolean
  • Default: false
  • Importance: medium
auto.evolve

Whether to automatically add columns in the table schema when found to be missing relative to the record schema by issuing ALTER.

  • Type: boolean
  • Default: false
  • Importance: medium
quote.sql.identifiers

When to quote table names, column names, and other identifiers in SQL statements. For backward compatibility, the default is ‘always’.

  • Type: string
  • Default: ALWAYS
  • Importance: medium

Retries

max.retries

The maximum number of times to retry on errors before failing the task.

  • Type: int
  • Default: 10
  • Valid Values: [0,…]
  • Importance: medium
retry.backoff.ms

The time in milliseconds to wait following an error before a retry attempt is made.

  • Type: int
  • Default: 3000
  • Valid Values: [0,…]
  • Importance: medium

Confluent Platform license

confluent.topic.bootstrap.servers

A list of host/port pairs to use for establishing the initial connection to the Kafka cluster used for licensing. All servers in the cluster will be discovered from the initial connection. This list should be in the following form:

host1:port1,host2:port2,...

Since these servers are just used for the initial connection to discover the full cluster membership (which may change dynamically), this list need not contain the full set of servers (you may want more than one, though, in case a server is down).

  • Type: list
  • Importance: high
confluent.topic

Name of the Kafka topic used for Confluent Platform configuration, including licensing information.

  • Type: string
  • Default: _confluent-command
  • Importance: low
confluent.topic.replication.factor

The replication factor for the Kafka topic used for Confluent Platform configuration, including licensing information. This is used only if the topic does not already exist, and the default of 3 is appropriate for production use. If you are using a development environment with less than 3 brokers, you must set this to the number of brokers (often 1).

  • Type: int
  • Default: 3
  • Importance: low

Confluent license properties

Tip

While it is possible to include license-related properties in the connector configuration, starting with Confluent Platform version 6.0, you can now put license-related properties in the Connect worker configuration instead of in each connector configuration.

Note

This connector is proprietary and requires a license. The license information is stored in the _confluent-command topic. If the broker requires SSL for connections, you must include the security-related confluent.topic.* properties as described below.

confluent.license

Confluent issues enterprise license keys to each subscriber. The license key is text that you can copy and paste as the value for confluent.license. A trial license allows using the connector for a 30-day trial period. A developer license allows using the connector indefinitely for single-broker development environments.

If you are a subscriber, please contact Confluent Support for more information.

  • Type: string
  • Default: “”
  • Valid Values: Confluent Platform license
  • Importance: high
confluent.topic.ssl.truststore.location

The location of the trust store file.

  • Type: string
  • Default: null
  • Importance: high
confluent.topic.ssl.truststore.password

The password for the trust store file. If a password is not set access to the truststore is still available, but integrity checking is disabled.

  • Type: password
  • Default: null
  • Importance: high
confluent.topic.ssl.keystore.location

The location of the key store file. This is optional for client and can be used for two-way authentication for client.

  • Type: string
  • Default: null
  • Importance: high
confluent.topic.ssl.keystore.password

The store password for the key store file. This is optional for client and only needed if ssl.keystore.location is configured.

  • Type: password
  • Default: null
  • Importance: high
confluent.topic.ssl.key.password

The password of the private key in the key store file. This is optional for client.

  • Type: password
  • Default: null
  • Importance: high
confluent.topic.security.protocol

Protocol used to communicate with brokers. Valid values are: PLAINTEXT, SSL, SASL_PLAINTEXT, SASL_SSL.

  • Type: string
  • Default: “PLAINTEXT”
  • Importance: medium

License topic configuration

A Confluent enterprise license is stored in the _confluent-command topic. This topic is created by default and contains the license that corresponds to the license key supplied through the confluent.license property.

Note

No public keys are stored in Kafka topics.

The following describes how the default _confluent-command topic is generated under different scenarios:

  • A 30-day trial license is automatically generated for the _confluent command topic if you do not add the confluent.license property or leave this property empty (for example, confluent.license=).
  • Adding a valid license key (for example, confluent.license=<valid-license-key>) adds a valid license in the _confluent-command topic.

Here is an example of the minimal properties for development and testing.

You can change the name of the _confluent-command topic using the confluent.topic property (for instance, if your environment has strict naming conventions). The example below shows this change and the configured Kafka bootstrap server.

confluent.topic=foo_confluent-command
confluent.topic.bootstrap.servers=localhost:9092

The example above shows the minimally required bootstrap server property that you can use for development and testing. For a production environment, you add the normal producer, consumer, and topic configuration properties to the connector properties, prefixed with confluent.topic..

License topic ACLs

The _confluent-command topic contains the license that corresponds to the license key supplied through the confluent.license property. It is created by default. Connectors that access this topic require the following ACLs configured:

  • CREATE and DESCRIBE on the resource cluster, if the connector needs to create the topic.

  • DESCRIBE, READ, and WRITE on the _confluent-command topic.

    Important

    You may also use DESCRIBE and READ without WRITE to restrict access to read-only for license topic ACLs. If a topic exists, the LicenseManager will not try to create the topic.

You can provide access either individually for each principal that will use the license or use a wildcard entry to allow all clients. The following examples show commands that you can use to configure ACLs for the resource cluster and _confluent-command topic.

  1. Set a CREATE and DESCRIBE ACL on the resource cluster:

    kafka-acls --bootstrap-server localhost:9092 --command-config adminclient-configs.conf \
--add --allow-principal User:<principal> \
--operation CREATE --operation DESCRIBE --cluster

  2. Set a DESCRIBE, READ, and WRITE ACL on the _confluent-command topic:

    kafka-acls --bootstrap-server localhost:9092 --command-config adminclient-configs.conf \
--add --allow-principal User:<principal> \
--operation DESCRIBE --operation READ --operation WRITE --topic _confluent-command

Overriding Default Configuration Properties

You can override the replication factor using confluent.topic.replication.factor. For example, when using a Kafka cluster as a destination with less than three brokers (for development and testing) you should set the confluent.topic.replication.factor property to 1.

You can override producer-specific properties by using the confluent.topic.producer. prefix and consumer-specific properties by using the confluent.topic.consumer. prefix.

You can use the defaults or customize the other properties as well. For example, the confluent.topic.client.id property defaults to the name of the connector with -licensing suffix. You can specify the configuration settings for brokers that require SSL or SASL for client connections using this prefix.

You cannot override the cleanup policy of a topic because the topic always has a single partition and is compacted. Also, do not specify serializers and deserializers using this prefix; they are ignored if added.