Solace Sink Connector for Confluent Cloud

The fully-managed Solace Sink connector for Confluent Cloud is used to export data from Apache Kafka® to a Solace PubSub+ Event Broker cluster.

Note

Features

  • At least once delivery: The connector guarantees that records are delivered at least once.

  • Supports multiple tasks: The connector supports running one or more tasks.

  • Input data formats: The connector supports Avro, JSON Schema, Protobuf, JSON (schemaless), String, and Bytes input data formats. Schema Registry must be enabled to use a Schema Registry-based format (for example, Avro, JSON_SR (JSON Schema), or Protobuf). See Schema Registry Enabled Environments for additional information.

For more information and examples to use with the Confluent Cloud API for Connect, see the Confluent Cloud API for Connect Usage Examples section.

Limitations

Be sure to review the following information.

Quick Start

Use this quick start to get up and running with the Confluent Cloud Solace Sink connector. The quick start provides the basics of selecting the connector and configuring it to stream events to Solace.

Prerequisites

  • Kafka cluster credentials. The following lists the different ways you can provide credentials.

    • Enter an existing service account resource ID.

    • Create a Confluent Cloud service account for the connector. Make sure to review the ACL entries required in the service account documentation. Some connectors have specific ACL requirements.

    • Create a Confluent Cloud API key and secret. To create a key and secret, you can use confluent api-key create or you can autogenerate the API key and secret directly in the Cloud Console when setting up the connector.

Using the Confluent Cloud Console

Step 1: Launch your Confluent Cloud cluster

To create and launch a Kafka cluster in Confluent Cloud, see Create a kafka cluster in Confluent Cloud.

Step 2: Add a connector

In the left navigation menu, click Connectors. If you already have connectors in your cluster, click + Add connector.

Step 3: Select your connector

Click the Solace Sink connector card.

Solace Sink Connector Card

Step 4: Enter the connector details

Note

  • Ensure you have all your prerequisites completed.

  • An asterisk ( * ) designates a required entry.

At the Add Solace Sink Connector screen, complete the following:

If you’ve already populated your Kafka topics, select the topics you want to connect from the Topics list.

To create a new topic, click +Add new topic.

  1. Select the way you want to provide Kafka Cluster credentials. You can choose one of the following options:

    • My account: This setting allows your connector to globally access everything that you have access to. With a user account, the connector uses an API key and secret to access the Kafka cluster. This option is not recommended for production.

    • Service account: This setting limits the access for your connector by using a service account. This option is recommended for production.

    • Use an existing API key: This setting allows you to specify an API key and a secret pair. You can use an existing pair or create a new one. This method is not recommended for production environments.

    Note

    Freight clusters support only service accounts for Kafka authentication.

  1. Click Continue.

  1. Enter your Solace connection details:

    • Solace host: IP or hostname and port (optional) of the message broker to connect to. If a port is not specified, the default port number is 55555 when compression is not in use, or 55003 when compression is in use.

    • Solace username: Username to authenticate with Solace.

    • Solace password: Password to authenticate with Solace.

    • Message VPN: Message VPN to use when connecting to the Solace message broker.

    • SSL Keystore: Keystore of SSL-enabled VPN for Solace.

    • SSL Keystore Password: Keystore password for SSL-enabled VPN for Solace.

    • SSL Truststore: Truststore containing server CA certificate for SSL-enabled VPN for Solace.

    • SSL Truststore Password: Truststore password for SSL-enabled VPN for Solace.

    • Validate SSL Certificate: Whether to validate the SSL certificates.

  2. Click Continue.

Note

Configuration properties that are not shown in the Cloud Console use the default values. See Configuration Properties for all property values and descriptions.

  1. Select the Input Kafka record value format (data coming from the Kafka topic): AVRO, JSON_SR (JSON Schema), PROTOBUF, or JSON (schemaless), STRING, or BYTES. Schema Registry must be enabled to use a Schema Registry-based format (for example, AVRO, JSON_SR (JSON Schema), or PROTOBUF). See Schema Registry Enabled Environments for additional information.

  2. For Dynamic Durables, select whether the connector creates queues or topic endpoints (which are used to support durable subscription names) on the message broker. For a queue destination, set this property to true, if the queue doesn’t exist already. If the queue does exist, set the property to false. The connector will fail if you set this property incorrectly.

  3. Enter JMS Destination Name, the name of the JMS destination that messages are written to.

    Show advanced configurations

    • Schema context: Select a schema context to use for this connector, if using a schema-based data format. This property defaults to the Default context, which configures the connector to use the default schema set up for Schema Registry in your Confluent Cloud environment. A schema context allows you to use separate schemas (like schema sub-registries) tied to topics in different Kafka clusters that share the same Schema Registry environment. For example, if you select a non-default context, a Source connector uses only that schema context to register a schema and a Sink connector uses only that schema context to read from. For more information about setting up a schema context, see What are schema contexts and when should you use them?.

    • Compression Level: Sets the ZLIB compression level for messages sent to Solace. The default value is -1, which specifies that the connector uses the JNDI connection compression level. 0 specifies that the connector uses no compression. Levels -1 through 9 enable data compression; where 1 offers the least amount of compression and fastest data throughput, and 9 offers the most compression and slowest data throughput.

    • Client Description: Application description on the message broker for the data connection. Defaults to Kafka Connect.

    • JMS Destination Type: The type of JMS destination. The default value is queue.

    • Forward Kafka Record Key: Whether to convert Kafka record key to a string and forward it on to the JMS Message property JMSCorrelationID. Default value is false.

    • Forward Kafka Record Metadata: Whether to forward Kafka record metadata on the JMS Message properties. Defaults to false.

    • Forward Kafka Record Headers: Whether to add the Kafka record headers to the JMS Message as string properties. Defaults to false.

    • JMS Message Format: The format for JMS message values. The default value is string.

    • Character Encoding: The character encoding to use while writing messages. The default is UTF-8.

    Auto-restart policy

    • Enable Connector Auto-restart: Control the auto-restart behavior of the connector and its task in the event of user-actionable errors. Defaults to true, enabling the connector to automatically restart in case of user-actionable errors. Set this property to false to disable auto-restart for failed connectors. In such cases, you would need to manually restart the connector.

    Consumer configuration

    • Max poll interval(ms): Set the maximum delay between subsequent consume requests to Kafka. Use this property to improve connector performance in cases when the connector cannot send records to the sink system. The default is 300,000 milliseconds (5 minutes).

    • Max poll records: Set the maximum number of records to consume from Kafka in a single request. Use this property to improve connector performance in cases when the connector cannot send records to the sink system. The default is 500 records.

    Transforms

  4. Click Continue.

Based on the number of topic partitions you select, you will be provided with a recommended number of tasks.

  1. To change the number of recommended tasks, enter the number of tasks for the connector to use in the Tasks field.

  2. Click Continue.

  1. Verify the connection details.

  2. Click Launch.

    The status for the connector should go from Provisioning to Running.

Step 5: Check the results in Solace

Verify that messages are streaming to the Solace event broker.

For more information and examples to use with the Confluent Cloud API for Connect, see the Confluent Cloud API for Connect Usage Examples section.

Tip

When you launch a connector, a Dead Letter Queue topic is automatically created. See View Connector Dead Letter Queue Errors in Confluent Cloud for details.

Using the Confluent CLI

Complete the following steps to set up and run the connector using the Confluent CLI.

Note

Make sure you have all your prerequisites completed.

Step 1: List the available connectors

Enter the following command to list available connectors:

confluent connect plugin list

Step 2: List the connector configuration properties

Enter the following command to show the connector configuration properties:

confluent connect plugin describe <connector-plugin-name>

The command output shows the required and optional configuration properties.

Step 3: Create the connector configuration file

Create a JSON file that contains the connector configuration properties. The following example shows required connector properties. See Configuration Properties for additional configuration property values and descriptions.

{
  "name": "SolaceConnector_0",
  "config": {
    "topics": "pageviews",
    "connector.class": "SolaceSink",
    "name": "SolaceSinkConnector_0",
    "input.data.format": "STRING",
    "kafka.auth.mode": "KAFKA_API_KEY",
    "kafka.api.key": "<my-kafka-api-key>",
    "kafka.api.secret": "<my-kafka-api-secret>",
    "solace.host": "tcps://mr83451.messaging.solace.cloud:55443",
    "solace.username": "<username>",
    "solace.password": "<password>",
    "solace.dynamic.durables": "true",
    "jms.destination.name": "<destination-name>",
    "tasks.max": "1"
  }
}

Note the following property definitions:

  • "name": Sets a name for your new connector.

  • "connector.class": Identifies the connector plugin name.

  • "topics": Identifies the topic name or a comma-separated list of topic names.

  • "input.data.format": Sets the input Kafka record value format (data coming from the Kafka topic). Valid entries are AVRO, JSON_SR, PROTOBUF, STRING, JSON (schemaless), or BYTES. You must have Schema Registry configured if using a schema-based message format (for example, Avro, JSON_SR (JSON Schema), or Protobuf).

  • "kafka.auth.mode": Identifies the connector authentication mode you want to use. There are two options: SERVICE_ACCOUNT or KAFKA_API_KEY (the default). To use an API key and secret, specify the configuration properties kafka.api.key and kafka.api.secret, as shown in the example configuration (above). To use a service account, specify the Resource ID in the property kafka.service.account.id=<service-account-resource-ID>. To list the available service account resource IDs, use the following command:

    confluent iam service-account list

    For example:

    confluent iam service-account list

   Id     | Resource ID |       Name        |    Description
+---------+-------------+-------------------+-------------------
   123456 | sa-l1r23m   | sa-1              | Service account 1
   789101 | sa-l4d56p   | sa-2              | Service account 2

  • "solace.<...>": Enter the connection details. solace.host specifies the IP or hostname and port (optional) of the message broker to connect to. For a non-SSL host entry, if a port is not specified and compression is not in use, the default port number used is 55555. When compression is used, the default port is 55003. The default port for SSL connections (with or without compression) is 55443. An SSL host entry would look similar to the following example (valid schemes: tcp, tcps, smf, or smfs). For additional information, see Data Connection Properties.

  • "solace.dynamic.durables": Whether queues or topic endpoints (used to support durable subscription names) are created on the message broker. For a queue destination, set this property to true, if the queue doesn’t exist already. If the queue does exist, set the property to false. The connector will fail if you set this property incorrectly.

  • "jms.destination.name": Enter the queue or topic name to send messages to.

  • "tasks.max": Maximum tasks for the connector to use. More tasks may improve performance.

Single Message Transforms: See the Single Message Transforms (SMT) documentation for details about adding SMTs using the CLI. See Unsupported transformations for a list of SMTs that are not supported with this connector.

See Configuration Properties for all property values and descriptions.

Step 4: Load the configuration file and create the connector

Enter the following command to load the configuration and start the connector:

confluent connect cluster create --config-file <file-name>.json

For example:

confluent connect cluster create --config-file solace-sink-config.json

Example output:

Created connector SolaceSinkConnector_0 lcc-ix4dl

Step 5: Check the connector status

Enter the following command to check the connector status:

confluent connect cluster list

Example output:

ID          |       Name             | Status  | Type
+-----------+------------------------+---------+------+
lcc-ix4dl   | SolaceSinkConnector_0  | RUNNING | sink

Step 6: Check the results in Solace.

Verify that messages are streaming to the Solace event broker.

For more information and examples to use with the Confluent Cloud API for Connect, see the Confluent Cloud API for Connect Usage Examples section.

Tip

When you launch a connector, a Dead Letter Queue topic is automatically created. See View Connector Dead Letter Queue Errors in Confluent Cloud for details.

Configuration Properties

Use the following configuration properties with the fully-managed connector. For self-managed connector property definitions and other details, see the connector docs in Self-managed connectors for Confluent Platform.

How should we connect to your data?

name

Sets a name for your connector.

  • Type: string

  • Valid Values: A string at most 64 characters long

  • Importance: high

Which topics do you want to get data from?

topics.regex

A regular expression that matches the names of the topics to consume from. This is useful when you want to consume from multiple topics that match a certain pattern without having to list them all individually.

  • Type: string

  • Importance: low

topics

Identifies the topic name or a comma-separated list of topic names.

  • Type: list

  • Importance: high

Schema Config

schema.context.name

Add a schema context name. A schema context represents an independent scope in Schema Registry. It is a separate sub-schema tied to topics in different Kafka clusters that share the same Schema Registry instance. If not used, the connector uses the default schema configured for Schema Registry in your Confluent Cloud environment.

  • Type: string

  • Default: default

  • Importance: medium

Input messages

input.data.format

Sets the input Kafka record value format. Valid entries are AVRO, JSON_SR, PROTOBUF, JSON, STRING or BYTES. Note that you need to have Confluent Cloud Schema Registry configured if using a schema-based message format like AVRO, JSON_SR, and PROTOBUF.

  • Type: string

  • Importance: high

Kafka Cluster credentials

kafka.auth.mode

Kafka Authentication mode. It can be one of KAFKA_API_KEY or SERVICE_ACCOUNT. It defaults to KAFKA_API_KEY mode.

  • Type: string

  • Default: KAFKA_API_KEY

  • Valid Values: KAFKA_API_KEY, SERVICE_ACCOUNT

  • Importance: high

kafka.api.key

Kafka API Key. Required when kafka.auth.mode==KAFKA_API_KEY.

  • Type: password

  • Importance: high

kafka.service.account.id

The Service Account that will be used to generate the API keys to communicate with Kafka Cluster.

  • Type: string

  • Importance: high

kafka.api.secret

Secret associated with Kafka API key. Required when kafka.auth.mode==KAFKA_API_KEY.

  • Type: password

  • Importance: high

How should we connect to your Solace cluster?

solace.host

IP or hostname and port (optional) of the message broker to connect to. If a port is not specified, the default port number is 55555 when compression is not in use, or 55003 when compression is in use.

  • Type: string

  • Importance: high

solace.username

Username to authenticate with Solace.

  • Type: string

  • Importance: high

solace.password

Password to authenticate with Solace.

  • Type: password

  • Importance: high

solace.vpn

Message VPN to use when connecting to the Solace message broker.

  • Type: string

  • Importance: medium

Connection details

solace.compression.level

ZLIB compression level for messages written to Solace. Valid values for the compression level are -1 through 9. -1 means use the JNDI connection’s compression level. 0 means use no compression. 1 through 9 enables data compression (where 1 offers the least amount of compression and fastest data throughput, and 9 offers the most compression and slowest data throughput)

  • Type: int

  • Default: -1

  • Valid Values: [-1,…,9]

  • Importance: medium

solace.dynamic.durables

Whether queues or topic endpoints (which are used to support durable subscription names), are to be created on the message broker. In case of queue destination, set this property to true if the queue doesn’t exist already, false otherwise. Setting it incorrectly will fail the connector.

  • Type: boolean

  • Importance: low

solace.client.description

Application description on the message broker for the data connection.

  • Type: string

  • Default: Kafka Connect

  • Importance: low

Solace secure connection

solace.ssl.keystore.file

Keystore of SSL-enabled VPN for Solace.

  • Type: password

  • Default: [hidden]

  • Importance: medium

solace.ssl.keystore.password

Keystore password for SSL-enabled VPN for Solace.

  • Type: password

  • Importance: medium

solace.ssl.truststore.file

Truststore containing server CA certificate for SSL-enabled VPN for Solace.

  • Type: password

  • Default: [hidden]

  • Importance: medium

solace.ssl.truststore.password

Truststore password for SSL-enabled VPN for Solace.

  • Type: password

  • Importance: medium

solace.ssl.validate.certificate

Whether to validate the SSL certificates.

  • Type: boolean

  • Default: true

  • Importance: medium

JMS details

jms.destination.name

The name of the JMS destination that messages are written to.

  • Type: string

  • Importance: high

jms.destination.type

The type of JMS destination.

  • Type: string

  • Default: queue

  • Importance: high

jms.forward.kafka.key

Convert the Kafka record key to a string and forward it on the JMS Message property JMSCorrelationID.

  • Type: boolean

  • Default: false

  • Importance: low

jms.forward.kafka.metadata

Forward the Kafka record metadata on the JMS Message properties. This includes the record topic, partition, and offset.

  • Type: boolean

  • Default: false

  • Importance: low

jms.forward.kafka.headers

Add the Kafka record headers to the JMS Message as string properties.

  • Type: boolean

  • Default: false

  • Importance: low

JMS formatter

jms.message.format

The format of JMS message values.

  • Type: string

  • Default: string

  • Importance: high

character.encoding

The character encoding to use while writing the message.

  • Type: string

  • Default: UTF-8

  • Importance: low

Consumer configuration

max.poll.interval.ms

The maximum delay between subsequent consume requests to Kafka. This configuration property may be used to improve the performance of the connector, if the connector cannot send records to the sink system. Defaults to 300000 milliseconds (5 minutes).

  • Type: long

  • Default: 300000 (5 minutes)

  • Valid Values: [60000,…,1800000] for non-dedicated clusters and [60000,…] for dedicated clusters

  • Importance: low

max.poll.records

The maximum number of records to consume from Kafka in a single request. This configuration property may be used to improve the performance of the connector, if the connector cannot send records to the sink system. Defaults to 500 records.

  • Type: long

  • Default: 500

  • Valid Values: [1,…,500] for non-dedicated clusters and [1,…] for dedicated clusters

  • Importance: low

Number of tasks for this connector

tasks.max

Maximum number of tasks for the connector.

  • Type: int

  • Valid Values: [1,…]

  • Importance: high

Auto-restart policy

auto.restart.on.user.error

Enable connector to automatically restart on user-actionable errors.

  • Type: boolean

  • Default: true

  • Importance: medium

Additional Configs

consumer.override.auto.offset.reset

Defines the behavior of the consumer when there is no committed position (which occurs when the group is first initialized) or when an offset is out of range. You can choose either to reset the position to the “earliest” offset (the default) or the “latest” offset. You can also select “none” if you would rather set the initial offset yourself and you are willing to handle out of range errors manually. More details: https://docs.confluent.io/platform/current/installation/configuration/consumer-configs.html#auto-offset-reset

  • Type: string

  • Importance: low

consumer.override.isolation.level

Controls how to read messages written transactionally. If set to read_committed, consumer.poll() will only return transactional messages which have been committed. If set to read_uncommitted (the default), consumer.poll() will return all messages, even transactional messages which have been aborted. Non-transactional messages will be returned unconditionally in either mode. More details: https://docs.confluent.io/platform/current/installation/configuration/consumer-configs.html#isolation-level

  • Type: string

  • Importance: low

header.converter

The converter class for the headers. This is used to serialize and deserialize the headers of the messages.

  • Type: string

  • Importance: low

value.converter.allow.optional.map.keys

Allow optional string map key when converting from Connect Schema to Avro Schema. Applicable for Avro Converters.

  • Type: boolean

  • Importance: low

value.converter.auto.register.schemas

Specify if the Serializer should attempt to register the Schema.

  • Type: boolean

  • Importance: low

value.converter.connect.meta.data

Allow the Connect converter to add its metadata to the output schema. Applicable for Avro Converters.

  • Type: boolean

  • Importance: low

value.converter.enhanced.avro.schema.support

Enable enhanced schema support to preserve package information and Enums. Applicable for Avro Converters.

  • Type: boolean

  • Importance: low

value.converter.enhanced.protobuf.schema.support

Enable enhanced schema support to preserve package information. Applicable for Protobuf Converters.

  • Type: boolean

  • Importance: low

value.converter.flatten.unions

Whether to flatten unions (oneofs). Applicable for Protobuf Converters.

  • Type: boolean

  • Importance: low

value.converter.generate.index.for.unions

Whether to generate an index suffix for unions. Applicable for Protobuf Converters.

  • Type: boolean

  • Importance: low

value.converter.generate.struct.for.nulls

Whether to generate a struct variable for null values. Applicable for Protobuf Converters.

  • Type: boolean

  • Importance: low

value.converter.int.for.enums

Whether to represent enums as integers. Applicable for Protobuf Converters.

  • Type: boolean

  • Importance: low

value.converter.latest.compatibility.strict

Verify latest subject version is backward compatible when use.latest.version is true.

  • Type: boolean

  • Importance: low

value.converter.object.additional.properties

Whether to allow additional properties for object schemas. Applicable for JSON_SR Converters.

  • Type: boolean

  • Importance: low

value.converter.optional.for.nullables

Whether nullable fields should be specified with an optional label. Applicable for Protobuf Converters.

  • Type: boolean

  • Importance: low

value.converter.optional.for.proto2

Whether proto2 optionals are supported. Applicable for Protobuf Converters.

  • Type: boolean

  • Importance: low

value.converter.use.latest.version

Use latest version of schema in subject for serialization when auto.register.schemas is false.

  • Type: boolean

  • Importance: low

value.converter.use.optional.for.nonrequired

Whether to set non-required properties to be optional. Applicable for JSON_SR Converters.

  • Type: boolean

  • Importance: low

value.converter.wrapper.for.nullables

Whether nullable fields should use primitive wrapper messages. Applicable for Protobuf Converters.

  • Type: boolean

  • Importance: low

value.converter.wrapper.for.raw.primitives

Whether a wrapper message should be interpreted as a raw primitive at root level. Applicable for Protobuf Converters.

  • Type: boolean

  • Importance: low

key.converter.key.subject.name.strategy

How to construct the subject name for key schema registration.

  • Type: string

  • Default: TopicNameStrategy

  • Importance: low

value.converter.decimal.format

Specify the JSON/JSON_SR serialization format for Connect DECIMAL logical type values with two allowed literals:

BASE64 to serialize DECIMAL logical types as base64 encoded binary data and

NUMERIC to serialize Connect DECIMAL logical type values in JSON/JSON_SR as a number representing the decimal value.

  • Type: string

  • Default: BASE64

  • Importance: low

value.converter.flatten.singleton.unions

Whether to flatten singleton unions. Applicable for Avro and JSON_SR Converters.

  • Type: boolean

  • Default: false

  • Importance: low

value.converter.reference.subject.name.strategy

Set the subject reference name strategy for value. Valid entries are DefaultReferenceSubjectNameStrategy or QualifiedReferenceSubjectNameStrategy. Note that the subject reference name strategy can be selected only for PROTOBUF format with the default strategy being DefaultReferenceSubjectNameStrategy.

  • Type: string

  • Default: DefaultReferenceSubjectNameStrategy

  • Importance: low

value.converter.value.subject.name.strategy

Determines how to construct the subject name under which the value schema is registered with Schema Registry.

  • Type: string

  • Default: TopicNameStrategy

  • Importance: low

Egress allowlist

connector.egress.whitelist

  • Type: string

  • Default: “”

  • Importance: high

Next Steps

For an example that shows fully-managed Confluent Cloud connectors in action with Confluent Cloud for Apache Flink, see the Cloud ETL Demo. This example also shows how to use Confluent CLI to manage your resources in Confluent Cloud.

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