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Chapter 15. Cassandra Source

Important

The Cassandra Source Kamelet is a Technology Preview feature only. Technology Preview features are not supported with Red Hat production service level agreements (SLAs) and might not be functionally complete. Red Hat does not recommend using them in production.

These features provide early access to upcoming product features, enabling customers to test functionality and provide feedback during the development process. For more information about the support scope of Red Hat Technology Preview features, see https://access.redhat.com/support/offerings/techpreview.

Query a Cassandra cluster table.

15.1. Configuration Options

The following table summarizes the configuration options available for the cassandra-source Kamelet:

Property	Name	Description	Type	Default	Example
connectionHost *	Connection Host	Hostname(s) cassandra server(s). Multiple hosts can be separated by comma.	string		`"localhost"`
connectionPort *	Connection Port	Port number of cassandra server(s)	string		`9042`
keyspace *	Keyspace	Keyspace to use	string		`"customers"`
password *	Password	The password to use for accessing a secured Cassandra Cluster	string
query *	Query	The query to execute against the Cassandra cluster table	string
username *	Username	The username to use for accessing a secured Cassandra Cluster	string
consistencyLevel	Consistency Level	Consistency level to use. The value can be one of ANY, ONE, TWO, THREE, QUORUM, ALL, LOCAL_QUORUM, EACH_QUORUM, SERIAL, LOCAL_SERIAL, LOCAL_ONE	string	`"QUORUM"`
resultStrategy	Result Strategy	The strategy to convert the result set of the query. Possible values are ALL, ONE, LIMIT_10, LIMIT_100…	string	`"ALL"`

Note

Fields marked with an asterisk (*) are mandatory.

15.2. Dependencies

At runtime, the cassandra-source Kamelet relies upon the presence of the following dependencies:

camel:jackson
camel:kamelet
camel:cassandraql

15.3. Usage

This section describes how you can use the cassandra-source.

15.3.1. Knative Source

You can use the cassandra-source Kamelet as a Knative source by binding it to a Knative object.

cassandra-source-binding.yaml

apiVersion: camel.apache.org/v1alpha1
kind: KameletBinding
metadata:
  name: cassandra-source-binding
spec:
  source:
    ref:
      kind: Kamelet
      apiVersion: camel.apache.org/v1alpha1
      name: cassandra-source
    properties:
      connectionHost: "localhost"
      connectionPort: 9042
      keyspace: "customers"
      password: "The Password"
      query: "The Query"
      username: "The Username"
  sink:
    ref:
      kind: Channel
      apiVersion: messaging.knative.dev/v1
      name: mychannel

15.3.1.1. Prerequisite

Make sure you have "Red Hat Integration - Camel K" installed into the OpenShift cluster you’re connected to.

15.3.1.2. Procedure for using the cluster CLI

Save the cassandra-source-binding.yaml file to your local drive, and then edit it as needed for your configuration.
Run the source by using the following command:
```
oc apply -f cassandra-source-binding.yaml
```

15.3.1.3. Procedure for using the Kamel CLI

Configure and run the source by using the following command:

kamel bind cassandra-source -p "source.connectionHost=localhost" -p source.connectionPort=9042 -p "source.keyspace=customers" -p "source.password=The Password" -p "source.query=The Query" -p "source.username=The Username" channel:mychannel

This command creates the KameletBinding in the current namespace on the cluster.

15.3.2. Kafka Source

You can use the cassandra-source Kamelet as a Kafka source by binding it to a Kafka topic.

cassandra-source-binding.yaml

apiVersion: camel.apache.org/v1alpha1
kind: KameletBinding
metadata:
  name: cassandra-source-binding
spec:
  source:
    ref:
      kind: Kamelet
      apiVersion: camel.apache.org/v1alpha1
      name: cassandra-source
    properties:
      connectionHost: "localhost"
      connectionPort: 9042
      keyspace: "customers"
      password: "The Password"
      query: "The Query"
      username: "The Username"
  sink:
    ref:
      kind: KafkaTopic
      apiVersion: kafka.strimzi.io/v1beta1
      name: my-topic

15.3.2.1. Prerequisites

Ensure that you’ve installed the AMQ Streams operator in your OpenShift cluster and created a topic named my-topic in the current namespace. Make also sure you have "Red Hat Integration - Camel K" installed into the OpenShift cluster you’re connected to.

15.3.2.2. Procedure for using the cluster CLI

Save the cassandra-source-binding.yaml file to your local drive, and then edit it as needed for your configuration.
Run the source by using the following command:
```
oc apply -f cassandra-source-binding.yaml
```

15.3.2.3. Procedure for using the Kamel CLI