Get data from Apache Pulsar

Use the Apache Pulsar source function to get data from an Apache Pulsar topic.

Prerequisites

Before you can use this function, you must create a connection. See Create a DSP connection to Apache Pulsar in the Connect to Data Sources and Destinations with the manual. When configuring this source function, set the connection_id argument to the ID of that connection.

Function output schema

This function outputs records with the schema described in the following table.

Key	Description
key	The key of the record as a string.
value	The payload of the record in bytes.
topic	The name of the Pulsar topic where the record is stored, given as a string.
messageId	The message ID of the record, given as a string.

The following is an example of a typical record from the pulsar function:

{
"key": "my-key",
"value": "aGVsbG8gd29ybGQ=",
"topic": "my-pulsar-topic",
"messageId": 1:24
}

Required arguments

connection_id

Syntax: string

Description: The ID of your Pulsar connection.

Example in Canvas View: my-pulsar-connection

topic

Syntax: string

Description: The name of the Pulsar topic.

Example in Canvas View: my-pulsar-topic

SPL2 example

When working in the SPL View, you can write the function by providing the arguments in this exact order.

| from pulsar("my-connection-id", "my-topic") |...;

Alternatively, you can use named arguments to declare arguments in any order. The following SPL2 example uses named arguments to specify the topic argument before the connection_id argument.

| from pulsar(topic: "my-topic", connection_id: "my-connection-id") |...;

If you want to use a mix of unnamed and named arguments in your functions, you must list all unnamed arguments in the correct order before providing the named arguments.