SFTP Source Connector for Confluent Platform

The SFTP Source connector package for Kafka Connect watches a directory on an SSH File Transfer Protocol (SFTP) server and reads new files as they arrive. Each record in a file is converted using a user-supplied schema or an auto-generated schema.

After the connector reads a file, it moves the file to the directory configured in finished.path.

For an example of how to get Kafka Connect connected to Confluent Cloud, see Connect Self-Managed Kafka Connect to Confluent Cloud.

The following connectors are included in the SFTP Source connector package:

SFTP Source connector features

The SFTP Source connectors include the following features:

At least once delivery

Each connector in the SFTP Source connector package guarantees that records are delivered at least once to the Kafka topic. If the connector restarts, there may be some duplicate records in the Kafka topic.

Supports one task

The connectors in the SFTP Source connector package each support running only one task.

Client-side encryption

This connector supports Client-Side Field Level Encryption (CSFLE) and Client-Side Payload Encryption (CSPE). For more information, see Manage Client-Side Encryption.

File metadata

Starting version 2.3.0, the SFTP Source connector supports exporting file metadata in Kafka headers. The following information is stored in each record’s headers:

  • file.path - The path of the source file on the SFTP server.

  • file.name - The name of the file from which the record was read.

  • file.name.without.extension - The name of the file without the extension.

  • file.last.modified - The last modification time of the file in seconds.

  • file.length - The size of the file in bytes.

  • file.offset - The offset of the record in the file. (N/A for Binary files)

License

You can use this connector for a 30-day trial period without a license key.

After 30 days, you must purchase a connector subscription which includes Confluent enterprise license keys to subscribers, along with enterprise-level support for Confluent Platform and your connectors. If you are a subscriber, you can contact Confluent Support for more information.

For license properties, see Confluent Platform license. For information about the license topic, see License topic configuration.

Limitations

The SFTP Source connector has the following limitations:

  • Currently, the SFTP Source connector reads and moves a file only once while processing files from a specific SFTP directory. If a file with the same name is produced later in the same SFTP directory, the connector does not process it.

  • When the schema.generation.enabled configuration is enabled, the connector offers limited schema detection capabilities and does not support nested or array schemas.

SFTP Source connector configuration properties

For a list of configuration properties for the SFTP Source connectors, see the specific connector documentation.

For an example of how to get Kafka Connect connected to Confluent Cloud, see Connect Self-Managed Kafka Connect to Confluent Cloud.

Install the SFTP Source connector

You can install this connector by using the confluent connect plugin install command, or by manually downloading the ZIP file.

Prerequisites

  • You must install the connector on every machine where Connect will run.

  • If you want to install the connector using Confluent Marketplace, you must install the Confluent Hub Client. This is installed by default with Confluent Enterprise.

  • Kafka Broker: Confluent Platform 3.3.0 or later, or Kafka 0.11.0 or later.

  • Connect: Confluent Platform 4.0.0 or later, or Kafka 1.0.0 or later.

  • Java 1.8.

Install the connector using the Confluent CLI

To install the latest connector version using Confluent Hub Client, navigate to your Confluent Platform installation directory and run the following command:

confluent connect plugin install confluentinc/kafka-connect-sftp:latest

You can install a specific version by replacing latest with a version number as shown in the following example:

confluent connect plugin install confluentinc/kafka-connect-sftp:3.2.0

Install the connector manually

Download and extract the ZIP file for your connector and then follow the manual connector installation instructions.

Quick start

The following steps show the SftpCsvSourceConnector loading a mock CSV file to a Kafka topic named sftp-testing-topic. The other connectors are similar but load from different file types.

  1. Install the connector through the Confluent Hub Client.

    # run from your Confluent Platform installation directory
confluent connect plugin install confluentinc/kafka-connect-sftp:latest

    Tip

    By default, the connector installs the plugin into the share/confluent-hub-components directory and adds the directory to the plugin path. For the plugin path change to take effect, you must restart the Connect worker.

  2. Start Confluent Platform.

    confluent local start

  3. Set up an SFTP data directory for files to process, generate test data locally, and push it to the SFTP server.

    echo $'id,first_name,last_name,email,gender,ip_address,last_login,account_balance,country,favorite_color\n1,Salmon,Baitman,sbaitman0@feedburner.com,Male,120.181.75.98,2015-03-01T06:01:15Z,17462.66,IT,#f09bc0\n2,Debby,Brea,dbrea1@icio.us,Female,153.239.187.49,2018-10-21T12:27:12Z,14693.49,CZ,#73893a' > "csv-sftp-source.csv"

  4. Set up SFTP directories for files with errors and files that finished successfully.

    mkdir error && mkdir finished

  5. Create a sftp.json file with the following contents:

    {
  "name": "CsvSFTP",
  "config": {
    "tasks.max": "1",
    "connector.class": "io.confluent.connect.sftp.SftpCsvSourceConnector",
    "cleanup.policy":"NONE",
    "behavior.on.error":"IGNORE",
    "input.path": "/path/to/data",
    "error.path": "/path/to/error",
    "finished.path": "/path/to/finished",
    "input.file.pattern": "csv-sftp-source.csv",
    "sftp.username":"username",
    "sftp.password":"password",
    "sftp.host":"localhost",
    "sftp.port":"22",
    "kafka.topic": "sftp-testing-topic",
    "csv.first.row.as.header": "true",
    "schema.generation.enabled": "true"
  }
}

  6. Load the SFTP CSV Source connector.

    Caution

    You must include a double dash (--) between the connector name and your flag. For more information, see this post.

    confluent local load CsvSFTP --config sftp.json

    Important

    Don’t use the Confluent CLI in production environments.

  7. Confirm that the connector is in a RUNNING state.

    confluent local status CsvSFTP

  8. Confirm that the messages are being sent to Kafka.

    kafka-avro-console-consumer \
    --bootstrap-server localhost:9092 \
    --property schema.registry.url=http://localhost:8081 \
    --topic sftp-testing-topic \
    --from-beginning | jq '.'

  9. If you have opted for "cleanup.policy":"MOVE", confirm that the source CSV file has been moved to the finished directory.

Examples