@namaste/kafka-schema-registry-client

A small utility CLI that allows publishing schemas to the Confluent Kafka Schema Registry. Internally, it uses @namaste/kafka-schema-registry-client to communicate with the server.

Installation

Install the package globally on the machine that you want to register schemas from:

npm i -g @namaste/kafka-schema-registry-cli

or

yarn global add @namaste/kafka-schema-registry-cli

Usage

The CLI is accessible under the register-schemas name. The help is accessible either by calling the program without parameters or environment variables set, or with help option:

register-schemas

or

register-schemas --help

This will print the following output:

Usage: register-schemas [options] <schemasDir>

Options:
  -V, --version            output the version number
  -u, --url <registryUrl>  Confluent schema registry URL
  -k, --key <key>          Confluent schema registry key
  -s, --secret <secret>    Confluent schema registry secret
  -h, --help               output usage information

url, key and secret are required. In place of the required options, you may want to use environment variables:

• SCHEMA_REGISTRY_URL - to set the schema registry URL (-u option)
• SCHEMA_REGISTRY_KEY - to set the schema registry key (-k option)
• SCHEMA_REGISTRY_SECRET - to set the schema registry secret (-s option)

Schemas

To successfuly run the program, you must supply the folder where the file(s) with the schemas you want to publish reside, or put those schemas in the schemas subfolder (the default). The schemas file must be a json file of the following shape:

{
  "[topic-name]": {
    "key": "optional - avro key definition",
    "value": "optional - avro value definition"
  }
}

Example:

{
  "topic-example": {
    "key": {
      "type": "string",
      "namespace": "io.namastetech.schema.example",
      "name": "key",
      "doc": "Unique key"
    },
    "value": {
      "type": "record",
      "namespace": "io.namastetech.schema.example",
      "name": "exampleValue",
      "doc": "A message passed to topic",
      "fields": [
        {
          "name": "id",
          "type": "string",
          "doc": "An ID of the message"
        },
        {
          "name": "message",
          "type": "string",
          "doc": "A string message"
        }
      ]
    }
  }
}

Examples of use

No params

register-schemas

The schemas will be read from ./schemas folder, and schema registry url, key and secret will be read from environment variables.

With folder name

register-schemas my-schemas

The schemas will be read from ./my-schemas folder, and schema registry url, key and secret will be read from environment variables.

With one option provided

register-schemas -u https://myschemaregistryserver.io my-schemas

The schemas will be read from ./my-schemas folder, the schema registry url used will be https://myschemaregistryserver.io, and schema registry key and secret will be read from environment variables.