Red Hat Summit Red Hat SummitSupportConsoleDevelopersStart a trialContact

Chapter 4. Kamelets reference

4.1. Kamelet structure
Copy link

A Kamelet is typically coded in the YAML domain-specific language. The file name prefix is the name of the Kamelet. For example, a Kamelet with the name FTP sink has the filename ftp-sink.kamelet.yaml.

Note that in OpenShift, a Kamelet is a resource that shows the name of the Kamelet (not the filename).

At a high level, a Kamelet resource describes:

  • A metadata section containing the ID of the Kamelet and other information, such as the type of Kamelet (source, sink, or action).
  • A definition (JSON-schema specification) that contains a set of parameters that you can use to configure the Kamelet.
  • An optional types section containing information about input and output expected by the Kamelet.
  • A Camel template in YAML DSL that defines the implementation of the Kamelet.

The following diagram shows an example of a Kamelet and its parts.

Example Kamelet structure 

telegram-text-source.kamelet.yaml
apiVersion: camel.apache.org/v1alpha1
kind: Kamelet
metadata:
  name: telegram-source
1 

  annotations:
2 

    camel.apache.org/catalog.version: "master-SNAPSHOT"
    camel.apache.org/kamelet.icon: "data:image/..."
    camel.apache.org/provider: "Red Hat"
    camel.apache.org/kamelet.group: "Telegram"
  labels:
3 

    camel.apache.org/kamelet.type: "source"
spec:
  definition:
4 

    title: "Telegram Source"
    description: |-
        Receive all messages that people send to your telegram bot.
        To create a bot, contact the @botfather account using the
        Telegram app.
        The source attaches the following headers to the messages:
        - chat-id / ce-chatid: the ID of the chat where the
        message comes from
    required:
        - authorizationToken
    type: object
    properties:
        authorizationToken:
          title: Token
          description: The token to access your bot on Telegram, that you
                   can obtain from the Telegram "Bot Father".
          type: string
          format: password
        x-descriptors:
        - urn:alm:descriptor:com.tectonic.ui:password
  types:
5 

    out:
      mediaType: application/json
  dependencies:
  - "camel:jackson"
  - "camel:kamelet"
  - "camel:telegram"
  template:
6 

    from:
        uri: telegram:bots
        parameters:
            authorizationToken: "{{authorizationToken}}"
        steps:
        - set-header:
          name: chat-id
          simple: "${header[CamelTelegramChatId]}"
        - set-header:
          name: ce-chatid
          simple: "${header[CamelTelegramChatId]}"
        - marshal:
          json: {}
        - to: "kamelet:sink"
Copy to Clipboard Toggle word wrap
  1. The Kamelet ID - Use this ID in Camel K integrations when you want to reference the Kamelet.
  2. Annotations, such as icon, provide display features for the Kamelet.
  3. Labels allow a user to query Kamelets (for example, by kind: "source", "sink", or “action”)
  4. Description of the Kamelet and parameters in JSON-schema specification format.
  5. The media type of the output (can include a schema).
  6. The route template that defines the behavior of the Kamelet.

4.2. Example source Kamelet
Copy link

Here is the content of the example coffee-source Kamelet: 

apiVersion: camel.apache.org/v1alpha1
kind: Kamelet
metadata:
  name: coffee-source
  labels:
    camel.apache.org/kamelet.type: "source"
spec:
  definition:
    title: "Coffee Source"
    description: "Retrieve a random coffee from a catalog of coffees"
    properties:
      period:
        title: Period
        description: The interval between two events in seconds
        type: integer
        default: 1000
  types:
    out:
      mediaType: application/json
  template:
    from:
      uri: timer:tick
      parameters:
        period: "{{period}}"
      steps:
      - to: "https://random-data-api.com/api/coffee/random_coffee"
      - to: "kamelet:sink"
Copy to Clipboard Toggle word wrap
Back to top
Red Hat logoGithubredditYoutubeTwitter

Learn

Try, buy, & sell

Communities

About Red Hat Documentation

We help Red Hat users innovate and achieve their goals with our products and services with content they can trust. Explore our recent updates.

Making open source more inclusive

Red Hat is committed to replacing problematic language in our code, documentation, and web properties. For more details, see the Red Hat Blog.

About Red Hat

We deliver hardened solutions that make it easier for enterprises to work across platforms and environments, from the core datacenter to the network edge.

Theme

© 2025 Red Hat