​Inputs

Inputs make your flows more dynamic and reusable.

Instead of hardcoding values in your flow, use inputs to make your workflows more adaptable to change.

Defining inputs

Similar to tasks, inputs is defined as a list of key–value pairs. Each input must have an id and a type. You can also set defaults for each input. Setting default values for an input is always recommended, especially if you want to run your flow on a schedule.

To retrieve an input value, you need to identify the input in an expression. In Kestra, bracket notation {{ }} is used to wrap an expression. For an input, follow this general {{ inputs.input_id }} syntax. In the example below, the input id is set to user, and it's referenced in the task message as {{ inputs.user }}:

id: inputs_demo
namespace: company.team

inputs:
  - id: user
    type: STRING
    defaults: Rick Astley

tasks:
  - id: hello
    type: io.kestra.plugin.core.log.Log
    message: Hey there, {{ inputs.user }}

Try running the above flow with different values for the user input. You can do this by clicking on the Execute button in the UI and then typing the desired value in the menu. For any downstream task, inputs are accessible using expressions.

Here are the most common input types:

Check the inputs documentation for a full list of supported input types.

Parametrize your flow

In our example below, we provide the URL of the API as an input. This allows you to change the URL at execution time without modifying the flow itself.

id: getting_started
namespace: company.team

inputs:
  - id: api_url
    type: STRING
    defaults: https://dummyjson.com/products

tasks:
  - id: api
    type: io.kestra.plugin.core.http.Request
    uri: "{{ inputs.api_url }}"

To learn more about inputs, check out the full inputs documentation.