​Errors and retries

Errors are special branches of a flow where you can define how to react to task failures (e.g. send an email, open a ticket, etc.).

Types of error handling

Two kinds of error handlers can be defined:

• Global: error handling global to a flow that must be at the root of the flow.
• Local: error handling local to a Flowable Task, will handle errors for the flowable task and its children.

Global Error Handler

This flow example has a single Bash task that fails immediately. The global error handler will then be called so the 2nd task will run.

id: errors
namespace: dev

tasks:
  - id: failed
    type: io.kestra.plugin.scripts.shell.Commands
    runner: PROCESS
    commands:
      - exit 1
errors:
  - id: 2nd
    type: io.kestra.core.tasks.log.Log
    message: I'm failing {{task.id}}
    level: INFO

Local Error Handler

In this flow example, the error branch will be used only if a child of the task t2 has an error. If the task t1 failed, the error branch would not be used.

This can be useful to restrict error handling for a specific part of the flow and perform specific tasks like resource cleanup.

id: errors
namespace: dev

tasks:
  - id: parent-seq
    type: io.kestra.core.tasks.flows.Sequential
    tasks:
      - id: t1
        type: io.kestra.core.tasks.debugs.Return
        format: "{{task.id}} > {{taskrun.startDate}}"
      - id: t2
        type: io.kestra.core.tasks.flows.Sequential
        tasks:
          - id: t2-t1
            type: io.kestra.plugin.scripts.shell.Commands
            runner: PROCESS
            commands:
              - 'exit 1'
        errors:
          - id: error-t1
            type: io.kestra.core.tasks.debugs.Return
            format: "Error Trigger ! {{task.id}}"

Retries

Retries provide a way to automatically retry a task when it fails. Check the Retries documentation for more details.