FlowFlow
FlowCertified

Trigger a flow in response to a state change in one or more other flows.

Trigger a flow in response to a state change in one or more other flows.

You can trigger a flow as soon as another flow ends. This allows you to add implicit dependencies between multiple flows, which can often be managed by different teams.

A flow trigger must have preconditions which filter on other flow executions. It can also have standard trigger conditions. Neither condition type can use Pebble templating expressions; they must be declaratively defined. Upstream execution outputs will be available in a trigger.outputs variable.

yaml
type: "io.kestra.plugin.core.trigger.Flow"
  1. Trigger the transform flow after the extract flow finishes successfully. The extract flow generates a date output that is passed to the transform flow as an input.
yaml
id: extract
namespace: company.team

tasks: 
  - id: final_date
    type: io.kestra.plugin.core.debug.Return
    format: "{{ execution.startDate | dateAdd(-2, 'DAYS') | date('yyyy-MM-dd') }}"

outputs: 
  - id: date
    type: STRING
    value: "{{ outputs.final_date.value }}"

The transform flow is triggered after the extract flow finishes successfully.

yaml
id: transform
namespace: company.team

inputs:
  - id: date
    type: STRING
    defaults: "2025-01-01"

variables:
  result: |
    Ingestion done in {{ trigger.executionId }}.
    Now transforming data up to {{ inputs.date }}

tasks:
  - id: run_transform
    type: io.kestra.plugin.core.debug.Return
    format: "{{ render(vars.result) }}"

  - id: log
    type: io.kestra.plugin.core.log.Log
    message: "{{ render(vars.result) }}"

triggers:
  - id: run_after_extract
    type: io.kestra.plugin.core.trigger.Flow
    inputs:
      date: "{{ trigger.outputs.date }}"
    preconditions:
      id: flows
      flows:
        - namespace: company.team
          flowId: extract
          states: [SUCCESS]

  1. Trigger the silver_layer flow once the bronze_layer flow finishes successfully by 9 AM.
yaml
id: bronze_layer
namespace: company.team

tasks: 
  - id: raw_data
    type: io.kestra.plugin.core.log.Log
    message: Ingesting raw data
yaml
id: silver_layer
namespace: company.team

tasks:
  - id: transform_data
    type: io.kestra.plugin.core.log.Log
    message: deduplication, cleaning, and minor aggregations

triggers:
  - id: flow_trigger
    type: io.kestra.plugin.core.trigger.Flow
    preconditions:
      id: bronze_layer
      timeWindow:
        type: DAILY_TIME_DEADLINE
        deadline: "09:00:00"
      flows:
        - namespace: company.team
          flowId: bronze_layer
          states: [SUCCESS]

  1. Create a System Flow to send a Slack alert on any failure or warning state within the company namespace. This example uses the Slack webhook secret to notify the #general channel about the failed flow.
yaml
id: alert
namespace: system

tasks:
  - id: send_alert
    type: io.kestra.plugin.notifications.slack.SlackExecution
    url: "{{secret('SLACK_WEBHOOK')}}" # format: https://hooks.slack.com/services/xzy/xyz/xyz
    channel: "#general"
    executionId: "{{trigger.executionId}}"

triggers:
  - id: alert_on_failure
    type: io.kestra.plugin.core.trigger.Flow
    states:
      - FAILED
      - WARNING
    preconditions:
      id: company_namespace
      where:
        - id: company
          filters:
            - field: NAMESPACE
              type: STARTS_WITH
              value: company

  1. Create a System Flow to send a Sentry issue on any failure or warning state within the company.payroll namespace. This example uses the Sentry Execution task and a Flow trigger with conditions.
yaml
id: sentry_execution_example
namespace: company.team

tasks:
- id: send_alert
  type: io.kestra.plugin.notifications.sentry.SentryExecution
  executionId: "{{ trigger.executionId }}"
  transaction: "/execution/id/{{ trigger.executionId }}"
  dsn: "{{ secret('SENTRY_DSN') }}"
  level: ERROR

triggers:
- id: failed_prod_workflows
  type: io.kestra.plugin.core.trigger.Flow
  conditions:
  - type: io.kestra.plugin.core.condition.ExecutionStatus
    in:
      - FAILED
      - WARNING
  - type: io.kestra.plugin.core.condition.ExecutionNamespace
    namespace: company.payroll
    prefix: false

  1. Chain two different flows (flow_a and flow_b) and trigger the second only after the first completes successfully with matching labels. Note that this example is two separate flows.
yaml
id: flow_a
namespace: company.team
labels:
  type: orchestration
tasks:
  - id: hello
    type: io.kestra.plugin.core.log.Log
    message: Hello World!
---
id: flow_b
namespace: company.team

tasks:
  - id: hello
    type: io.kestra.plugin.core.log.Log
    message: Hello World!

triggers:
  - id: on_completion
    type: io.kestra.plugin.core.trigger.Flow
    states: [SUCCESS]
    labels:
      type: orchestration
    preconditions:
      id: flow_a
        id: flow_a
        where:
          - id: label_filter
            filters:
              - field: EXPRESSION
                type: IS_TRUE
                value: "{{ labels.type == 'orchestration' }}
Properties
Defaultfalse

Specifies whether a trigger is allowed to start a new execution even if a previous run is still in progress.

List of conditions in order to limit the flow trigger.

Definitions
type*Requiredobject
afterstring
Formatdate-time

The date to test must be after this one.

beforestring
Formatdate-time

The date to test must be before this one.

Must be a valid ISO 8601 datetime with the zone identifier (use 'Z' for the default zone identifier).

datestring
Default{{ trigger.date }}
dayOfWeek*Requiredstring
Possible Values
MONDAYTUESDAYWEDNESDAYTHURSDAYFRIDAYSATURDAYSUNDAY
type*Requiredobject
datestring
Default{{ trigger.date }}
dayInMonth*Requiredstring
Possible Values
FIRSTLASTSECONDTHIRDFOURTH

Are you looking for the first or the last day in the month?

dayOfWeek*Requiredstring
Possible Values
MONDAYTUESDAYWEDNESDAYTHURSDAYFRIDAYSATURDAYSUNDAY

The day of week.

type*Requiredobject
datestring
Default{{ trigger.date }}
flowId*Requiredstring
namespace*Requiredstring
type*Requiredobject
labels*Requiredarrayobject

List of labels to match in the execution.

type*Requiredobject
namespace*Requiredstring

String against which to match the execution namespace depending on the provided comparison.

type*Requiredobject
comparisonstring
Possible Values
EQUALSPREFIXSUFFIX

Comparison to use when checking if namespace matches. If not provided, it will use EQUALS by default.

prefixbooleanstring
Defaultfalse

Whether to look at the flow namespace by prefix. Shortcut for comparison: PREFIX.

Only used when comparison is not set

expression*Requiredbooleanstring
type*Requiredobject
type*Requiredobject
inarray
SubTypestring
Possible Values
CREATEDSUBMITTEDRUNNINGPAUSEDRESTARTEDKILLINGSUCCESSWARNINGFAILEDKILLEDCANCELLEDQUEUEDRETRYINGRETRIEDSKIPPEDBREAKPOINTRESUBMITTED
notInarray
SubTypestring
Possible Values
CREATEDSUBMITTEDRUNNINGPAUSEDRESTARTEDKILLINGSUCCESSWARNINGFAILEDKILLEDCANCELLEDQUEUEDRETRYINGRETRIEDSKIPPEDBREAKPOINTRESUBMITTED
expression*Requiredstring
type*Requiredobject
flowId*Requiredstring

The flow id.

namespace*Requiredstring

The namespace of the flow.

type*Requiredobject
namespace*Requiredstring

The namespace of the flow or the prefix if prefix is true.

type*Requiredobject
prefixboolean
Defaultfalse

If we must look at the flow namespace by prefix (checked using startsWith). The prefix is case sensitive.

type*Requiredobject
inarray
SubTypestring
Possible Values
CREATEDSUBMITTEDRUNNINGPAUSEDRESTARTEDKILLINGSUCCESSWARNINGFAILEDKILLEDCANCELLEDQUEUEDRETRYINGRETRIEDSKIPPEDBREAKPOINTRESUBMITTED

List of states that are authorized.

notInarray
SubTypestring
Possible Values
CREATEDSUBMITTEDRUNNINGPAUSEDRESTARTEDKILLINGSUCCESSWARNINGFAILEDKILLEDCANCELLEDQUEUEDRETRYINGRETRIEDSKIPPEDBREAKPOINTRESUBMITTED

List of states that aren't authorized.

conditions*Requiredobject

The list of preconditions to wait for

The key must be unique for a trigger because it will be used to store the previous evaluation result.

id*Requiredstring
Validation RegExp^[a-zA-Z0-9][a-zA-Z0-9_-]*
Min length1

A unique id for the condition

type*Requiredobject
resetOnSuccessboolean
Defaulttrue

Whether to reset the evaluation results of SLA conditions after a first successful evaluation within the given time period.

By default, after a successful evaluation of the set of SLA conditions, the evaluation result is reset, so, the same set of conditions needs to be successfully evaluated again in the same time period to trigger a new execution. This means that to create multiple executions, the same set of conditions needs to be evaluated to true multiple times. You can disable this by setting this property to false so that, within the same period, each time one of the conditions is satisfied again after a successful evaluation, it will trigger a new execution.

timeWindow
Default{ "type": "DURATION_WINDOW" }

Define the time period (or window) for evaluating preconditions.

You can set the type of sla to one of the following values:

  1. DURATION_WINDOW: this is the default type. It uses a start time (windowAdvance) and end time (window) that are moving forward to the next interval whenever the evaluation time reaches the end time, based on the defined duration window. For example, with a 1-day window (the default option: window: PT1D), the SLA conditions are always evaluated during 24h starting at midnight (i.e. at time 00: 00: 00) each day. If you set windowAdvance: PT6H, the window will start at 6 AM each day. If you set windowAdvance: PT6H and you also override the window property to PT6H, the window will start at 6 AM and last for 6 hours — as a result, Kestra will check the SLA conditions during the following time periods: 06: 00 to 12: 00, 12: 00 to 18: 00, 18: 00 to 00: 00, and 00: 00 to 06: 00, and so on.
  2. SLIDING_WINDOW: this option also evaluates SLA conditions over a fixed time window, but it always goes backward from the current time. For example, a sliding window of 1 hour (window: PT1H) will evaluate executions for the past hour (so between now and one hour before now). It uses a default window of 1 day.
  3. DAILY_TIME_DEADLINE: this option declares that some SLA conditions should be met "before a specific time in a day". With the string property deadline, you can configure a daily cutoff for checking conditions. For example, deadline: "09: 00: 00" means that the defined SLA conditions should be met from midnight until 9 AM each day; otherwise, the flow will not be triggered.
  4. DAILY_TIME_WINDOW: this option declares that some SLA conditions should be met "within a given time range in a day". For example, a window from startTime: "06: 00: 00" to endTime: "09: 00: 00" evaluates executions within that interval each day. This option is particularly useful for declarative definition of freshness conditions when building data pipelines. For example, if you only need one successful execution within a given time range to guarantee that some data has been successfully refreshed in order for you to proceed with the next steps of your pipeline, this option can be more useful than a strict DAG-based approach. Usually, each failure in your flow would block the entire pipeline, whereas with this option, you can proceed with the next steps of the pipeline as soon as the data is successfully refreshed at least once within the given time range.
deadlinestring
Formatpartial-time
endTimestring
Formatpartial-time
startTimestring
Formatpartial-time
typestring
DefaultDURATION_WINDOW
Possible Values
DAILY_TIME_DEADLINEDAILY_TIME_WINDOWDURATION_WINDOWSLIDING_WINDOW
windowstring
Formatduration
windowAdvancestring
Formatduration
windowDeprecatedstring
Formatduration

Deprecated, use timeWindow.window instead.

windowAdvanceDeprecatedstring
Formatduration

Deprecated, use timeWindow.windowAdvance instead.

conditions*Required
Min items1

The list of conditions to exclude.

If any condition is true, it will prevent the event's execution.

type*Requiredobject
conditions*Required
Min items1

The list of conditions to validate.

If any condition is true, it will allow the event's execution.

type*Requiredobject
type*Requiredobject
countrystring

ISO 3166-1 alpha-2 country code. If not set, it uses the country code from the default locale.

datestring
Default{{ trigger.date}}
subDivisionstring

ISO 3166-2 country subdivision (e.g., provinces and states) code.

It uses the Jollyday library for public holiday calendar that supports more than 70 countries.

type*Requiredobject
afterstring
Formattime

The time to test must be after this one.

beforestring
Formattime

The time to test must be before this one.

Must be a valid ISO 8601 time with offset.

datestring
Default{{ trigger.date }}

The time to test.

Can be any variable or any valid ISO 8601 time. By default, it will use the trigger date.

type*Requiredobject
datestring
Default{{ trigger.date }}

The date to test.

Can be any variable or any valid ISO 8601 datetime. By default, it will use the trigger date.

Pass upstream flow's outputs to inputs of the current flow.

The inputs property passes data objects or a file to the downstream flow as long as those outputs are defined on the flow-level in the upstream flow.

Preconditions on upstream flow executions

Express preconditions to be met, on a time window, for the flow trigger to be evaluated.

Definitions
id*Requiredstring
Validation RegExp^[a-zA-Z0-9][a-zA-Z0-9_-]*
Min length1

A unique id for the preconditions

flowsarray

A list of preconditions to meet, in the form of upstream flows

namespace*Requiredstring

The namespace of the flow

flowIdstring

The flow ID

labelsobject

A key/value map of labels

statesarray
SubTypestring
Possible Values
CREATEDSUBMITTEDRUNNINGPAUSEDRESTARTEDKILLINGSUCCESSWARNINGFAILEDKILLEDCANCELLEDQUEUEDRETRYINGRETRIEDSKIPPEDBREAKPOINTRESUBMITTED

The execution states

resetOnSuccessboolean
Defaulttrue

Whether to reset the evaluation results of preconditions after a first successful evaluation within the given time window

By default, after a successful evaluation of the set of preconditions, the evaluation result is reset. This means the same set of conditions needs to be successfully evaluated again within the same time window to trigger a new execution. In this setup, to create multiple executions, the same set of conditions must be evaluated to true multiple times within the defined window. You can disable this by setting this property to false, so that within the same window, each time one of the conditions is satisfied again after a successful evaluation, it will trigger a new execution.

timeWindow
Default{ "type": "DURATION_WINDOW" }

Define the time window for evaluating preconditions.

You can set the type of timeWindow to one of the following values:

  1. DURATION_WINDOW: this is the default type. It uses a start time (windowAdvance) and end time (window) that advance to the next interval whenever the evaluation time reaches the end time, based on the defined duration window. For example, with a 1-day window (the default option: window: PT1D), the preconditions are evaluated during a 24-hour period starting at midnight (i.e., at "00: 00: 00+00: 00") each day. If you set windowAdvance: PT6H, the window will start at 6 AM each day. If you set windowAdvance: PT6H and also override the window property to PT6H, the window will start at 6 AM and last for 6 hours. In this configuration, the preconditions will be evaluated during the following intervals: 06: 00 to 12: 00, 12: 00 to 18: 00, 18: 00 to 00: 00, and 00: 00 to 06: 00.
  2. SLIDING_WINDOW: this option evaluates preconditions over a fixed time window but always goes backward from the current time. For example, a sliding window of 1 hour (window: PT1H) evaluates executions within the past hour (from one hour ago up to now). It uses a default window of 1 day.
  3. DAILY_TIME_DEADLINE: this option declares that preconditions should be met "before a specific time in a day." Using the string property deadline, you can configure a daily cutoff for evaluating preconditions. For example, deadline: "09: 00: 00" specifies that preconditions must be met from midnight until 9 AM UTC time each day; otherwise, the flow will not be triggered.
  4. DAILY_TIME_WINDOW: this option declares that preconditions should be met "within a specific time range in a day". For example, a window from startTime: "06: 00: 00" to endTime: "09: 00: 00" evaluates executions within that interval each day. This option is particularly useful for defining freshness conditions declaratively when building data pipelines that span multiple teams and namespaces. Normally, a failure in any task in your flow will block the entire pipeline, but with this decoupled flow trigger alternative, you can proceed as soon as the data is successfully refreshed within the specified time window.
deadlinestring
Formatpartial-time

SLA daily deadline

Use it only for DAILY_TIME_DEADLINE SLA.

endTimestring
Formatpartial-time

SLA daily end time

startTimestring
Formatpartial-time

SLA daily start time

Use it only for DAILY_TIME_WINDOW SLA.

typestring
DefaultDURATION_WINDOW
Possible Values
DAILY_TIME_DEADLINEDAILY_TIME_WINDOWDURATION_WINDOWSLIDING_WINDOW

The type of the SLA

The default SLA is a sliding window (DURATION_WINDOW) with a window of 24 hours.

windowstring
Formatduration

The duration of the window

Use it only for DURATION_WINDOW or SLIDING_WINDOW SLA. See ISO_8601 Durations for more information of available duration value. The start of the window is always based on midnight except if you set windowAdvance parameter. Eg if you have a 10 minutes (PT10M) window, the first window will be 00: 00 to 00: 10 and a new window will be started each 10 minutes

windowAdvancestring
Formatduration

The window advance duration

Use it only for DURATION_WINDOW SLA. Allow to specify the start time of the window Eg: you want a window of 6 hours (window=PT6H), by default the check will be done between: 00: 00 and 06: 00, 06: 00 and 12: 00, 12: 00 and 18: 00, and 18: 00 and 00: 00. If you want to check the window between 03: 00 and 09: 00, 09: 00 and 15: 00, 15: 00 and 21: 00, and 21: 00 and 3: 00, you will have to shift the window of 3 hours by settings windowAdvance: PT3H

wherearray

A list of preconditions to meet, in the form of execution filters

filters*Requiredarray
Min items1

The list of filters

field*Requiredstring
Possible Values
FLOW_IDNAMESPACESTATEEXPRESSION

The field which will be filtered

type*Requiredstring
Possible Values
EQUAL_TONOT_EQUAL_TOINNOT_INIS_TRUEIS_FALSEIS_NULLIS_NOT_NULLSTARTS_WITHENDS_WITHREGEXCONTAINS

The type of filter

Can be set to one of the following: EQUAL_TO, NOT_EQUAL_TO, IS_NULL, IS_NOT_NULL, IS_TRUE, IS_FALSE, STARTS_WITH, ENDS_WITH, REGEX, CONTAINS. Depending on the type, you will need to also set the value or values property.

valuestring

The single value to filter the field on

Must be set according to its type.

valuesarray
SubTypestring

The list of values to filter the field on

Must be set for the following types: IN, NOT_IN.

id*Requiredstring
Min length1

A unique identifier for the filter

operandstring
DefaultAND
Possible Values
ANDOR

The operand to apply between all filters of the precondition

SubTypestring
Default[ "SUCCESS", "WARNING", "FAILED", "KILLED", "CANCELLED", "RETRIED", "SKIPPED", "RESUBMITTED", "PAUSED" ]
Possible Values
CREATEDSUBMITTEDRUNNINGPAUSEDRESTARTEDKILLINGSUCCESSWARNINGFAILEDKILLEDCANCELLEDQUEUEDRETRYINGRETRIEDSKIPPEDBREAKPOINTRESUBMITTED

List of execution states that will be evaluated by the trigger

By default, only executions in a terminal state or in the PAUSED state will be evaluated. Any ExecutionStatus-type condition will be evaluated after the list of states. Note that a Flow trigger cannot react to the CREATED state because the Flow trigger reacts to state transitions. The CREATED state is the initial state of an execution and does not represent a state transition.

SubTypestring
Possible Values
CREATEDSUBMITTEDRUNNINGPAUSEDRESTARTEDKILLINGSUCCESSWARNINGFAILEDKILLEDCANCELLEDQUEUEDRETRYINGRETRIEDSKIPPEDBREAKPOINTRESUBMITTED

List of execution states after which a trigger should be stopped (a.k.a. disabled).

The execution ID that triggered the current flow

The execution labels that triggered the current flow

The flow ID whose execution triggered the current flow

The flow revision that triggered the current flow

The namespace of the flow that triggered the current flow

Possible Values
CREATEDSUBMITTEDRUNNINGPAUSEDRESTARTEDKILLINGSUCCESSWARNINGFAILEDKILLEDCANCELLEDQUEUEDRETRYINGRETRIEDSKIPPEDBREAKPOINTRESUBMITTED

The execution state

The extracted outputs from the flow that triggered the current flow