JBang ScriptTrigger
CertifiedTrigger on JBang script condition
JBang ScriptTrigger
Trigger on JBang script condition
Polls by running an inline JBang script in a container (default image jbangdev/jbang-action) and emits when exitCondition matches. Edge mode (the default) emits only on a transition from not matching to matching, remembering the previous result in the namespace KV store. Polls every 60s by default. Accepts 'exit N' or a regex (fallback substring) matched against emitted vars; a failed run has no vars, so only 'exit N' can match a failure.
type: io.kestra.plugin.scripts.jbang.ScriptTriggerExamples
Trigger when the script fails with a specific exit code (exit 42).
id: script_trigger
namespace: company.team
triggers:
- id: script_failure
type: io.kestra.plugin.scripts.jbang.ScriptTrigger
interval: PT60S
exitCondition: "exit 42"
edge: true
containerImage: jbangdev/jbang-action
script: |
class Check {
public static void main(String[] args) {
System.exit(42);
}
}
tasks:
- id: log
type: io.kestra.plugin.core.log.Log
message: "Triggered with exitCode={{ trigger.exitCode }} (condition={{ trigger.condition }})"
Properties
exitCondition *string
Condition to match
Rendered condition evaluated after each execution; the trigger emits only when it matches. 'exit N' compares the exit code, otherwise the string is used as a regex (or substring fallback) against emitted vars (from ::{"outputs": ...}::). On a failed run no vars are available to match against, so only an 'exit N' condition can match a failure. Note that JBang itself exits with 1 on compile errors and unresolvable //DEPS, so prefer a dedicated exit code (e.g. 'exit 42') for the condition you watch.
script *string
Inline JBang script
Multi-line script executed on each poll, with the same semantics as the JBang Script task.
allowConcurrent boolean
falseSpecifies whether a trigger is allowed to start a new execution even if a previous run is still in progress.
containerImage string
jbangdev/jbang-actionContainer image for script execution
Image used by the Script task to run the inline JBang script; defaults to 'jbangdev/jbang-action'. Provide an image that includes JBang.
edge booleanstring
trueEdge trigger mode
When true (default), emit only on a transition from not matching to matching, so a condition that stays true does not fire on every poll. The previous result is kept in the namespace KV store, keyed by flow and trigger id. When false, emit on every poll that matches.
extension string
.javaScript extension
File extension to write (e.g., .java, .jsh, .kt, .groovy, .md); defaults to .java. Note that each poll starts a fresh container without a JBang cache, so .kt and .groovy scripts incur a compiler cold start (around 25-30s) on every poll.
interval string
PT1MdurationCheck interval
Interval between polls; default PT60S. The scheduler uses this to schedule the next evaluation.
quiet booleanstring
trueQuiet mode
When true (default), runs JBang with --quiet to suppress non-error logs.
stopAfter array
CREATEDSUBMITTEDRUNNINGPAUSEDRESTARTEDKILLINGSUCCESSWARNINGFAILEDKILLEDCANCELLEDQUEUEDRETRYINGRETRIEDSKIPPEDBREAKPOINTRESUBMITTEDList of execution states after which a trigger should be stopped (a.k.a. disabled).
when string
trueA condition that determines whether the trigger should run.
A Pebble expression evaluated at trigger time. The trigger fires only when the expression evaluates to a truthy value (true, a non-empty string, a non-zero number). Use this to gate trigger execution on dynamic runtime values such as execution labels, flow variables, or environment conditions.
Outputs
condition string
Rendered condition
Rendered value of the exitCondition property for this poll.
exitCode integer
Script exit code
Exit code returned by the JBang process (may be null if not available).
timestamp string
date-timeTimestamp of the event that fired the trigger
vars object
Script vars
Vars produced by the task (e.g. via ::{"outputs": {...}}:: convention). This is the main structured way to evaluate non-exit conditions on successful runs.
