Expressions

SuperPlane uses Expr for expressions. Expressions let you access payload data, transform values, and evaluate conditions.

Accessing Payload Data

Use $['Node Name'] to access payload data from any upstream node in the message chain:

$['Node Name'].field
$['Node Name'].nested.field
$['Node Name'].array[0].value

Examples:

$['GitHub onPush'].ref                              // Branch ref
$['GitHub onPush'].head_commit.message              // Commit message
$['Deploy 10%'].workflow_run.html_url               // Workflow URL

SuperPlane Functions

These functions are specific to SuperPlane workflows:

Function	Description	Example
root()	Returns the root payload that started the run	root().data.ref
previous()	Returns payload from the immediate upstream node	previous().data.status
previous(n)	Walk n levels upstream	previous(2).data.version

Common Functions

Expr provides a rich set of built-in functions:

String lower(), upper(), trim(), split(), replace(), indexOf(), hasPrefix(), hasSuffix()

Array filter(), map(), first(), last(), len(), any(), all(), count(), join()

Date now(), date(), duration() — with methods like .Year(), .Month(), .Day(), .Hour()

Type Conversion int(), float(), string(), toJSON(), fromJSON(), toBase64(), fromBase64()

For the complete function reference, see the Expr language documentation.

Using Expressions in Configuration

Expressions can be used in component configuration fields using double curly braces:

Dynamic message:

Deployment of {{$['Listen to new Releases'].data.release.name}} has failed.

Filter expression:

$['GitHub onPush'].ref == "refs/heads/main"

String manipulation:

indexOf(lower($['Slack Message'].data.text), "p1") != -1

Conditional logic:

$['Check for alerts'].data.status != "clear" || $['Health Check'].data.body.healthy == false