Expressions

An expression is the condition on a rule. It reads fields from the action and returns true or false.

Fields

These fields are available during Destination/Lane Selection.

Field	Type	Reads
`payload`	object	the action payload
`metadata`	object	the action metadata
`tags`	map	the action’s tags
`variant`	string	the action variant
`version`	integer	the action version
`destination`	object	the selected destination, with `label`, `type`, and `tags`
`destinations`	list	every linked destination, each with `label`, `type`, and `tags`

Read nested values with dots or an index. Spread an array with [*].

payload.order.total
tags.customer
tags["customer"]
destination.type
destinations[*]

Literals

Form	Example
String	`"gold"`
Raw string	`r"^SKU-[0-9]+$"`
Number	`100`, `-5`, `3.14`
Boolean	`true`, `false`
IP address	`10.0.0.1`, `::1`
Range	`1..10`
Inline set	`{"eu" "us"}`
Named list	`$priority_tiers`

Use a range or an inline set with in. A range is inclusive. An inline set holds one type, with items separated by spaces. A named list comes from the action context. A raw string takes no escapes, which suits regex and wildcard patterns.

Functions

Function	Returns
`lower(s)`	the string in lowercase
`upper(s)`	the string in uppercase
`starts_with(s, prefix)`	true when `s` starts with the prefix
`ends_with(s, suffix)`	true when `s` ends with the suffix
`len(v)`	the length of a string, bytes, or array
`substring(s, start, end)`	part of a string, with an optional end index
`split(s, sep, limit)`	an array from a split string
`join(arr, sep)`	a string from a joined array
`concat(a, b, ...)`	one string or array from the inputs
`has_key(map, key)`	true when the map holds the key
`has_value(coll, value)`	true when the collection holds the value
`any(arr)`	true when any item in a boolean array is true
`all(arr)`	true when every item in a boolean array is true
`to_string(v)`	a scalar as a string
`lookup_json_string(json, key, ...)`	a string from inside a JSON document
`lookup_json_integer(json, key, ...)`	an integer from inside a JSON document
`regex_replace(s, pattern, repl)`	the string with the first regex match replaced (RE2 syntax, no backreferences or lookaround)
`wildcard_replace(s, pattern, repl)`	the string with the first wildcard match replaced
`url_decode(s)`	a URL-decoded string
`encode_base64(v)`	the value as Base64
`decode_base64(s)`	the Base64 string decoded
`remove_bytes(v, bytes)`	the value with the given bytes removed
`sha256(v)`	a SHA-256 digest
`uuidv4(bytes)`	a UUIDv4 from a byte source

Getting started

Fundamentals

Fields

Literals

Functions

​Fields

​Literals

​Functions

Fields

Literals

Functions