switch

Branch on a variable’s value, with optional text transforms applied before matching. Useful for keyword-driven inbound message handling.

After the selected branch runs, execution continues with the next step after switch, unless the branch moves execution elsewhere (for example with goto, return, or transfer), a step fails, or the document reaches its 100-step limit.

Properties

objectRequired

An object that accepts the following properties.

switch.variable

stringRequired

Variable path to match. Specified without the %{} wrapper (e.g. message.body). The resolved value is converted to a string, then transformed and compared exactly with the case keys. A missing variable path resolves to an empty string.

switch.transform

string

Transform to apply to the value before matching. One of lowercase, uppercase, trim, lowercase_trim, or uppercase_trim.

switch.case

objectRequired

Map of values to arrays of SWML methods to execute. The key is the value to compare against variable (after applying transform); the value is the array of methods to run on match. Keys are literal and are not transformed, and matching is exact. An empty-string key matches a missing variable; otherwise default is used.

switch.default

object[]

Array of SWML methods to execute if no case matches. If omitted and no case matches, execution stops with an error.

Examples

Keyword-based reply

The request after the switch runs after whichever branch was taken.

version: 1.0.0
sections:
  main:
    - switch:
        variable: message.body
        transform: lowercase_trim
        case:
          help:
            - reply:
                body: "Reply STOP to unsubscribe, or visit https://example.com/help."
          stop:
            - reply:
                body: "You've been unsubscribed."
          start:
            - reply:
                body: "Welcome back!"
        default:
          - reply:
              body: "Sorry, I didn't understand that. Reply HELP for assistance."
    - request:
        url: "https://api.example.com/keyword-log"
        body:
          from: "%{message.from}"
          keyword: "%{message.body}"

Branch on a saved request response

version: 1.0.0
sections:
  main:
    - request:
        url: "https://api.example.com/customer"
        body:
          phone: "%{message.from}"
        save_variables: true
    - switch:
        variable: request_response.tier
        case:
          gold:
            - reply:
                body: "Welcome back, valued customer!"
          silver:
            - reply:
                body: "Thanks for being a member."
        default:
          - reply:
              body: "Thanks for your message."