Choice state

A Choice state adds conditional logic to a ZIS flow.

             

              
"PickChoice":{"Type":"Choice","Choices":[{"Variable":"$.input.value","StringEquals":"Choice A","Next":"NextStateA"},{"Variable":"$.input.value","StringEquals":"Choice B","Next":"NextStateB"}],"Default":"NextStateC"}
             

Supported properties

In addition tocommon state properties, a Choice state supports the following properties.

Choice rules

A choice rule object contains a boolean expression. The expression is acomparisonthat evaluates to true or false. When run, the Choice state evaluates each rule in theChoicesarray in the order provided. The ZIS flow runs theNextstate of the first rule that evaluates to true. If no rule in theChoicesarray is true, the flow runs theDefaultstate.

A choice rule object requires the following properties:

• AVariablethat contains aJSON reference pathto an input value
• Acomparison operator
• TheNextstate to run in the ZIS flow if the rule evaluates to true

The object also supports an optionallogical operator.

Comparisons

To evaluate a rule, a Choice state compares the inputVariableto the value of the comparison operator. For example, the following state compares$.ticket.priorityto a staticStringEqualsvalue.

             

              
"Choice.CheckTicketPriority":{"Type":"Choice","Choices":[{"Variable":"$.ticket.priority","StringEquals":"Urgent","Next":"EscalateTicketStep"}],"Default":"NormalTicketStep"}
             

To compare the input variable to a reference path, appendPathto theStringEqualskey.

Note:Some comparison operators don't support aPathsuffix. Seecomparison operators.

             

              
"Choice.CheckTicketPriority":{"Type":"Choice","Choices":[{"Variable":"$.ticket.priority","StringEqualsPath":"$.settings.ticket_priority","Next":"EscalateTicketStep"}],"Default":"NormalTicketStep"}
             

Comparison operators

A Choice state supports the following comparison operators.

Logical operators

Use logical operators to combine or negate choice rules in a choice rule object. A Choice state supports the following logical operators:

• Not
• And
• Or

Notexample:

             

              
"Choice.TicketNotClosed":{"Type":"Choice","Choices":[{"Not":{"Variable":"$.jq_result","StringEquals":"Closed"},"Next":"ActiveTicketStep"}],"Default":"ClosedTicketStep"}
             

Andexample:

             

              
"Choice.WaitingUrgentTicket":{"Type":"Choice","Choices":[{"And":[{"Variable":"$.ticket.status","StringEquals":"New"},{"Variable":"$.ticket.priority","StringEquals":"Urgent"}],"Next":"EscalateTicketStep"}],"Default":"NormalTicketStep"}
             

Orexample:

             

              
"Choice.TicketTopPriorities":{"Type":"Choice","Choices":[{"Or":[{"Variable":"$.ticket.priority","StringEquals":"High"},{"Variable":"$.ticket.priority","StringEquals":"Urgent"}],"Next":"EscalateTicketStep"}],"Default":"NormalTicketStep"}
             

Example

For an example of a Choice state in a ZIS flow, seeUsing conditional branching in a ZIS flow.

Limitations

A ZIS Choice state doesn't support all comparison operators from theAmazon State Language. For supported operators, seeComparison operators.