The if keyword is used to conditionally apply a subschema based on whether a certain condition is met. It allows you to define different validation rules depending on whether an instance satisfies a condition or not. The validation outcome of this keyword’s subschema has no direct effect on the overall validation result. Rather, it controls which of the then or else keywords are evaluated.

If an instance passes the validation against the if subschema, then it must also be validated against the then subschema, if present.

If an instance fails the validation against the if subschema, then it must also be validated against the else subschema, if present.

This keyword is meaningless without then and else .

The annotations are collected from this keyword’s subschema in the usual way, irrespective of whether then and else are present or not.

Examples

"$schema" : "https://json-schema.org/draft/2020-12/schema" , "type" : "object" , "properties" : { "role" : { "enum" : [ "HOD" , "professor" ] }, "HOD_Id" : { "type" : "integer" }, "professor_Id" : { "type" : "integer" } "if" : { "properties" : { "role" : { "const" : "HOD" } "then" : { "required" : [ "HOD_Id" ] }, "else" : { "required" : [ "professor_Id" ] }

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