JSONSelector
Specify which record member needs to be serialized or deserialized.
Syntax
JSONSelector is a mandatory attribute used with JSONOneOf.
Usage
In an operation that you set JSONOneOf to specify members of a record or a
user-defined type that need to be serialized or
deserialized, you must set the JSONSelector on a specific member of the record to
perform the selection. This specific member must be of type SMALLINT or INTEGER.
The JSONSelector attribute supports the oneOf keyword in the
JSON schema property of the Swagger and OpenAPI specifiaction.
Example using JSONSelector and JSONOneOf
In this example, the JSONSelector attribute is set on the
_selector member in the input record of the CreateAccount
function. At a request to the
service, you can choose which member of the createAccountType record –
id or name – to use by setting the _selector to
the index value of the record member. For example, to specify the name, in the
client set _selector to 2 in the statement LET
in._SELECTOR=2.
In the CreateAccount function, the CASE
statement tests for the _selector value.
IMPORT COM
PUBLIC TYPE accountType RECORD
id INTEGER,
name STRING,
date DATETIME YEAR TO SECOND,
age INTEGER,
gender BOOLEAN
END RECORD
PRIVATE DEFINE accounts DYNAMIC ARRAY OF accountType
PUBLIC DEFINE accountError RECORD ATTRIBUTE(WSError = 'account service error')
id INTEGER,
msg STRING
END RECORD
TYPE createAccountType RECORD ATTRIBUTE(JSONOneOf)
_selector INTEGER ATTRIBUTE(JSONSelector),
id INTEGER,
name STRING
END RECORD
FUNCTION CreateAccount(
in createAccountType)
ATTRIBUTE(WSPost, WSPath = "/createaccount")
RETURNS(createAccountType)
DEFINE out createAccountType
DEFINE idx INTEGER
LET out = in
CASE
WHEN in._selector = 1
LET idx = accounts.search("id", in.id)
IF idx > 0 THEN
# raise RESTError with accountError
ELSE
CALL accounts.appendElement()
LET accounts[accounts.getLength()].id = in.id
END IF
WHEN in._selector = 2
LET idx = accounts.search("name", in.name)
# ... function code ...
END CASE
RETURN out
END FUNCTION