13.3.6 Configuring a Request Body Template

Your operations for Insert row and Update row need to send data to the REST API in the request body.

As shown below, you configure the contents of this payload using the operation's Request Body Template. It can contain a mix of JSON syntax and #NAME# substitutions. The names of region data source columns are available to reference automatically, as well as any parameters of type Request Body you might need to define. Notice the column name substitutions are not surrounded by double quotes. At runtime APEX replaces the substitutions with appropriately escaped values that contain the double quotes if needed. If the REST API you work with requires passing a null value using the JSON null keyword instead of empty double quotes, then reference the substitution like #COMM!NULL# using the !NULL modifier.

The figure shows the Request Body Template for the Employees PUT operation. It's a JSON object template including a mix of JSON properties and data profile column substitutions.

Figure 13-18 Request Body Template in the PUT / Update Row Operation

Description of "Figure 13-18 Request Body Template in the PUT / Update Row Operation"

To build the request body template dynamically, define a Request Body parameter, for example named PAYLOAD, and configure the Request Body Template like this:

#PAYLOAD!RAW#

The PAYLOAD parameter will appear in any context where you use the REST Data Source and you can assign a dynamic value to the parameter using a PL/SQL expression. The !RAW modifier asks APEX to treat the value of the parameter verbatim, avoiding the normal JSON escaping it performs when substituting parameter or data source column values.