Provides step-by-step instructions that guide you through the process of defining four operations for the MakeCheckAppt service
interface.
Restriction: This topic applies only when the Enterprise Server feature is enabled.
Each service interface you create is comprised of a set of operations. In this section of the tutorial, you create one operation
for each of the two functions provided by the application.
Tip: As you define these operations, we recommend that you save your work periodically. You can do this at any point you choose
and as often as you like by clicking
File > Save MakeCheckAppt.svi from the Visual Studio menu.
Note: By default,
Visual COBOL creates REST operations that use the HTTP POST method, which enables the sending of a REST request.
MakeAppt Operation
The purpose of the MakeAppt operation is to create an appointment and store it in the system.
- Create the MakeAppt Operation
-
- From the main menu, click
Operation > New.
- In the
Name field, type
MakeAppt.
This application contains only one program,
schedule.cbl, which appears on the
Select program/copybook list.
- From the
Select program/copybook list, select
schedule.
The name of each entry point contained in the program appears farther down on the dialog box.
- From the
Select entry point list, select
SCHEDULE. The entry point code appears to its right.
- Click
OK.
In the
Interface Mapper, you now see that the entry point fields have been placed into the
COBOL Entry Point pane on the left.
- Define Interface Fields
- The Schedule program needs several input items to create an appointment, including variable information such as the customer's
name, the identification number of the consultant with whom the appointment is to be made, the date of the proposed appointment,
and the desired time slot. You define interface fields to hold this information so that the client can send it to the application.
- Drag the following fields from the
COBOL Entry Point pane to the
Interface Fields pane:
- lnk-customer-name
- lnk-consultant-id
- lnk-yyyy
- lnk-mm
- lnk-dd
- lnk-time-slot
This creates interface field names similar to those of the entry point fields from which they were created. The difference
is that all dashes (-) are automatically replaced with underscores (_). In addition, a mapping is automatically created between
each new interface field and its corresponding entry point field.
The purpose of the
lnk_customer_name,
lnk_consultant_id,
lnk_yyyy,
lnk_mm,
lnk_ddand
lnk_time_slot fields are to hold data that is sent to the application for processing; therefore, they are input fields. The default mapping
direction for each of these,
Input, is correct.
Because this is a JSON service, all fields of the same direction must share a structure to represent the root object in the
JSON request or response. Currently, this operation has multiple input fields; therefore those fields must be put into a group.
- Select all the fields in the
Interface Fields pane; then right-click and select
Group.
- On the
Group Properties dialog box, type
root_in into the
Name field, and then click
OK.
Note: The default values for
Occurs (0),
Direction (Input), and
Location (Body) are correct.
Once the Schedule program receives the input information from the client, it sends back a code to indicate whether or not
the requested appointment is available. The program field that receives this code is
lnk-op-ok. Therefore, you need to create a corresponding interface field, and change its mapping direction from
Input (default) to
Output.
- Drag the
lnk-op-ok field from the
COBOL Entry Point pane to the
Interface Fields pane.
- In the
Direction column for the
lnk_op_ok interface field, double-click
Input and use the drop-down list to change the direction of the field to
Output.
- Define COBOL Assignments
- Because the MakeAppt operation executes only one program function, the value required to initialize that function remains
constant. In this case, you create a COBOL Assignment field rather than an interface field, and assign it the value required
by the program to ensure the execution of the specific function.
From looking at the program source code, you know that when the value in the
lnk-operation field is
0, the program executes the
set-appt code. Therefore, you want to assign the
lnk-operation field a value of
0.
- Drag the
lnk-operation field from the
COBOL Entry Point pane to the
COBOL Assignments pane.
- In the
Value field, type
0; then click
OK.
For this particular service, you want to make appointments only for one specific store. When the Schedule program executes,
it reads the value in the
lnk-id field to identify the store where the appointment is to be made. Therefore, you can provide the same store identification
number each time the service runs by assigning a constant value.
- In the
COBOL Entry Point pane, expand the
lnk-store-info group.
- Drag the
lnk-id field from the
COBOL Entry Point pane to the
COBOL Assignments pane.
- In the
Value field, type
08780; then click
OK.
- Click
File > Save MakeCheckAppt.svi to save the service interface.
- Completed MakeAppt Operation
CheckAppt Operation
The purpose of the CheckAppt operation is to look up an existing appointment and return its details.
- Create the CheckAppt Operation
-
- From the main menu, click
Operation > New.
- In the
Name field, type
CheckAppt.
The
Select program/copybook list shows only the
schedule program, which is already selected for you. This is because each service interface can use only one program, and you specified
the
schedule program in the MakeAppt operation you defined earlier for this same service interface.
- From the
Select entry point list, select
SCHEDULE. The entry point code appears to its right.
- Click
OK.
In the
Interface Mapper, the entry point fields once again appear in the
COBOL Entry Point pane on the left.
- Define Interface Fields
- The CheckAppt operation uses most of the same interface fields as does the MakeAppt operation, and in addition includes an
output array in which the queried appointment appears, if found. Follow these steps:
- Drag the following fields from the
COBOL Entry Point pane to the
Interface Fields pane:
- lnk-customer-name
- lnk-consultant-id
- lnk-yyyy
- lnk-mm
- lnk-dd
Because there are multiple input fields, they must be grouped to represent the JSON request structures.
- Select all fields in the
Interface Fields pane, right-click, and then select
Group from the context menu.
- On the
Group Properties dialog box, type
root_in into the
Name field, and then click
OK.
Note: The default values for
Occurs (0),
Direction (Input), and
Location (Body) are correct.
- Drag the
lnk-op-ok field from the
COBOL Entry Point pane to the
Interface Fields pane.
- In the
COBOL Entry Point pane, expand the
lnk-day group.
- Drag the
lnk-cust-id field to the
Interface Fields pane.
Because both
lnk_op_ok and
lnk_cust_id need to be output fields, you need to group them and change their direction to represent the JSON response structures.
- In the
Interface Fields pane, select the
lnk_op_ok and
lnk_cust_id fields, right-click, and then select
Group from the context menu.
- On the
Group Properties dialog box, type
root_out into the
Name field.
- Select
Output, and then click
OK.
Note: The default values for
Occurs (0) and
Location (Body) are correct.
- Define COBOL Assignments
- The CheckAppt operation needs to execute the
read-appt application code. Therefore, you need to assign the
lnk-operation field a value of
1.
- Drag the
lnk-operation field from the
COBOL Entry Point pane to the
COBOL Assignments pane.
- In the
Value field, type
1; then click
OK.
Just as you did for the MakeAppt operation, you want to assign a constant value for the
lnk-id field so you are sure to query the same store each time.
- In the
COBOL Entry Point pane, expand the
lnk-store-info group.
- Drag the
lnk-id field from the
COBOL Entry Point pane to the
COBOL Assignments pane.
- In the
Value field, type
08780; then click
OK.
- Click
File > Save MakeCheckAppt.svi to save the service interface.
- Close the Interface Mapper.
- The Completed CheckAppt Operation