8 - Add a Server-Side Function

Last updated 4/04/2023

To date we have just been using client side functions. This documentation is to demonstrate how to add a server-side function.

There are two types of events in Five:

On Event - executes on the client
Do Event - executes on the server

When we ran the Portfolio application we saw that we would of been allowed to save the Sells form without the Quantity fields on the Sells and Allocations forms having an equal value, as there is no check being applied. We will add a function that will be attached to the Do Complete event on the Sells form. When the Save button is clicked on the Sells form the function will have access to the data in the tables to know whether the Quantity fields on the Sells and the Allocations forms match. Essentially, the save sends the current data on the forms to the backend, and the backend will call the function with the transactions being saved.

Navigate to the Code Editor

1. Select Logic in the menu.

2. Select Code Editor in the sub-menu.

Figure 1 - Code Editor menu item

Add the CheckValidSell Function

1. Click the Add New Code button.

Figure 2 - Add New Code button

2. Type CheckValidSell in the Function ID field.

3. Click the lookup icon in the Language field and select TypeScript.

4. Click the OKAY button

Figure 3 - Add the CheckValidSell function

5. Click the Copy button on the below code block.

CheckValidSell

function CheckValidSell(five: Five, context: any, result: FiveError) : FiveError {

    if (!context.Transactions) {
        return five.success(result);
    }

    let soldQuantity: number = 0;
    let totalAllocated: number = 0;

    for (let i = 0; i < context.Transactions.length; i++) {
        const record = context.Transactions[i];
        if (record.ActionID === 'Sells') {
            soldQuantity = Number(record.Values.Quantity);
        } else if (record.ActionID === 'Allocations') {
            totalAllocated = totalAllocated + Number(record.Values.Quantity);
        }
    }

    if (totalAllocated !== soldQuantity) {
        return five.createError(result, 'Total allocations do not match sold quantity');
    }

    return five.success(result);
}

6. Paste the code block over the template in the Code Editor.

7. Click the Save Current Tab button.

Figure 4 - Save the CheckValidSell function

Attach the CheckValidSell Function

1. Select Visual in the menu.

2. Select Forms in the menu.

Figure 5 - Forms menu item

3. Select the Sells record in the list.

4. Click the Events tab.

Figure 6 - Events tab

5. Click the lookup icon in the Do Complete field and select CheckValidSell.

Figure 7 - Attach the CheckValidSell function

6. Click the Save button in the form app bar.

Figure 8 - Save the Sells form

Run the Portfolio Application

1. Click the Run button in Five's toolbar.

Figure 9 - Run button

2. Select the Growth Portfolio record.

3. Click the Down button in the form app bar.

Figure 10 - Down button

Test the CheckValidSell Function

info

You should have still have two AEI stock records:

Yesterday's date record equals 1000
Current date record equals 120

1. Select Sells in the menu.

2. Click the Add Item button.

3. Click the lookup icon in the Stock field and select AEI.

4. Click the calendar icon in the Transaction Date field and select your current date, click the OK button.

5. Type 1100 in the Quantity field.

6. Type 1.00 in the Price field.

7. Type 10.00 in the Fees field, press tab.