Has Operator

The Has operator checks whether a specific key exists in an object. When a match is found, the operator outputs a Boolean value of true; otherwise, the output is false.

It’s important to remember that the Has operator only verifies the existence of a key. It does not validate the value stored under that key or determine whether the key has a defined value. Additionally, the Has operator only searches top-level keys. It cannot detect keys nested in other objects.

Below are some considerations when using the Has operator:

• The Has operator only works with objects as inputs.

• You cannot connect a Data Table component directly to the Has operator because a table is an array of objects.

• To use the Has operator with a table, first extract a single object using the Get operator.

• The Get operator retrieves one row (object) from the array, which you can then input into the Has operator for evaluation.

Let’s say you have a Data Table listing internal and external company roles, such as Manager and Client. Another column in the table defines the permissions for each role, either Administrative or Authenticated.

1. Use a Get operator to retrieve the first row from the table.

2. Then connect the Has operator to check if a permission key exists for that role.

   In this setup, you’ll use the column header for example, permissions as the operator’s key.

3. If the first row contains a permissions key, the Has operator outputs true. If it doesn’t, the output is false.

You'll find the Has operator under the Object group to the left of the Data Workflow canvas.

About the Info Window

Here's a breakdown of each setting in the Info window:

Adding a Has Operator

In this example, you'll use the Has operator to confirm that the roleType key exists in the first row of your Data Table component. You'll use a Get operator to select the first row of the table, then use the Has operator to confirm if the key exists. If the key exists in the first row, the output of the Has operator will be true. If not, it’ll be false.

These instructions assume you have a module open, saved, and with a title.

Configure the Data Table Component

Start by configuring a Data Table component to create some sample data with roleName  and roleType columns. Now, enter four different roles in roleName column and assign each role either Administrative or Authenticated permissions in the roleType column.

1. In the Module Builder, drag and drop a Data Table component onto your canvas.

2. In the Property ID field, enter dtRoles.

3. In the data table, enter the following:

   roleName	roleType
   Manager	Administrative
   Developer	Administrative
   Customer	Authenticated
   Client	Authenticated

   

4. Click Save Component.

Configure the Data Workflow Component

Next, set up your Data Workflow and use the Has operator to confirm if the key exists. If the key exists in the first row, the output of the Has operator will be true. If not, it’ll be false.

1. Drag and drop a Data Workflow component onto your canvas, placing it below your dtRoles Data Table component.

2. In the Property ID and Canvas Label Text fields, enter dwfHasSingleObject.

Configure the Input Operator

1. Drag and drop an Input operator onto your Data Workflow canvas.

2. Configure the operator's Info window as follows:

   Setting	Value
   Category	Input
   Component	dtRoles
   Required	No
   Source	Default

Configure the Get Operator

1. Drag and drop a Get operator onto your Data Workflow canvas.

2. Configure the operator's Info window as follows:

   Setting	Value
   Category	Get
   Label	Get First Row
   Path	[0]

3. Connect the output port (right) of the dtRoles Input operator to the input port (left) of the Get First Row Get operator.

Configure the Has Operator

1. Drag and drop a Has operator onto your Data Workflow canvas.

2. Configure the operator's Info window as follows:

   Setting	Value
   Category	Has
   Label	Has roleType
   Path	roleType

3. Connect the output port (right) of the Get First Row Get operator to the input port (left) of the Has roleType Has operator.

Configure the First Console Operator

1. Drag and drop a Console operator onto your Data Workflow canvas.

2. Configure the operator's Info window as follows:

   Setting	Value
   Category	Console
   Label	dtRoles

3. Connect the output port (right) of the dtRoles Input operator to the input port (left) of the dtRoles Console operator.

Configure the Second Console Operator

1. Drag and drop another Console operator onto your Data Workflow canvas.

2. Configure the operator's Info window as follows:

   Setting	Value
   Category	Console
   Label	Get Path [0]

3. Connect the output port (right) of the Get First Row Get operator to the input port (left) of the Get Path [0] Console operator.

Configure the Third Console Operator

1. Drag and drop the final Console operator onto your Data Workflow canvas.

2. Configure the operator's Info window as follows:

   Setting	Value
   Category	Console
   Label	Path [0] Has roleType?

3. Connect the output port (right) of the Has roleType Has operator to the input port (left) of the Path [0] Has roleType? Console operator.

   

4. Click Save Component.

Configure the Button Component

Now, configure a Button component that you can click in Express View to trigger your Data Workflow.

1. Drag and drop a Button component onto your canvas, placing it below your dwfHasSingleObject Data Workflow component.

2. In the Property ID field, enter btnHasSingleObject.

3. In the Label Text field, enter Get the Has.

4. From the Action Type drop-down, select Event.

5. In the Trigger On Click field, enter dwfHasSingleObject.

   

6. Click Save Component.

7. Save your module.

Here's how the completed example looks in the Module Builder:

Here's how the completed example works in Express View, including a peek at the DevTools Console:

Preview your module in Express View, and open up the DevTools Console. Click the Get the Has button and expand the three Consoles. First, you'll see the Get operator single out the first row of your Data Table. Next, the Has operator determines if this row of the table contains the roleType key. It does, so the output from the Has operator is true.