In this article, we will understand how to create a list item in the SharePoint designer workflow using REST-API POST method. Designer workflows are a very essential part of most of the SharePoint development projects. Let’s see how we can use REST-API POST method in the designer workflow.

The step-by-step process of creating a designer workflow using REST-API POST method

You can check how to create a list item using REST-API programmatically. The same example we have utilized for reference in this article.

1. Open SharePoint Designer. Here, we have shown List workflow. Click on List Workflow from Ribbon and add workflow details. Make sure you select latest platform Type – SharePoint 2013 Workflow

2. We need to create a total of three dictionary variables.
3. In Stage 1, click on Action from Ribbon and then from dropdown select, Build Dictionary.

4. We are going to create a variable of Type Dictionary and save REST call headers in it. As shown in the screenshot below, click on the ellipsis (…) to build dictionary variable values and add headers.

Name	Type	Value
Accept	String	application/json;odata=verbose
Content-Type	String	application/json;odata=verbose


5. We will create one more dictionary to store the “type” value.
   NOTE:

   The format of the "type" is: SP.Data.<<ListName>>ListItem

Here, the list name is List Name. You need to set the dictionary value according to your list name.

The dictionary value will be as mentioned below.

Name	Type	Value
type	String	SP.Data.List_x0020_NameListItem

6. We need to create one more dictionary for the Request Content for the POST call. Along with __metadata, you can add the columns that you have in your REST call.
NOTE:
• All the column names are internal names of the columns.
• metadata has got two underscores (_) before it.

Name	Type	Value
__metadata	dictionary	The dictionary variable created in the above step
Title (Column Internal Name)	String	New Title (value for the column)
Description	String	New Description

7. Next, we will add Call HTTP Web Service action.

8. Select the web service action and then click on the Advanced Properties from Ribbon Menu.

9. Now, we will add a few values which are very essential. Here, you are constructing the actual request. Mainly we have added below three parameters.
   • Address: This is the REST API URL value. You can construct it according to your requirements.
   • RequestType: Here we have used the HTTP POST method as we are creating a list item
   • RequestHeaders: This is the headers of the REST call we will assign dictionary value that we created in the first step (HeaderDictionary)
   • RequestContent: It contains the dictionary variable for new item metadata, created in the last dictionary variable above.
   • ResponseContent: This is a variable of the type Dictionary that holds the data returning by the REST call.
   • ResponseStatusCode: This is not mandatory but just kept to check the status of the REST call
   
10. Set Transition to stage add Go to End of Workflow

11. Now you can publish this workflow.
12. Go to your list and manually start the flow (you can set the trigger of the flow according to your requirement).
13. You will notice, a list item is created.

You can check some REST-API examples and create a designer workflow with their reference.

Conclusion:

We have gone through the steps to create a designer workflow and how to create REST - POST request using that.