Updating Approval Details in SharePoint Library using ‘Send HTTP Request to SharePoint’ in Power Automate

In Power Automate, there are two methods for updating file properties:

1. Send HTTP Request to SharePoint
2. Update File Properties

While the latter suffices for most cases, I opted for the “Send HTTP Request to SharePoint” in specific scenarios:

• To avoid triggering a new file version using system update.
• When modifying system columns such as author or modified date.
• When updating an image column.
• To update fields without having to fill in required fields.

Upon approval of a document, I needed to update file properties with the approval outcome, comments, date, and approver without generating a new version. This necessitated the use of the “Send HTTP Request to SharePoint” action.

After several iterations overcoming some challenges, the fields were successfully updated:

In my scenario, I employed the “First to Respond” approval type:

After the approval is completed, the approval details are saved back to the SharePoint library.

Capturing Details from Completed Approval Steps

Approver

Initially, I used the syntax

i:0#.f|membership|outputs('Get_user_profile_(V2)')?['body/mail'].

The flow succeeded and the step did not throw any exceptions despite the approver field was not updated.

I found the accurate syntax for updating a person field by examining the network trace in the developer tools of the browser by simulating the update of a person field in SharePoint and capture the corresponding API call. The claims of the user need to be passed with a key property to update the person field.

[{'Key': 'i:0#.f|membership|@{outputs('Get_user_profile_(V2)')?['body/mail']}'}]

Date

The date needs to be tweaked for the correct datetime string, otherwise you might encounter the following error message.

“You must specify a valid date within the range of 01/01/1900 and 31/12/8900.”

I used the following datetime format ‘dd/MM/yyyy HH:mm’.

formatDateTime(outputs('Start_and_wait_for_an_approval')?['body/completionDate'],'dd/MM/yyyy HH:mm')

However, there were issues with the date format. For instance, if the date column type is “date only,” providing ‘dd/MM/yyyy HH:mm’ as the format will result in the following error:

After updating the column to include time, using the date format still produced an exception. This was due to the regional settings for the site being set to En-US instead of En-UK. After rectifying this in the site settings under “Regional Settings” (/_layouts/15/regionalsetng.aspx), the issue was resolved:

Comments

I initially accessed the comments using the expression:

outputs('Start_and_wait_for_an_approval')?['body/responses'][0]['comments']

However if no comments are provided during approval, the flow fails.

To prevent the error I used the ‘?’. This is particularly useful for navigating through potentially nested structures where some properties may or may not exist. For instance, if outputs(‘Start_and_wait_for_an_approval’) returns an object, and it has a property body which is also an object, and within that, there’s a property responses which is an array, the ?[0] ensures that you’re trying to access the first element of that array only if it exists.

outputs('Start_and_wait_for_an_approval')?['body/responses']?[0]?['comments']

References

Working with the SharePoint Send HTTP Request flow action in Power Automate

SP.ListItem.validateUpdateListItem Method

Parsing JSON in Power Apps by the amazing Cat Schneider

• PowerAutomate
• Approval
• SharePoint
• Send HTTP Request to SharePoint