Handle HTTP request failures in Power Automate

If the HTTP request you make in Power Automate cloud flow gets a 200 OK response, all is good but if the HTTP response has the status codes like 408 – Request Timeout, 429 – Too many requests, 522 – Connection Timeout, 404 – Not found, 400 – Bad request etc there is a problem which needs attention. This post will show you how to handle HTTP request failures using

  • Retry Policy
  • Custom Retry for requests which cannot be handled by Retry Policy
  • Take actions based on HTTP status code

Retry Policy:

A Retry Policy specifies how the action or trigger retries a request when the original request times out or fails. The retry policy handles the following HTTP status codes

  1. 408 – Request Timeout
  2. 429 – Too many requests
  3. 5xx – xx refers to any number like 500 – Internal server error, 503 – Service Unavailable, 522 – Connection timed out etc

HTTP Action supports retry policy and by default the action retries 4 times at exponentially increasing intervals if there is a request failure. To view or update the Retry Policy configuration settings for the HTTP action, navigate to settings as shown on below screenshot

If you have to retry the request for more than 4 times or set some custom interval between retries, you can do so by changing the retry policy from Default to Fixed interval or Exponential interval as shown below

Exponential Interval:

The policy waits for a random interval before sending the next request. The random interval is selected from an exponentially growing range.

Fixed Interval:

The policy waits for a specified interval before sending the next request.

There will not be any retry if the policy is set to None. For more details on the retry policies, go through this documentation from Microsoft. Find below screenshot of a Fixed Interval Retry Policy which attempts to make a HTTP request 5 more times after the first failed request with a 10-minute delay between each attempt.

The retry interval accepts value in ISO 8601 format. In the above screenshot for the interval field with value PT10M

P is the duration designator and T is the time designator, where M is the minute designator. PT5S translates to 5 seconds. For testing the policy with the HTTP action you can get sample http request links with different status codes request url’s from https://httpstat.us/.

The retry information will be logged in the flow Run history as shown below

Custom Retry for requests which cannot be handled by Retry Policy:

The retry policy handles only HTTP status codes 408, 429 and 5xx. On this section let us see how to handle the other types of HTTP status codes or non-retry-able errors. Let us take an example with a requirement to retry HTTP request with status code 400 – Bad request till the request succeeds.

Step 1: Initialize a boolean variable ExecuteHTTPAction with the default value true. For the Boolean value use the expression true.

Step 2: Add a Do until control. The loop runs for a maximum of 60 times (Default setting) until the HTTP request succeeds or the condition is met. The Left side placeholder should have the ExecuteHTTPAction variable as a value and the right side should have Boolean variable False. Use Expression to enter the Boolean variable false.

Toggle between Edit in advance mode and Edit in basic mode if the right side placeholder to enter value is disabled.

Step 3: Add the HTTP request action and an action to Set variable ExecuteHTTPAction named as Set Variable – HTTP Action Success. Set the value of the variable to boolean false which means on HTTP action success (200 OK), there should not be any retry.

Step 4: Once the Set variable action is added, just above the action click + and Add a parallel branch as shown in the above picture. On the other side of the branch add an action Set variable named as Set variable – HTTP Action Failure to set the ExecuteHTTPAction variable to true which means there should be retry

Step 5: The last step is to configure Run after for the action Set variable – HTTP Action Failure. Find below screenshot for the Run after configuration

No change is required for Set variable – HTTP Action Success, just ensure the Set variable – HTTP Action Failure has the Run After has failed. You can add a Delay action after the parallel branch to make sure the HTTP request is made after certain interval based on scenario. You can also add scope controls for TRY, RETRY etc.

Alternative Method:

The other way to do this without adding the parallel branch is as shown below

Take actions based on HTTP status code:

If you have to take different actions based on the HTTP status code, for example call a different API when there is an HTTP 404 – Not found etc. The quick way to do this is get the HTTP status code of the HTTP request by adding the Compose action below the HTTP request action and select the Status code from the Dynamic content which is an Output of the action HTTP.

Now configure the run after for the compose action as shown below

The compose action would now be able to capture all type of HTTP status code. With the status code in hand, add a switch control to take different actions based on HTTP status code.

Summary:

On this post we have seen how to handle different HTTP request failures codes with options to Retry in your Power Automate flow. You can apply this technique to handle HTTP request made via custom connector, SharePoint Connector etc.  Hope you have found this informational & thanks for reading. If you are visiting my blog for the first time, please do look at my other blogposts.

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