Force an Azure Logic App to recognise a text string as a token and replace it with the token's value at run time

Question

Details of the Azure Logic App:

• Triggered by an incoming webhook
• The triggering webhook contains a number of json name/value pairs, such as "variable1":"05-05-2021" and "variable2":"A text string"
• The first step of the Logic App is to retrieve a json object from an external source.
• The retrieved json object contains string values, some of which include text that match tokens that exist in the Logic App e.g. "triggerBody()?['variable1']" and "triggerBody()?['variable2']"
• The Logic App then posts the json object to another external source.

Is there any way to make the logic app recognise these string values as tokens and replace the string value with the value of the token?

For example

• If the retrieved json object contains the string "The date today is triggerBody()?['variable1']"
• And the triggering Webhook provided the value of variable1 as "05-05-2021"
• Is there a method I can use to force the Logic App to recognise the relevant string in the json object as a token and replace it with the token's value, so that the string in the json object becomes 'The date today is 05-05-2021"

I've tried adding steps in the app to convert the json object to a string and then back into an object, in the hope that this would force the Logic App to recognise the text triggerBody()?['variable1'] as a token and replace it with the token's value, but that's not working.

Any guidance would be greatly appreciated!

Answer 1

Unfortunately, this isn't possible. The tokens are replaced just once. The alternatives are

1. Use the replace function to do this. Though this will not work dynamically and should be OK with a small list of known variables.
2. You could use the inline function to replace tokens with values. Note that this requires an integration account.

Originally answered on Microsoft Q&A