Introduction
Problem:
A user may encounter the following error during a terraform run on TFE:
Error fetching plan data
Cannot read properties of null (reading 'length')
Cause:
This is a known issue affecting TFE releases prior to 202210-1 . It is triggered when JSON-encoded arrays are compared with null values.
Overview of possible solutions
Solutions:
1. Switch the Workspace's User Interface Setting from Structured Run Output to Console UI.
OR
2. Upgrade to Terraform Enterprise 202210-1 (659) or later.
Outcome:
After applying one of the solutions, retry the failed run and it should not run into this error.