Issue

• Following error gets thrown in APICast logs, each time we call the API service.

  2050/01/01 00:00:01 [error] 32#32: *1234567 lua entry thread aborted: runtime error: /opt/app-root/src/src/apicast/policy/headers/headers.lua:91: attempt to index field 'template_string' (a nil value)
  stack traceback:
  coroutine 0:
      /opt/app-root/src/src/apicast/policy/headers/headers.lua: in function 'run_commands'
      /opt/app-root/src/src/apicast/policy/headers/headers.lua:151: in function </opt/app-root/src/src/apicast/policy/headers/headers.lua:147>
      /opt/app-root/src/src/apicast/policy_chain.lua:200: in function 'rewrite'
      ...-root/src/src/apicast/policy/local_chain/local_chain.lua:59: in function <...-root/src/src/apicast/policy/local_chain/local_chain.lua:54>
      /opt/app-root/src/src/apicast/policy_chain.lua:200: in function 'rewrite'
  

• We try to remove the rewrite policy and republish with no success and try both with the 1.16-41 version of apicast and the 1.18-0 more recent version => same error.

• A direct curl to the private backend from the server that runs the APICast docker images works.
• How to resolve this issue?