execution_field_size_limit_kb doesn't handle correctly -1 case

[Vitalii Solodilov]

The config documentation says about execution_field_size_limit_kb: "Use -1 for no limit"
But in practice Mistral trim message by 100 symbols.

Test case:
Set execution_field_size_limit_kb as -1 in mistral config.
---
version: '2.0'
wf:
  description: Test execution description
  tasks:
    task1:
      action: std.fail
      input:
        error_data:
          a: '[0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99]'

Actual result:
<output>
{"result": "Failure caused by error in tasks: task1\n\n task1 [task_ex_id=8198f9d6-e719-4dff-9a9e-9b6a97035f8c] -..."}
</output>

Expect workflow output:
<output>
{"result": "Failure caused by error in tasks: task1\n\n task1 [task_ex_id=c7f7c398-0acb-4191-a4ee-65a0d93974cb] -> {\"a\": \"[0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99]\"}\n [action_ex_id=8bbc0859-d544-403c-840a-85aa51255e0f, idx=0]: {u'a': u'[0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99]'}\n"}
</output>

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/565665

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/565665
Committed: https://git.openstack.org/cgit/openstack/mistral/commit/?id=2e710e792d3e70c18c2636e23feb44e19284b35c
Submitter: Zuul
Branch: master

commit 2e710e792d3e70c18c2636e23feb44e19284b35c
Author: Vitalii Solodilov <email address hidden>
Date: Wed May 2 12:12:14 2018 +0400

    Fixed workflow output in case of execution_field_size_limit_kb

    Now if length parameter in cut functions will be negative value that
    there is no restriction on length.

    Change-Id: I116d0bcb5663666ba4d280237a03d687de71f549
    Closes-bug: #1768450
    Signed-off-by: Vitalii Solodilov <email address hidden>

[OpenStack Infra (hudson-openstack)]

This issue was fixed in the openstack/mistral 7.0.0.0b2 development milestone.