st2 rule ValidationError after upgrade from st2 2.6.0 to 2.7.2 (Jinja not rendering properly?)

ISSUE TYPE

• Bug Report

STACKSTORM VERSION

st2 2.7.2, on Python 2.7

OS / ENVIRONMENT / INSTALL METHOD

RPM installation on CentOS 7.x

SUMMARY

I have an st2 rule definition that was previously working fine under st2 2.6.0. After upgrading to st2 2.7.2 (with no changes to the rule definition), I am now finding it is throwing a ValidationError against one of the action parameters in the rule definition:

Traceback (most recent call last):
  File "/opt/stackstorm/st2/lib/python2.7/site-packages/st2reactor/rules/enforcer.py", line 94, in enforce
    execution_db = self._do_enforce()
  File "/opt/stackstorm/st2/lib/python2.7/site-packages/st2reactor/rules/enforcer.py", line 143, in _do_enforce
    additional_contexts=additional_contexts)
  File "/opt/stackstorm/st2/lib/python2.7/site-packages/st2reactor/rules/enforcer.py", line 199, in _invoke_action
    liveaction_db, execution_db = action_service.create_request(liveaction_db)
  File "/opt/stackstorm/st2/lib/python2.7/site-packages/st2common/services/action.py", line 89, in create_request
    allow_default_none=True)
  File "/opt/stackstorm/st2/lib/python2.7/site-packages/st2common/util/schema/__init__.py", line 294, in validate
    jsonschema.validate(instance=instance, schema=schema, cls=cls, *args, **kwargs)
  File "/opt/stackstorm/st2/lib/python2.7/site-packages/jsonschema/validators.py", line 541, in validate
    cls(schema, *args, **kwargs).validate(instance)
  File "/opt/stackstorm/st2/lib/python2.7/site-packages/jsonschema/validators.py", line 130,
   in validate
    raise error
ValidationError: u'{{trigger.body.pullrequest_id}}' is not of type u'integer'
Failed validating u'type' in schema['properties'][u'prid']:
    {u'description': u'Pull request ID',
     u'required': True,
     u'type': u'integer'}

however the actual trigger body payload for the rule from st2rulesengine.log seems to be the correct (integer) type:

'payload': {'body': {u'request_user': u'ReRunner', u'pullrequest_id': 2401, ...

Seems like st2 is not rendering the Jinja before validating it.

As suggested in Slack, I also tried casting the parameter with | int in the rule definition but that doesn't appear to address the problem, still seems like the Jinja isn't rendered.

Here's my rule declaration:

---
    name: "reset_pr_bldstat"
    pack: "pxops"
    description: "Reset pull request build status"
    enabled: true
    trigger:
        type: "core.st2.webhook"
        description: "Reset PR build status incoming webhook"
        parameters:
          url: "pr/build/status/reset"
    criteria:
        trigger.body.webhook_event:
          type: "equals"
          pattern: "prbuild_reset_status"
    action:
         ref: "pxops.reset_build_status"
         parameters:
            repo: "{{trigger.body.repository}}"
            prid: "{{trigger.body.pullrequest_id}}"
            requestUser: "{{trigger.body.request_user}}"

This seems similar to this issue: https://github.com/StackStorm/st2/issues/4050

Some discussion of this on the Slack forum:

https://stackstorm-community.slack.com/archives/C066APT88/p1527787880000773

Reproduce the rule using the supplied StackStorm 2.7.2 configuration and webhook payload. Start in st2reactor/rules/enforcer.py and st2common/services/action.py, then follow the schema validation in st2common/util/schema/init.py. Compare the Jinja parameter handling with 2.6.0 and verify that the integer parameter validates before action creation.