GoCD version detection does not work for templates

[lobsterdore]

I've encountered an issue with creating a template from code, consider this bit of config:

#!/usr/bin/env python
from gomatic import *

configurator = GoCdConfigurator(HostRestClient("localhost:8153"))
template = configurator \
    .ensure_replacement_of_template("first_pipeline")

stage = template.ensure_stage("a_stage")
job = stage.ensure_job("a_job")
job.add_task(ExecTask(['thing']))

job.ensure_artifacts({
    gocd.artifacts.Artifact.get_build_artifact('a_file')
})

configurator.save_updated_config()

If you are using a version of GoCD that is 18.3 or later then this will fail with the following error:

Traceback (most recent call last):
  File "test.py", line 16, in <module>
    configurator.save_updated_config()
  File "/Users/david.reedfrancis/workspace/jsains/tickets/smss/188/smartshop-services-gocd/.venv_Darwin_x86_64_2.7.15/lib/python2.7/site-packages/gomatic/go_cd_configurator.py", line 307, in save_updated_config
    self.__host_rest_client.post('/go/admin/restful/configuration/file/POST/xml', data, headers)
  File "/Users/david.reedfrancis/workspace/jsains/tickets/smss/188/smartshop-services-gocd/.venv_Darwin_x86_64_2.7.15/lib/python2.7/site-packages/gomatic/go_cd_configurator.py", line 346, in post
    raise RuntimeError("Could not post config to Go server (%s) [status code=%s]:\n%s" % (url, result.status_code, message))
RuntimeError: Could not post config to Go server (http://localhost:8153/go/admin/restful/configuration/file/POST/xml) [status code=409]:
"Type" is required for Artifact

Digging into the code it seems that there is a function in pipeline.py that switches how the artifact XML is created based on the GoCD version, it seems that the detection will only work for pipelines that have a group as a parent - https://github.com/gocd-contrib/gomatic/blob/master/gomatic/gocd/pipelines.py#L105

I don't think this code will ever work for templates.

[lobsterdore]

A hacky workaround for this:

#!/usr/bin/env python
from gomatic import *

def gocd_version_patcher():
    return True

configurator = GoCdConfigurator(HostRestClient("localhost:8153"))
template = configurator \
    .ensure_replacement_of_template("first_pipeline")

stage = template.ensure_stage("a_stage")
job = stage.ensure_job("a_job")
job.is_gocd_18_3_and_above = gocd_version_patcher
job.add_task(ExecTask(['thing']))

job.ensure_artifacts({
    gocd.artifacts.Artifact.get_build_artifact('a_file')
})

configurator.save_updated_config()