Custom runner: cs
...
def meta_get(name, node_keys):
    log.debug('Requested keys for meta_get: {0}'.format(node_keys))
    cs_node = _get_cs_node(name)
    if not cs_node:
        log.debug('{0} CS node is missing, returning values as "unknown"\
                  '.format(name))
        data = {k: 'unknown' for k in node_keys}
        return data
    data = {k: str(cs_node[k]) if k in cs_node else 'unknown' for k in node_keys}
    log.debug('{0} node requested metadata: {1}'.format(name, data))
    return data
...

sls that uses the runner calling it via peer communication:
update_grains = ['kernel']
...
{% set meta_args = ['name='~ minion_fqdn ~',node_keys='~ update_grains ] %}
{% set cs_metadata = salt['publish.runner']('cs.meta_get', meta_args, timeout=20) %}
...

The second argument doesnt seen to get there:
Traceback (most recent call last):
  File "/usr/lib/python2.7/dist-packages/salt/master.py", line 1329, in run_func
    ret = getattr(self, func)(load)
  File "/usr/lib/python2.7/dist-packages/salt/master.py", line 1199, in minion_runner
    return self.masterapi.minion_runner(clear_load)
  File "/usr/lib/python2.7/dist-packages/salt/daemons/masterapi.py", line 782, in minion_runner
    return runner.run()
  File "/usr/lib/python2.7/dist-packages/salt/runner.py", line 238, in run
    self.opts['fun'], self.opts['arg'], self.opts)
  File "/usr/lib/python2.7/dist-packages/salt/runner.py", line 122, in cmd
    return self.functions[fun](*args, **kwargs)
TypeError: meta_get() takes exactly 2 arguments (1 given)