heat-config-puppet: support hiera

Updates the puppet hook so that we support using Hiera in addition
to the existing Facter based input mechanism. Hiera provides
a more flexible way of dealing with puppet parameters and
seems to be prefered in the Puppet community as well.

Use of the Hiera data will also require an additional
'hiera' element which will probably live in the
triple-puppet-elements tree.

Change-Id: I497f2d2286025e48e42691bfe178fc9c491928ea

hot/software-config/elements/heat-config-puppet/README.rst

@@ -1,3 +1,9 @@
 A hook which invokes ``puppet apply`` on the provided configuration.
-Config inputs are passed in as facts, and output values are read from written-out
-files.
+
+Config inputs are passed in as facts and/or using hiera, and output values
+are read from written-out files.
+
+Hook Options:
+-------------
+  use_facter: default True. Set to True to pass puppet inputs via Facter
+  use_hiera: default False. Set to True to pass puppet inputs via Hiera

hot/software-config/elements/heat-config-puppet/install.d/hook-puppet.py

@@ -23,6 +23,8 @@ WORKING_DIR = os.environ.get('HEAT_PUPPET_WORKING',
 OUTPUTS_DIR = os.environ.get('HEAT_PUPPET_OUTPUTS',
                              '/var/run/heat-config/heat-config-puppet')
 PUPPET_CMD = os.environ.get('HEAT_PUPPET_CMD', 'puppet')
+HIERA_DATADIR = os.environ.get('HEAT_PUPPET_HIERA_DATADIR',
+                               '/etc/puppet/hieradata')
 
 
 def prepare_dir(path):
@@ -45,11 +47,29 @@ def main(argv=sys.argv):
 
     c = json.load(sys.stdin)
 
+    use_hiera = c['options'].get('enable_hiera', False)
+    use_facter = c['options'].get('enable_facter', True)
+
     facts = {}
+    hiera = {}
+
     for input in c['inputs']:
         input_name = input['name']
-        fact_name = 'FACTER_%s' % input_name
-        facts[fact_name] = input.get('value', '')
+        input_value = input.get('value', '')
+        if use_facter:
+            fact_name = 'FACTER_%s' % input_name
+            facts[fact_name] = input_value
+        if use_hiera:
+            hiera[input_name] = input_value
+
+    if use_hiera:
+        prepare_dir(HIERA_DATADIR)
+        hiera_data = os.path.join(HIERA_DATADIR,
+                                  'heat_config_%s.json' % c['name'])
+        with os.fdopen(os.open(hiera_data, os.O_CREAT | os.O_WRONLY, 0o600),
+                       'w') as hiera_file:
+            hiera_file.write(json.dumps(hiera).encode('utf8'))
+        facts['FACTER_deploy_config_name'] = c['name']
 
     fn = os.path.join(WORKING_DIR, '%s.pp' % c['id'])
     heat_outputs_path = os.path.join(OUTPUTS_DIR, c['id'])

tests/software_config/test_hook_puppet.py

@@ -23,7 +23,12 @@ class HookPuppetTest(common.RunScriptTest):
 
     data = {
         'id': '1234',
+        'name': 'fake_resource_name',
         'group': 'puppet',
+        'options': {
+            'enable_hiera': True,
+            'enable_facter': True,
+        },
         'inputs': [
             {'name': 'foo', 'value': 'bar'},
             {'name': 'another', 'value': 'input'}
@@ -49,12 +54,14 @@ class HookPuppetTest(common.RunScriptTest):
 
         self.working_dir = self.useFixture(fixtures.TempDir())
         self.outputs_dir = self.useFixture(fixtures.TempDir())
+        self.hiera_datadir = self.useFixture(fixtures.TempDir())
         self.test_state_path = self.outputs_dir.join('test_state.json')
 
         self.env = os.environ.copy()
         self.env.update({
             'HEAT_PUPPET_WORKING': self.working_dir.join(),
             'HEAT_PUPPET_OUTPUTS': self.outputs_dir.join(),
+            'HEAT_PUPPET_HIERA_DATADIR': self.hiera_datadir.join(),
             'HEAT_PUPPET_CMD': self.fake_tool_path,
             'TEST_STATE_PATH': self.test_state_path,
         })
@@ -137,3 +144,50 @@ class HookPuppetTest(common.RunScriptTest):
                          state['env']['FACTER_heat_outputs_path'])
         with open(puppet_script) as f:
             self.assertEqual('the puppet script', f.read())
+
+    def test_hook_hiera(self):
+
+        self.env.update({
+            'TEST_RESPONSE': json.dumps({
+                'stdout': 'puppet success',
+                'stderr': 'thing happened',
+                'files': {
+                    self.outputs_dir.join('1234.first_output'): 'output 1',
+                    self.outputs_dir.join('1234.second_output'): 'output 2',
+                }
+            }),
+        })
+        returncode, stdout, stderr = self.run_cmd(
+            [self.hook_path], self.env, json.dumps(self.data))
+
+        self.assertEqual(0, returncode, stderr)
+        self.assertEqual({
+            'deploy_stdout': 'puppet success',
+            'deploy_stderr': 'thing happened',
+            'deploy_status_code': 0,
+            'first_output': 'output 1',
+            'second_output': 'output 2',
+        }, json.loads(stdout))
+
+        state = self.json_from_file(self.test_state_path)
+        puppet_script = self.working_dir.join('1234.pp')
+        hiera_datafile = self.hiera_datadir.join('heat_config_%s.json'
+                                                 % self.data['name'])
+        self.assertEqual(
+            [
+                self.fake_tool_path,
+                'apply',
+                '--detailed-exitcodes',
+                puppet_script
+            ],
+            state['args'])
+
+        self.assertEqual(self.outputs_dir.join('1234'),
+                         state['env']['FACTER_heat_outputs_path'])
+        with open(puppet_script) as f:
+            self.assertEqual('the puppet script', f.read())
+        with open(hiera_datafile) as f:
+            self.assertEqual({
+                'foo': 'bar',
+                'another': 'input',
+            }, json.loads(f.read()))