heat API : Add api.aws.utils.extract_param_list

Add new common helper function which extracts
AWS parameter lists

Change-Id: Ic77ff6014a4f39d4fb5d59a1391f87cdd94f0f7f
Signed-off-by: Steven Hardy <shardy@redhat.com>

diff --git a/heat/api/aws/utils.py b/heat/api/aws/utils.py
index afce0a942bbe2006256aeeaf14ff5a2f1e373917..aecc509f2740888a30cb61cf5bc17b5063678ed8 100644 (file)
--- a/heat/api/aws/utils.py
+++ b/heat/api/aws/utils.py
@@ -68,6 +68,52 @@ def extract_param_pairs(params, prefix='', keyname='', valuename=''):
     return dict(get_param_pairs())
 
 
+def extract_param_list(params, prefix=''):
+    """
+    Extract a list-of-dicts based on parameters containing AWS style list
+
+    MetricData.member.1.MetricName=buffers
+    MetricData.member.1.Unit=Bytes
+    MetricData.member.1.Value=231434333
+    MetricData.member.2.MetricName=buffers2
+    MetricData.member.2.Unit=Bytes
+    MetricData.member.2.Value=12345
+
+    This can be extracted by passing prefix=MetricData, resulting in a
+    list containing two dicts
+    """
+
+    key_re = re.compile(r"%s\.member\.([0-9]*?)\.(.*?)$" % (prefix))
+    result = []
+    for k in params:
+        keymatch = key_re.match(k)
+        if keymatch:
+            try:
+                index = int(keymatch.group(1))
+            except ValueError:
+                # Regex match should mean this never happens..
+                logger.error('Could not extract index %s' % keymatch.group(1))
+                continue
+
+            key = keymatch.group(2)
+            try:
+                value = params[k]
+            except KeyError:
+                logger.error('Could not extract parameter for %s' % key)
+                continue
+
+            # We can't rely on list indexes being in-order, so
+            # populate the list with empty dicts up to the current
+            # index value if index > current list length
+            # We then merge the result into the appropriate dict
+            if index > len(result):
+                while len(result) < index:
+                    result.append({})
+            result[index - 1].update({key: value})
+
+    return result
+
+
 def reformat_dict_keys(keymap={}, inputdict={}):
     '''
     Utility function for mapping one dict format to another

diff --git a/heat/tests/test_api_aws.py b/heat/tests/test_api_aws.py
index 40c8f085cd477658dab625573c5b2152f883fa54..ba3bf1f614b0b28ff8d3d1d0e02316b7b6bc23ab 100644 (file)
--- a/heat/tests/test_api_aws.py
+++ b/heat/tests/test_api_aws.py
@@ -92,6 +92,97 @@ class AWSCommon(unittest.TestCase):
                                               valuename='ParameterValue')
         self.assertFalse(params)
 
+    def test_extract_param_list(self):
+        p = {'MetricData.member.1.MetricName': 'foo',
+              'MetricData.member.1.Unit': 'Bytes',
+              'MetricData.member.1.Value': 234333}
+        params = api_utils.extract_param_list(p, prefix='MetricData')
+        self.assertEqual(len(params), 1)
+        self.assertTrue('MetricName' in params[0])
+        self.assertTrue('Unit' in params[0])
+        self.assertTrue('Value' in params[0])
+        self.assertEqual(params[0]['MetricName'], 'foo')
+        self.assertEqual(params[0]['Unit'], 'Bytes')
+        self.assertEqual(params[0]['Value'], 234333)
+
+    def test_extract_param_list_garbage_prefix(self):
+        p = {'AMetricData.member.1.MetricName': 'foo',
+              'MetricData.member.1.Unit': 'Bytes',
+              'MetricData.member.1.Value': 234333}
+        params = api_utils.extract_param_list(p, prefix='MetricData')
+        self.assertEqual(len(params), 1)
+        self.assertTrue('MetricName' not in params[0])
+        self.assertTrue('Unit' in params[0])
+        self.assertTrue('Value' in params[0])
+        self.assertEqual(params[0]['Unit'], 'Bytes')
+        self.assertEqual(params[0]['Value'], 234333)
+
+    def test_extract_param_list_garbage_prefix2(self):
+        p = {'AMetricData.member.1.MetricName': 'foo',
+              'BMetricData.member.1.Unit': 'Bytes',
+              'CMetricData.member.1.Value': 234333}
+        params = api_utils.extract_param_list(p, prefix='MetricData')
+        self.assertEqual(len(params), 0)
+
+    def test_extract_param_list_garbage_suffix(self):
+        p = {'MetricData.member.1.AMetricName': 'foo',
+              'MetricData.member.1.Unit': 'Bytes',
+              'MetricData.member.1.Value': 234333}
+        params = api_utils.extract_param_list(p, prefix='MetricData')
+        self.assertEqual(len(params), 1)
+        self.assertTrue('MetricName' not in params[0])
+        self.assertTrue('Unit' in params[0])
+        self.assertTrue('Value' in params[0])
+        self.assertEqual(params[0]['Unit'], 'Bytes')
+        self.assertEqual(params[0]['Value'], 234333)
+
+    def test_extract_param_list_multiple(self):
+        p = {'MetricData.member.1.MetricName': 'foo',
+              'MetricData.member.1.Unit': 'Bytes',
+              'MetricData.member.1.Value': 234333,
+              'MetricData.member.2.MetricName': 'foo2',
+              'MetricData.member.2.Unit': 'Bytes',
+              'MetricData.member.2.Value': 12345}
+        params = api_utils.extract_param_list(p, prefix='MetricData')
+        self.assertEqual(len(params), 2)
+        self.assertTrue('MetricName' in params[0])
+        self.assertTrue('MetricName' in params[1])
+        self.assertEqual(params[0]['MetricName'], 'foo')
+        self.assertEqual(params[0]['Unit'], 'Bytes')
+        self.assertEqual(params[0]['Value'], 234333)
+        self.assertEqual(params[1]['MetricName'], 'foo2')
+        self.assertEqual(params[1]['Unit'], 'Bytes')
+        self.assertEqual(params[1]['Value'], 12345)
+
+    def test_extract_param_list_multiple_missing(self):
+        # Handle case where there is an empty list item
+        p = {'MetricData.member.1.MetricName': 'foo',
+              'MetricData.member.1.Unit': 'Bytes',
+              'MetricData.member.1.Value': 234333,
+              'MetricData.member.3.MetricName': 'foo2',
+              'MetricData.member.3.Unit': 'Bytes',
+              'MetricData.member.3.Value': 12345}
+        params = api_utils.extract_param_list(p, prefix='MetricData')
+        self.assertEqual(len(params), 3)
+        self.assertTrue('MetricName' in params[0])
+        self.assertTrue('MetricName' in params[2])
+        self.assertEqual(params[0]['MetricName'], 'foo')
+        self.assertEqual(params[0]['Unit'], 'Bytes')
+        self.assertEqual(params[0]['Value'], 234333)
+        self.assertEqual(params[2]['MetricName'], 'foo2')
+        self.assertEqual(params[2]['Unit'], 'Bytes')
+        self.assertEqual(params[2]['Value'], 12345)
+
+    def test_extract_param_list_badindex(self):
+        p = {'MetricData.member.xyz.MetricName': 'foo',
+              'MetricData.member.$!&^.Unit': 'Bytes',
+              'MetricData.member.+.Value': 234333,
+              'MetricData.member.--.MetricName': 'foo2',
+              'MetricData.member._3.Unit': 'Bytes',
+              'MetricData.member.-1000.Value': 12345}
+        params = api_utils.extract_param_list(p, prefix='MetricData')
+        self.assertEqual(len(params), 0)
+
     def test_reformat_dict_keys(self):
         keymap = {"foo": "bar"}
         data = {"foo": 123}