Added a module for intrinsic function.

Curenntly only handles get_ref_property specified in interface operation
input.

Renamed ntype to node_type.

Change-Id: I4d95b28faba9b55a5d16b9f16dbe36bd3bcd5b4d
Implements: blueprint tosca-ref-property

.gitignore

@@ -48,4 +48,6 @@ ChangeLog
 
 # Editors
 *~
-.*.swp
+.*.swp
+.idea
+*.iml

translator/toscalib/elements/interfaces.py

@@ -14,6 +14,7 @@
 #    under the License.
 
 from translator.toscalib.elements.statefulentitytype import StatefulEntityType
+from translator.toscalib.functions import get_function
 
 SECTIONS = (LIFECYCLE, CONFIGURE) = \
            ('tosca.interfaces.node.Lifecycle',
@@ -23,17 +24,17 @@ SECTIONS = (LIFECYCLE, CONFIGURE) = \
 class InterfacesDef(StatefulEntityType):
     '''TOSCA built-in interfaces type.'''
 
-    def __init__(self, ntype, interfacetype,
+    def __init__(self, node_type, interfacetype,
-                 tpl_name=None, name=None, value=None):
+                 node_template=None, name=None, value=None):
-        self.nodetype = ntype
+        self.ntype = node_type
-        self.tpl_name = tpl_name
+        self.node_template = node_template
         self.type = interfacetype
         self.name = name
         self.value = value
         self.implementation = None
         self.input = None
         self.defs = {}
-        if ntype:
+        if node_type:
             self.defs = self.TOSCA_DEF[interfacetype]
         if value:
             if isinstance(self.value, dict):
@@ -41,10 +42,19 @@ class InterfacesDef(StatefulEntityType):
                     if i == 'implementation':
                         self.implementation = j
                     if i == 'input':
-                        self.input = j
+                        self.input = self._create_input_functions(j)
             else:
                 self.implementation = value
 
+    def _create_input_functions(self, raw_input):
+        """Creates input functions if necessary.
+        :param raw_input: Raw input as dict.
+        :return: Modified input dict containing template functions.
+        :rtype: dict
+        """
+        return dict((k, get_function(self.node_template, v))
+                    for (k, v) in raw_input.items())
+
     @property
     def lifecycle_ops(self):
         if self.defs:

translator/toscalib/functions.py

@@ -0,0 +1,111 @@
+#
+#    Licensed under the Apache License, Version 2.0 (the "License"); you may
+#    not use this file except in compliance with the License. You may obtain
+#    a copy of the License at
+#
+#         http://www.apache.org/licenses/LICENSE-2.0
+#
+#    Unless required by applicable law or agreed to in writing, software
+#    distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+#    WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+#    License for the specific language governing permissions and limitations
+#    under the License.
+
+
+import abc
+
+
+GET_PROPERTY = 'get_property'
+GET_REF_PROPERTY = 'get_ref_property'
+
+
+class Function(object):
+    """An abstract type for representing a Tosca template function."""
+
+    __metaclass__ = abc.ABCMeta
+
+    def __init__(self, node_template, func_name, args):
+        self.node_template = node_template
+        self.name = func_name
+        self.args = args
+        self.validate()
+
+    @abc.abstractmethod
+    def result(self):
+        """Invokes the function and returns its result
+
+        Some methods invocation may only be relevant on runtime (for example,
+        getting runtime properties) and therefore its the responsibility of
+        the orchestrator/translator to take care of such functions invocation.
+
+        :return: Function invocation result.
+        """
+        return {self.name: self.args}
+
+    def validate(self):
+        """Validates function arguments."""
+
+
+class GetRefProperty(Function):
+    """Get a property via a reference expressed in the requirements section.
+
+    Arguments:
+        - Requirement name.
+        - Capability name.
+        - Property to get.
+
+    Example:
+        get_ref_property: [ database_endpoint, database_endpoint, port ]
+    """
+
+    def validate(self):
+        if len(self.args) != 3:
+            raise ValueError(
+                'Expected arguments: requirement, capability, property')
+
+    def result(self):
+        requires = self.node_template.requirements
+        name = None
+        if requires:
+            requirement = self.args[0]
+            for r in requires:
+                for cap, node in r.items():
+                    if cap == requirement:
+                        name = node
+                        break
+            if name:
+                from translator.toscalib.nodetemplate import NodeTemplate
+                tpl = NodeTemplate(
+                    name, self.node_template.node_templates)
+                caps = tpl.capabilities
+                required_cap = self.args[1]
+                required_property = self.args[2]
+                for c in caps:
+                    if c.name == required_cap:
+                        return c.properties.get(required_property)
+
+
+function_mappings = {
+    GET_REF_PROPERTY: GetRefProperty
+}
+
+
+def get_function(node_template, raw_function):
+    """Gets a Function instance representing the provided template function.
+
+    If the format provided raw_function format is not relevant for template
+    functions or if the function name doesn't exist in function mapping the
+    method returns the provided raw_function.
+
+    :param node_template: The node template the function is specified for.
+    :param raw_function: The raw function as dict.
+    :return: Template function as Function instance or the raw_function if
+     parsing was unsuccessful.
+    """
+    if isinstance(raw_function, dict) and len(raw_function) == 1:
+        func_name = list(raw_function.keys())[0]
+        if func_name in function_mappings:
+            func = function_mappings[func_name]
+            func_args = list(raw_function.values())[0]
+            return func(node_template, func_name, func_args)
+    return raw_function

translator/toscalib/nodetemplate.py

@@ -78,14 +78,17 @@ class NodeTemplate(object):
     @property
     def interfaces(self):
         interfaces = []
-        ifaces = self.node_type.get_value(INTERFACES, self.node_template)
+        type_interfaces = self.node_type.get_value(INTERFACES,
-        if ifaces:
+                                                   self.node_template)
-            for i in ifaces:
+        if type_interfaces:
-                for name, value in ifaces.items():
+            for interface_type, value in type_interfaces.items():
-                    for ops, val in value.items():
+                for op, op_def in value.items():
-                        iface = InterfacesDef(None, name, self.name,
+                    iface = InterfacesDef(self.node_type,
-                                              ops, val)
+                                          interfacetype=interface_type,
-                        interfaces.append(iface)
+                                          node_template=self,
+                                          name=op,
+                                          value=op_def)
+                    interfaces.append(iface)
         return interfaces
 
     @property

translator/toscalib/tests/test_toscatpl.py

@@ -14,6 +14,7 @@
 #    under the License.
 
 import os
+from translator.toscalib.functions import GetRefProperty
 from translator.toscalib.tests.base import TestCase
 from translator.toscalib.tosca_template import ToscaTemplate
 
@@ -104,3 +105,36 @@ class ToscaTemplateTest(TestCase):
         self.assertEqual(
             ['website_url'],
             sorted([output.name for output in self.tosca.outputs]))
+
+    def test_interfaces(self):
+        wordpress_node = [
+            node for node in self.tosca.nodetemplates
+            if node.name == 'wordpress'][0]
+        interfaces = wordpress_node.interfaces
+        self.assertEqual(2, len(interfaces))
+        for interface in interfaces:
+            if interface.name == 'create':
+                self.assertEqual('tosca.interfaces.node.Lifecycle',
+                                 interface.type)
+                self.assertEqual('wordpress_install.sh',
+                                 interface.implementation)
+                self.assertIsNone(interface.input)
+            elif interface.name == 'configure':
+                self.assertEqual('tosca.interfaces.node.Lifecycle',
+                                 interface.type)
+                self.assertEqual('wordpress_configure.sh',
+                                 interface.implementation)
+                self.assertEqual(4, len(interface.input))
+                wp_db_port = interface.input['wp_db_port']
+                self.assertTrue(isinstance(wp_db_port, GetRefProperty))
+                self.assertEqual('get_ref_property', wp_db_port.name)
+                self.assertEqual(['database_endpoint',
+                                  'database_endpoint',
+                                  'port'],
+                                 wp_db_port.args)
+                result = wp_db_port.result()
+                self.assertEqual(1, len(result))
+                self.assertEqual('db_port', result['get_input'])
+            else:
+                raise AssertionError(
+                    'Unexpected interface: {0}'.format(interface.name))