1 files changed, 118 insertions, 0 deletions
diff --git a/azure/aria/aria-extension-cloudify/src/aria/aria/orchestrator/workflows/core/graph_compiler.py b/azure/aria/aria-extension-cloudify/src/aria/aria/orchestrator/workflows/core/graph_compiler.py
new file mode 100644
index 0000000..81543d5
--- /dev/null
+++ b/azure/aria/aria-extension-cloudify/src/aria/aria/orchestrator/workflows/core/graph_compiler.py
@@ -0,0 +1,118 @@
+# Licensed to the Apache Software Foundation (ASF) under one or more
+# contributor license agreements.  See the NOTICE file distributed with
+# this work for additional information regarding copyright ownership.
+# The ASF licenses this file to You 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.
+
+
+from ....modeling import models
+from .. import executor, api
+
+
+class GraphCompiler(object):
+    def __init__(self, ctx, default_executor):
+        self._ctx = ctx
+        self._default_executor = default_executor
+        self._stub_executor = executor.base.StubTaskExecutor
+        self._model_to_api_id = {}
+
+    def compile(self,
+                task_graph,
+                start_stub_type=models.Task.START_WORKFLOW,
+                end_stub_type=models.Task.END_WORKFLOW,
+                depends_on=()):
+        """
+        Translates the user graph to the execution graph
+        :param task_graph: The user's graph
+        :param start_stub_type: internal use
+        :param end_stub_type: internal use
+        :param depends_on: internal use
+        """
+        depends_on = list(depends_on)
+
+        # Insert start marker
+        start_task = self._create_stub_task(
+            start_stub_type, depends_on, self._start_graph_suffix(task_graph.id), task_graph.name,
+        )
+
+        for task in task_graph.topological_order(reverse=True):
+            dependencies = \
+                (self._get_tasks_from_dependencies(task_graph.get_dependencies(task))
+                 or [start_task])
+
+            if isinstance(task, api.task.OperationTask):
+                self._create_operation_task(task, dependencies)
+
+            elif isinstance(task, api.task.WorkflowTask):
+                # Build the graph recursively while adding start and end markers
+                self.compile(
+                    task, models.Task.START_SUBWROFKLOW, models.Task.END_SUBWORKFLOW, dependencies
+                )
+            elif isinstance(task, api.task.StubTask):
+                self._create_stub_task(models.Task.STUB, dependencies, task.id)
+            else:
+                raise RuntimeError('Undefined state')
+
+        # Insert end marker
+        self._create_stub_task(
+            end_stub_type,
+            self._get_non_dependent_tasks(self._ctx.execution) or [start_task],
+            self._end_graph_suffix(task_graph.id),
+            task_graph.name
+        )
+
+    def _create_stub_task(self, stub_type, dependencies, api_id, name=None):
+        model_task = models.Task(
+            name=name,
+            dependencies=dependencies,
+            execution=self._ctx.execution,
+            _executor=self._stub_executor,
+            _stub_type=stub_type)
+        self._ctx.model.task.put(model_task)
+        self._model_to_api_id[model_task.id] = api_id
+        return model_task
+
+    def _create_operation_task(self, api_task, dependencies):
+        model_task = models.Task.from_api_task(
+            api_task, self._default_executor, dependencies=dependencies)
+        self._ctx.model.task.put(model_task)
+        self._model_to_api_id[model_task.id] = api_task.id
+        return model_task
+
+    @staticmethod
+    def _start_graph_suffix(api_id):
+        return '{0}-Start'.format(api_id)
+
+    @staticmethod
+    def _end_graph_suffix(api_id):
+        return '{0}-End'.format(api_id)
+
+    @staticmethod
+    def _get_non_dependent_tasks(execution):
+        tasks_with_dependencies = set()
+        for task in execution.tasks:
+            tasks_with_dependencies.update(task.dependencies)
+        return list(set(execution.tasks) - set(tasks_with_dependencies))
+
+    def _get_tasks_from_dependencies(self, dependencies):
+        """
+        Returns task list from dependencies.
+        """
+        tasks = []
+        for dependency in dependencies:
+            if isinstance(dependency, (api.task.StubTask, api.task.OperationTask)):
+                dependency_name = dependency.id
+            else:
+                dependency_name = self._end_graph_suffix(dependency.id)
+            tasks.extend(task for task in self._ctx.execution.tasks
+                         if self._model_to_api_id.get(task.id, None) == dependency_name)
+        return tasks