Merge pull request #491 from grycap/devel

Fix #490

IM/connectors/OpenStack.py

@@ -147,6 +147,51 @@ def get_driver(self, auth_data):
             self.driver = driver
             return driver
 
+    def get_instance_type(self, sizes, radl):
+        """
+        Get the name of the instance type to launch to LibCloud
+
+        Arguments:
+           - size(list of :py:class: `libcloud.compute.base.NodeSize`): List of sizes on a provider
+           - radl(str): RADL document with the requirements of the VM to get the instance type
+        Returns: a :py:class:`libcloud.compute.base.NodeSize` with the instance type to launch
+        """
+        instance_type_name = radl.getValue('instance_type')
+
+        cpu = 1
+        cpu_op = ">="
+        if radl.getFeature('cpu.count'):
+            cpu = radl.getValue('cpu.count')
+            cpu_op = radl.getFeature('cpu.count').getLogOperator()
+
+        memory = 1
+        memory_op = ">="
+        if radl.getFeature('memory.size'):
+            memory = radl.getFeature('memory.size').getValue('M')
+            memory_op = radl.getFeature('memory.size').getLogOperator()
+        disk_free = 0
+        disk_free_op = ">="
+        if radl.getValue('disk.0.free_size'):
+            disk_free = radl.getFeature('disk.0.free_size').getValue('G')
+            disk_free_op = radl.getFeature('memory.size').getLogOperator()
+
+        res = None
+        for size in sizes:
+            # get the node size with the lowest price and memory (in the case
+            # of the price is not set)
+            if res is None or (size.price <= res.price and size.ram <= res.ram):
+                str_compare = "size.ram " + memory_op + " memory"
+                str_compare += " and size.vcpus " + cpu_op + " cpu "
+                str_compare += " and size.disk " + disk_free_op + " disk_free"
+                if eval(str_compare):
+                    if not instance_type_name or size.name == instance_type_name:
+                        res = size
+
+        if res is None:
+            self.log_error("No compatible size found")
+
+        return res
+
     def concreteSystem(self, radl_system, auth_data):
         image_urls = radl_system.getValue("disk.0.image.url")
         if not image_urls: