Update vApp to create VMs from template

pyvcloud/vcd/vapp.py

@@ -36,6 +36,7 @@
 from pyvcloud.vcd.exceptions import InvalidStateException
 from pyvcloud.vcd.exceptions import OperationNotSupportedException
 from pyvcloud.vcd.metadata import Metadata
+from pyvcloud.vcd.org import Org
 from pyvcloud.vcd.utils import cidr_to_netmask
 from pyvcloud.vcd.utils import generate_compute_policy_tags
 from pyvcloud.vcd.vdc import VDC
@@ -1031,6 +1032,101 @@ def add_vms(self,
             self.resource, RelationType.RECOMPOSE,
             EntityType.RECOMPOSE_VAPP_PARAMS.value, params)
 
+    def get_template(self, catalog, template):
+        """Returns the template resource from the provided catalog name
+        and vapp template name
+        """
+        org_resource = self.client.get_org()
+        org = Org(self.client, resource=org_resource)
+        catalog_item = org.get_catalog_item(catalog, template)
+        template_vapp_resource = self.client.get_resource(
+            catalog_item.Entity.get('href'))
+        return template_vapp_resource
+
+    def create_vm_from_template(self,
+                                catalog,
+                                vapp_template,
+                                vm_template,
+                                isAdmin=False,
+                                name=None,
+                                hostname=None,
+                                password=None,
+                                password_auto=None,
+                                password_reset=None,
+                                cust_script=None,
+                                network=None,
+                                disk_size=None,
+                                storage_profile=None,
+                                sizing_policy_href=None,
+                                placement_policy_href=None,
+                                ip_allocation_mode='DHCP'):
+        """Creates a vm from a template or based on an existing VM from a
+        different vapp and recompose the vapp to add the new vm.
+
+        This method is similar to add_vms but,
+        instead the template resource, you provide a vapp name or vapp template
+            name to create the new VM based on an existing vm from the vapp.
+
+        :param str catalog: (required) catalog name cointaining vapp template.
+        :param str vapp_template: (required) source vApp template name.
+        :param str vm_template: (required) source vm template name.
+        :param str bame: (optional) new vm name.
+        :param str hostname: (optional) new guest hostname.
+        :param str password: (optional) the administrator password of the vm.
+        :param str password_auto: (bool): (optional) auto generate
+            administrator password.
+        :param str password_reset: (bool): (optional) True, if the
+            administrator password for this vm must be reset after first use.
+        :param str cust_script: (optional) script to run on guest
+            customization.
+        :param str network: (optional) name of the vApp network to connect.
+            If omitted, the vm won't be connected to any network.
+        :param str storage_profile: (optional) the name of the storage
+            profile to be used for this vm.
+        :param str sizing_policy_href: (optional) sizing policy used for
+            creating the VM.
+        :param str placement_policy_href: (optional) placement policy used
+            for creating the VM.
+        :param str ip_allocation_mode: (optional) the allocation mode for ip.
+            Default is for DHCP.
+
+        :return: an object containing EntityType.VAPP XML data representing the
+            updated vApp.
+
+        :rtype: lxml.objectify.ObjectifiedElement
+        """
+        try:
+            template_vapp_resource = self.get_template(catalog, vapp_template)
+        except EntityNotFoundException:
+            print("Template vapp {0} couldn't be instantiated "
+                  "from {1}".format(vapp_template, catalog))
+
+        vm_cfg = {
+            "vapp": template_vapp_resource,
+            "source_vm_name": vm_template,
+        }
+
+        if name:
+            vm_cfg["target_vm_name"] = name
+        if network:
+            vm_cfg["network"] = network
+            if ip_allocation_mode:
+                vm_cfg["ip_allocation_mode"] = ip_allocation_mode
+        if disk_size:
+            vm_cfg["disk_size"] = disk_size
+        if password:
+            vm_cfg["password"] = password
+        if password_auto:
+            vm_cfg["password_auto"] = password_auto
+        if password_reset:
+            vm_cfg["password_reset"] = password_reset
+        if cust_script:
+            vm_cfg["cust_script"] = cust_script
+        if hostname:
+            vm_cfg["hostname"] = hostname
+
+        return self.add_vms([vm_cfg])
+
     def delete_vms(self, names):
         """Recompose the vApp and delete vms.