Reorganize how appliance creation is validated against JSON schemas.

This allows for clearer error messages when validation fails.

gns3server/controller/__init__.py

@@ -23,6 +23,7 @@ import socket
 import shutil
 import asyncio
 import aiohttp
+import jsonschema
 
 from ..config import Config
 from .project import Project
@@ -144,10 +145,9 @@ class Controller:
             appliance_id = settings.setdefault("appliance_id", str(uuid.uuid4()))
         try:
             appliance = Appliance(appliance_id, settings)
-            appliance.__json__()  # Check if loaded without error
-        except KeyError as e:
-            # appliance settings is not complete
-            raise aiohttp.web.HTTPConflict(text="Cannot create new appliance: key '{}' is missing for appliance ID '{}'".format(e, appliance_id))
+        except jsonschema.ValidationError as e:
+            message = "JSON schema error adding appliance with JSON data '{}': {}".format(settings, e.message)
+            raise aiohttp.web.HTTPBadRequest(text=message)
         self._appliances[appliance.id] = appliance
         self.save()
         self.notification.controller_emit("appliance.created", appliance.__json__())
@@ -327,11 +327,10 @@ class Controller:
             for appliance_settings in controller_settings["appliances"]:
                 try:
                     appliance = Appliance(appliance_settings["appliance_id"], appliance_settings)
-                    appliance.__json__()  # Check if loaded without error
                     self._appliances[appliance.id] = appliance
-                except KeyError as e:
-                    # appliance data is not complete (missing name or type)
-                    log.warning("Cannot load appliance template {} ('{}'): missing key {}".format(appliance_settings["appliance_id"], appliance_settings.get("name", "unknown"), e))
+                except jsonschema.ValidationError as e:
+                    message = "Cannot load appliance with JSON data '{}': {}".format(appliance_settings, e.message)
+                    log.warning(message)
                     continue
 
         # load GNS3 VM settings

gns3server/controller/appliance.py

@@ -17,6 +17,56 @@
 
 import copy
 import uuid
+import json
+import jsonschema
+
+from gns3server.schemas.cloud_appliance import CLOUD_APPLIANCE_OBJECT_SCHEMA
+from gns3server.schemas.ethernet_switch_appliance import ETHERNET_SWITCH_APPLIANCE_OBJECT_SCHEMA
+from gns3server.schemas.ethernet_hub_appliance import ETHERNET_HUB_APPLIANCE_OBJECT_SCHEMA
+from gns3server.schemas.docker_appliance import DOCKER_APPLIANCE_OBJECT_SCHEMA
+from gns3server.schemas.vpcs_appliance import VPCS_APPLIANCE_OBJECT_SCHEMA
+from gns3server.schemas.traceng_appliance import TRACENG_APPLIANCE_OBJECT_SCHEMA
+from gns3server.schemas.virtualbox_appliance import VIRTUALBOX_APPLIANCE_OBJECT_SCHEMA
+from gns3server.schemas.vmware_appliance import VMWARE_APPLIANCE_OBJECT_SCHEMA
+from gns3server.schemas.iou_appliance import IOU_APPLIANCE_OBJECT_SCHEMA
+from gns3server.schemas.qemu_appliance import QEMU_APPLIANCE_OBJECT_SCHEMA
+
+from gns3server.schemas.dynamips_appliance import (
+    DYNAMIPS_APPLIANCE_OBJECT_SCHEMA,
+    C7200_DYNAMIPS_APPLIANCE_OBJECT_SCHEMA,
+    C3745_DYNAMIPS_APPLIANCE_OBJECT_SCHEMA,
+    C3725_DYNAMIPS_APPLIANCE_OBJECT_SCHEMA,
+    C3600_DYNAMIPS_APPLIANCE_OBJECT_SCHEMA,
+    C2691_DYNAMIPS_APPLIANCE_OBJECT_SCHEMA,
+    C2600_DYNAMIPS_APPLIANCE_OBJECT_SCHEMA,
+    C1700_DYNAMIPS_APPLIANCE_OBJECT_SCHEMA
+)
+
+import logging
+log = logging.getLogger(__name__)
+
+
+# Add default values for missing entries in a request, largely taken from jsonschema documentation example
+# https://python-jsonschema.readthedocs.io/en/latest/faq/#why-doesn-t-my-schema-s-default-property-set-the-default-on-my-instance
+def extend_with_default(validator_class):
+
+    validate_properties = validator_class.VALIDATORS["properties"]
+    def set_defaults(validator, properties, instance, schema):
+        if jsonschema.Draft4Validator(schema).is_valid(instance):
+            # only add default for the matching sub-schema (e.g. when using 'oneOf')
+            for property, subschema in properties.items():
+                if "default" in subschema:
+                    instance.setdefault(property, subschema["default"])
+
+        for error in validate_properties(validator, properties, instance, schema,):
+            yield error
+
+    return jsonschema.validators.extend(
+        validator_class, {"properties" : set_defaults},
+    )
+
+
+ValidatorWithDefaults = extend_with_default(jsonschema.Draft4Validator)
 
 ID_TO_CATEGORY = {
     3: "firewall",
@@ -25,6 +75,30 @@ ID_TO_CATEGORY = {
     0: "router"
 }
 
+APPLIANCE_TYPE_TO_SHEMA = {
+    "cloud": CLOUD_APPLIANCE_OBJECT_SCHEMA,
+    "ethernet_hub": ETHERNET_HUB_APPLIANCE_OBJECT_SCHEMA,
+    "ethernet_switch": ETHERNET_SWITCH_APPLIANCE_OBJECT_SCHEMA,
+    "docker": DOCKER_APPLIANCE_OBJECT_SCHEMA,
+    "dynamips": DYNAMIPS_APPLIANCE_OBJECT_SCHEMA,
+    "vpcs": VPCS_APPLIANCE_OBJECT_SCHEMA,
+    "traceng": TRACENG_APPLIANCE_OBJECT_SCHEMA,
+    "virtualbox": VIRTUALBOX_APPLIANCE_OBJECT_SCHEMA,
+    "vmware": VMWARE_APPLIANCE_OBJECT_SCHEMA,
+    "iou": IOU_APPLIANCE_OBJECT_SCHEMA,
+    "qemu": QEMU_APPLIANCE_OBJECT_SCHEMA
+}
+
+DYNAMIPS_PLATFORM_TO_SHEMA = {
+    "c7200": C7200_DYNAMIPS_APPLIANCE_OBJECT_SCHEMA,
+    "c3745": C3745_DYNAMIPS_APPLIANCE_OBJECT_SCHEMA,
+    "c3725": C3725_DYNAMIPS_APPLIANCE_OBJECT_SCHEMA,
+    "c3600": C3600_DYNAMIPS_APPLIANCE_OBJECT_SCHEMA,
+    "c2691": C2691_DYNAMIPS_APPLIANCE_OBJECT_SCHEMA,
+    "c2600": C2600_DYNAMIPS_APPLIANCE_OBJECT_SCHEMA,
+    "c1700": C1700_DYNAMIPS_APPLIANCE_OBJECT_SCHEMA
+}
+
 
 class Appliance:
 
@@ -66,6 +140,13 @@ class Appliance:
 
         self._builtin = builtin
 
+        if builtin is False:
+            self.validate_and_apply_defaults(APPLIANCE_TYPE_TO_SHEMA[self.appliance_type])
+
+            if self.appliance_type == "dynamips":
+                # special case for Dynamips to cover all platform types that contain specific settings
+                self.validate_and_apply_defaults(DYNAMIPS_PLATFORM_TO_SHEMA[self._settings["platform"]])
+
     @property
     def id(self):
         return self._id
@@ -102,6 +183,17 @@ class Appliance:
         controller.notification.controller_emit("appliance.updated", self.__json__())
         controller.save()
 
+    def validate_and_apply_defaults(self, schema):
+
+        validator = ValidatorWithDefaults(schema)
+        try:
+            validator.validate(self.__json__())
+        except jsonschema.ValidationError as e:
+            message = "JSON schema error {}".format(e.message)
+            log.error(message)
+            log.debug("Input schema: {}".format(json.dumps(schema)))
+            raise
+
     def __json__(self):
         """
         Appliance settings.
@@ -109,8 +201,6 @@ class Appliance:
 
         settings = self._settings
         settings.update({"appliance_id": self._id,
-                         "default_name_format": settings.get("default_name_format", "{name}-{0}"),
-                         "symbol": settings.get("symbol", ":/symbols/computer.svg"),
                          "builtin": self.builtin})
 
         if not self.builtin: