Fix small errors like unhandled exceptions etc.

gns3server/controller/__init__.py

@@ -66,9 +66,7 @@ class Controller:
 
     def load_appliances(self):
         self._appliance_templates = {}
-        for directory, builtin in (
-            (get_resource('appliances'), True,), (self.appliances_path(), False,)
-        ):
+        for directory, builtin in ((get_resource('appliances'), True,), (self.appliances_path(), False,)):
             if directory and os.path.isdir(directory):
                 for file in os.listdir(directory):
                     if not file.endswith('.gns3a') and not file.endswith('.gns3appliance'):
@@ -200,7 +198,7 @@ class Controller:
         for c in computes:
             try:
                 yield from self.add_compute(**c)
-            except (aiohttp.web.HTTPConflict, KeyError):
+            except (aiohttp.web.HTTPError, KeyError):
                 pass  # Skip not available servers at loading
         yield from self.load_projects()
         try:

gns3server/controller/node.py

@@ -175,7 +175,7 @@ class Node:
         if not os.path.isabs(path):
             path = os.path.join(self.project.controller.configs_path(), path)
         try:
-            with open(path) as f:
+            with open(path, encoding="utf-8") as f:
                 return f.read()
         except OSError:
             return None

gns3server/controller/project.py

@@ -843,7 +843,7 @@ class Project:
                 link = yield from self.add_link(link_id=link_data["link_id"])
                 if "filters" in link_data:
                     yield from link.update_filters(link_data["filters"])
-                for node_link in link_data["nodes"]:
+                for node_link in link_data.get("nodes", []):
                     node = self.get_node(node_link["node_id"])
                     port = node.get_port(node_link["adapter_number"], node_link["port_number"])
                     if port is None:

gns3server/controller/symbols.py

@@ -22,6 +22,9 @@ from ..utils.get_resource import get_resource
 from ..utils.picture import get_size
 from ..config import Config
 
+import logging
+log = logging.getLogger(__name__)
+
 
 class Symbols:
     """
@@ -72,19 +75,25 @@ class Symbols:
     def symbols_path(self):
         directory = os.path.expanduser(Config.instance().get_section_config("Server").get("symbols_path", "~/GNS3/symbols"))
         if directory:
-            os.makedirs(directory, exist_ok=True)
+            try:
+                os.makedirs(directory, exist_ok=True)
+            except OSError as e:
+                log.error("Could not create symbol directory '{}': {}".format(directory, e))
+                return None
         return directory
 
     def get_path(self, symbol_id):
         try:
             return self._symbols_path[symbol_id]
-        # Symbol not found refresh cache
+        # Symbol not found, let's refresh the cache
         except KeyError:
-            self.list()
             try:
+                self.list()
                 return self._symbols_path[symbol_id]
-            except KeyError:
-                return self._symbols_path[":/symbols/computer.svg"]
+            except (OSError, KeyError):
+                log.warning("Could not retrieve symbol '{}'".format(symbol_id))
+                symbols_path = self._symbols_path
+                return symbols_path[":/symbols/computer.svg"]
 
     def get_size(self, symbol_id):
         try:

gns3server/controller/topology.py

@@ -409,7 +409,7 @@ def _convert_1_3_later(topo, topo_path):
             symbol = old_node.get("symbol", ":/symbols/computer.svg")
             old_node["ports"] = _create_cloud(node, old_node, symbol)
         else:
-            raise NotImplementedError("Conversion of {} is not supported".format(old_node["type"]))
+            raise aiohttp.web.HTTPConflict(text="Conversion of {} is not supported".format(old_node["type"]))
 
         for prop in old_node.get("properties", {}):
             if prop not in ["console", "name", "console_type", "console_host", "use_ubridge"]:
@@ -608,13 +608,13 @@ def _create_cloud(node, old_node, icon):
         elif old_port["name"].startswith("nio_nat"):
             continue
         else:
-            raise NotImplementedError("The conversion of cloud with {} is not supported".format(old_port["name"]))
+            raise aiohttp.web.HTTPConflict(text="The conversion of cloud with {} is not supported".format(old_port["name"]))
 
         if port_type == "udp":
             try:
                 _, lport, rhost, rport = old_port["name"].split(":")
             except ValueError:
-                raise NotImplementedError("UDP tunnel using IPV6 is not supported in cloud")
+                raise aiohttp.web.HTTPConflict(text="UDP tunnel using IPV6 is not supported in cloud")
             port = {
                 "name": "UDP tunnel {}".format(len(ports) + 1),
                 "port_number": len(ports) + 1,
@@ -645,7 +645,7 @@ def _convert_snapshots(topo_dir):
     old_snapshots_dir = os.path.join(topo_dir, "project-files", "snapshots")
     if os.path.exists(old_snapshots_dir):
         new_snapshots_dir = os.path.join(topo_dir, "snapshots")
-        os.makedirs(new_snapshots_dir)
+        os.makedirs(new_snapshots_dir, exist_ok=True)
 
         for snapshot in os.listdir(old_snapshots_dir):
             snapshot_dir = os.path.join(old_snapshots_dir, snapshot)