fix: validate VM names

fixes: https://gitea.gna.org/Hostea/dashboard/issues/51

accounts/tests.py

@@ -77,7 +77,9 @@ class LoginTest(TestCase):
         Tests if login template renders
         """
         resp = self.client.get(reverse("accounts.login"))
-        self.assertEqual(b"A free forge ecosystem for free developers" in resp.content, True)
+        self.assertEqual(
+            b"A free forge ecosystem for free developers" in resp.content, True
+        )
 
     def test_login_works(self):
         """
@@ -234,7 +236,9 @@ class RegistrationTest(TestCase):
         Tests if register template renders
         """
         resp = self.client.get(reverse("accounts.register"))
-        self.assertEqual(b"A free forge ecosystem for free developers." in resp.content, True)
+        self.assertEqual(
+            b"A free forge ecosystem for free developers." in resp.content, True
+        )
 
     def test_register_works(self):
         """

dash/utils.py

@@ -23,6 +23,8 @@ from .models import Instance, InstanceConfiguration
 @unique
 class VmErrors(Enum):
     NAME_EXISTS = "Instance name exists, please try again with a different name"
+    ILLEGAL_NAME = "Only alphanumeric characters are allowed in instance name"
+    NAME_TOO_LONG = "Instance name must be less than 20 characters"
     NO_CONFIG = "Configuration doesn't exist, please try again."
 
     def __str__(self) -> str:
@@ -46,6 +48,11 @@ def create_instance(vm_name: str, configuration_name: str, user: User) -> Instan
     Create instance view
     """
 
+    if len(vm_name) > 20:
+        raise VmException(code=VmErrors.NAME_TOO_LONG)
+    if not str.isalnum(vm_name):
+        raise VmException(code=VmErrors.ILLEGAL_NAME)
+
     if Instance.objects.filter(name=vm_name).exists():
         raise VmException(code=VmErrors.NAME_EXISTS)
 

dash/views.py

@@ -89,10 +89,7 @@ def create_instance(request):
         return redirect(reverse("billing.invoice.generate", args=(instance.name,)))
     except VmException as e:
         ctx = get_ctx()
-        if e.code == VmErrors.NAME_EXISTS:
-            reason = ("Instance name exists, please try again with a different name",)
-        elif e.code == VmErrors.NO_CONFIG:
-            reason = "Configuration doesn't exist, please try again."
+        reason = e.error
 
         ctx["error"] = {
             "title": "Can't create instance",