changed interface to --seed a little to take a migration to stop at a…

…s opposed to a list of migrations to seed

nashvegas/management/commands/upgradedb.py

@@ -8,7 +8,7 @@
 from django.db.models import get_model
 from django.conf import settings
 from django.core.management import call_command
-from django.core.management.base import BaseCommand
+from django.core.management.base import BaseCommand, CommandError
 from django.core.management.sql import emit_post_sync_signal
 
 from nashvegas.models import Migration
@@ -18,6 +18,10 @@
 sys.path.append("migrations")
 
 
+class MigrationError(Exception):
+    pass
+
+
 class Command(BaseCommand):
 
     option_list = BaseCommand.option_list + (
@@ -44,7 +48,10 @@ class Command(BaseCommand):
                 help="The path to the database migration scripts."))
     help = "Upgrade database."
 
-    def _filter_down(self):
+    def _filter_down(self, stop_at=None):
+
+        if stop_at is None:
+            stop_at = float("inf")
 
         applied = []
         to_execute = []
@@ -61,11 +68,16 @@ def _filter_down(self):
             applied.sort()
 
             for script in in_directory:
-                if os.path.splitext(script)[-1] in [".sql", ".py"]:
-                    scripts_in_directory.append(script)
+                name, ext = os.path.splitext(script)
+                try:
+                    number = int(name.split("_")[0])
+                except ValueError:
+                    raise MigrationError("Invalid migration file prefix (must begin with a number)")
+                if ext in [".sql", ".py"]:
+                    scripts_in_directory.append((number, script))
 
-            for script in scripts_in_directory:
-                if script not in applied:
+            for number, script in scripts_in_directory:
+                if script not in applied and number < stop_at:
                     to_execute.append(script)
         except OSError, e:
             print str(e)
@@ -183,10 +195,13 @@ def execute_migrations(self):
             database=self.db
         )
 
-    def seed_migrations(self):
-        migrations = [os.path.join(self.path, m) for m in self._filter_down()]
-        if len(self.args) > 0:
-            migrations = [arg for arg in self.args if not arg.endswith(".pyc")]
+    def seed_migrations(self, stop_at=None):
+        # @@@ the command-line interface needs to be re-thinked
+        try:
+            stop_at = int(self.args[0])
+        except ValueError:
+            raise CommandError("Invalid --seed migration")
+        migrations = [os.path.join(self.path, m) for m in self._filter_down(stop_at=stop_at)]
         for migration in migrations:
             m, created = Migration.objects.get_or_create(
                 migration_label=os.path.basename(migration),