1 files changed, 85 insertions, 0 deletions
diff --git a/ick2/store.py b/ick2/store.py
new file mode 100644
index 0000000..2d93daf
--- /dev/null
+++ b/ick2/store.py
@@ -0,0 +1,85 @@
+# Copyright (C) 2019  Lars Wirzenius
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU Affero General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU Affero General Public License for more details.
+#
+# You should have received a copy of the GNU Affero General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+
+import copy
+import uuid
+
+
+import ick2
+
+
+class StoreInterface:  # pragma: no cover
+
+    def create(self, token, obj):
+        raise NotImplementedError()
+
+    def update(self, token, rid, obj, revision):
+        raise NotImplementedError()
+
+    def show(self, token, rid):
+        raise NotImplementedError()
+
+    def delete(self, token, rid):
+        raise NotImplementedError()
+
+    def search(self, token, cond):
+        raise NotImplementedError()
+
+
+class MemoryStore(StoreInterface):
+
+    def __init__(self):
+        self._objs = {}
+
+    def search(self, token, cond):
+        return list(self._objs.keys())
+
+    def _new_id(self):
+        return str(uuid.uuid4())
+
+    def _set(self, rid, rev, obj):
+        self._objs[rid] = (rev, copy.deepcopy(obj))
+
+    def create(self, token, obj):
+        rid = self._new_id()
+        rev = self._new_id()
+        self._set(rid, rev, obj)
+        return rid, rev
+
+    def show(self, token, rid):
+        if rid not in self._objs:
+            raise ick2.NotFound('unknown.type', rid)
+        rev, obj = self._objs[rid]
+        return copy.deepcopy(obj), rev
+
+    def update(self, token, rid, obj, revision):
+        old_obj, old_rev = self.show(token, rid)
+        if old_rev != revision:
+            raise Conflict(rid, old_rev, revision)
+        new_rev = self._new_id()
+        self._set(rid, new_rev, obj)
+        return new_rev
+
+    def delete(self, token, rid):
+        del self._objs[rid]
+
+
+class Conflict(Exception):
+
+    def __init__(self, rid, expected, got):
+        super().__init__(
+            'Update conflict for {}: expected revision {}, got {}'.format(
+                rid, expected, got))