1 files changed, 55 insertions, 0 deletions
diff --git a/src_py/hatter/backend.py b/src_py/hatter/backend.py
index 059c636..e89a867 100644
--- a/src_py/hatter/backend.py
+++ b/src_py/hatter/backend.py
@@ -1,12 +1,20 @@
 from pathlib import Path
+import typing
 
 from hat import aio
 
+from hatter import common
+
 
 async def create(db_path: Path
                  ) -> 'Backend':
     backend = Backend()
     backend._async_group = aio.Group()
+    backend._executor = aio.create_executor(1)
+
+    backend._db = await backend._executor(_ext_create, db_path)
+    backend.async_group.spawn(aio.call_on_cancel, backend._executor,
+                              _ext_close, backend._db)
 
     return backend
 
@@ -16,3 +24,50 @@ class Backend(aio.Resource):
     @property
     def async_group(self):
         return self._async_group
+
+    async def get_commits(self,
+                          repo: typing.Optional[str],
+                          statuses: typing.Optional[typing.Set[common.Status]],
+                          order: common.Order
+                          ) -> typing.List[common.Commit]:
+        return await self.async_group.spawn(
+            self._executor, _ext_get_commits, self._db, repo, statuses, order)
+
+    async def get_commit(self,
+                         repo: str,
+                         commit_hash: str
+                         ) -> typing.Optional[common.Commit]:
+        return await self.async_group.spawn(
+            self._executor, _ext_get_commit, self._db, repo, commit_hash)
+
+    async def update_commit(self, commit: common.Commit):
+        return await self._async_group.spawn(
+            self._executor, _ext_update_commit, self._db, commit)
+
+    async def remove_commit(self, commit: common.Commit):
+        return await self.async_group.spawn(
+            self._executor, _ext_remove_commit, self._db, commit)
+
+
+def _ext_create(db_path):
+    pass
+
+
+def _ext_close(db):
+    pass
+
+
+def _ext_get_commits(db, repo, statuses, order):
+    return []
+
+
+def _ext_get_commit(db, repo, commit_hash):
+    pass
+
+
+def _ext_update_commit(db, commit):
+    pass
+
+
+def _ext_remove_commit(db, commit):
+    pass