Added CrudBackend abstract class defining generic CRUD API

ipalib/crud.py

@@ -21,7 +21,7 @@
 Base classes for standard CRUD operations.
 """
 
-import frontend, errors
+import backend, frontend, errors
 
 
 class Add(frontend.Method):
@@ -63,3 +63,77 @@ class Find(frontend.Method):
     def get_options(self):
         for param in self.obj.params_minus_pk():
             yield param.__clone__(required=False)
+
+
+class CrudBackend(backend.Backend):
+    """
+    Base class defining generic CRUD backend API.
+    """
+
+    def create(self, *kw):
+        """
+        Create a new entry.
+
+        This method should take key word arguments representing the
+        attributes the created entry will have.
+
+        If this methods constructs the primary_key internally, it should raise
+        an exception if the primary_key was passed.  Likewise, if this method
+        requires the primary_key to be passed in from the caller, it should
+        raise an exception if the primary key was *not* passed.
+
+        This method should return a dict of the exact entry as it was created
+        in the backing store, including any automatically created attributes.
+        """
+        raise NotImplementedError('%s.create()' % self.name)
+
+    def retrieve(self, primary_key):
+        """
+        Retrieve an existing entry.
+
+        This method should take a single argument, the primary_key of the
+        entry in question.
+
+        If such an entry exists, this method should return a dict
+        representing that entry.  If no such entry exists, this method
+        should return None.
+        """
+        raise NotImplementedError('%s.retrieve()' % self.name)
+
+    def update(self, primary_key, *kw):
+        """
+        Update an existing entry.
+
+        This method should take one required argument, the primary_key of the
+        entry to modify, plus optional keyword arguments for each of the
+        attributes being updated.
+
+        This method should return a dict representing the entry as it now
+        exists in the backing store.  If no such entry exists, this method
+        should return None.
+        """
+        raise NotImplementedError('%s.update()' % self.name)
+
+    def delete(self, primary_key):
+        """
+        Delete an existing entry.
+
+        This method should take one required argument, the primary_key of the
+        entry to delete.
+        """
+        raise NotImplementedError('%s.delete()' % self.name)
+
+    def search(self, **kw):
+        """
+        Return entries matching specific criteria.
+
+        This method should take keyword arguments representing the search
+        criteria.  If a key is the name of an entry attribute, the value
+        should be treated as a filter on that attribute.  The meaning of
+        keys outside this namespace is left to the implementation.
+
+        This method should return and iterable containing the matched
+        entries, where each entry is a dict.  If no entries are matched,
+        this method should return an empty iterable.
+        """
+        raise NotImplementedError('%s.search()' % self.name)

tests/test_ipalib/test_crud.py

@@ -189,3 +189,54 @@ class test_Find(CrudChecker):
             ['givenname', 'sn', 'initials']
         for param in api.Method.user_verb.options():
             assert param.required is False
+
+
+class test_CrudBackend(ClassChecker):
+    """
+    Test the `ipalib.crud.CrudBackend` class.
+    """
+
+    _cls = crud.CrudBackend
+
+    def get_subcls(self):
+        class ldap(self.cls):
+            pass
+        return ldap
+
+    def check_method(self, name, *args):
+        o = self.cls()
+        e = raises(NotImplementedError, getattr(o, name), *args)
+        assert str(e) == 'CrudBackend.%s()' % name
+        sub = self.subcls()
+        e = raises(NotImplementedError, getattr(sub, name), *args)
+        assert str(e) == 'ldap.%s()' % name
+
+    def test_create(self):
+        """
+        Test the `ipalib.crud.CrudBackend.create` method.
+        """
+        self.check_method('create')
+
+    def test_retrieve(self):
+        """
+        Test the `ipalib.crud.CrudBackend.retrieve` method.
+        """
+        self.check_method('retrieve', 'primary key')
+
+    def test_update(self):
+        """
+        Test the `ipalib.crud.CrudBackend.update` method.
+        """
+        self.check_method('update', 'primary key')
+
+    def test_delete(self):
+        """
+        Test the `ipalib.crud.CrudBackend.delete` method.
+        """
+        self.check_method('delete', 'primary key')
+
+    def test_search(self):
+        """
+        Test the `ipalib.crud.CrudBackend.search` method.
+        """
+        self.check_method('search')