[refactor] CouchDocument is now ServerDocument

As SoledadBackend is intended to be database agnostic, a new generic
document is now used instead of the old one made for CouchDB. The only
attribute that really relates to couch was couch_rev, removed on this
commit as it can be set on CouchDatabase implementation when needed.

4 files changed, 41 insertions, 57 deletions

diff --git a/common/src/leap/soledad/common/backend.py b/common/src/leap/soledad/common/backend.py
index cb37b4ac..1cbf3d57 100644
--- a/common/src/leap/soledad/common/backend.py
+++ b/common/src/leap/soledad/common/backend.py
@@ -29,7 +29,7 @@ from u1db.errors import (
 )
 from u1db.backends import CommonBackend
 from u1db.backends import CommonSyncTarget
-from leap.soledad.common.document import CouchDocument
+from leap.soledad.common.document import ServerDocument
 
 
 class SoledadBackend(CommonBackend):
@@ -48,7 +48,7 @@ class SoledadBackend(CommonBackend):
         :type replica_uid: str
         """
         # save params
-        self._factory = CouchDocument
+        self._factory = ServerDocument
         self._real_replica_uid = None
         self._cache = None
         self._dbname = database._dbname
@@ -83,7 +83,7 @@ class SoledadBackend(CommonBackend):
 
     def delete_database(self):
         """
-        Delete a U1DB CouchDB database.
+        Delete a U1DB database.
         """
         self._database.delete_database()
 
@@ -221,7 +221,7 @@ class SoledadBackend(CommonBackend):
         :type check_for_conflicts: bool
 
         :return: The document.
-        :rtype: CouchDocument
+        :rtype: ServerDocument
         """
         return self._database._get_doc(doc_id, check_for_conflicts)
 
@@ -237,7 +237,7 @@ class SoledadBackend(CommonBackend):
         :type include_deleted: bool
 
         :return: A document object.
-        :rtype: CouchDocument.
+        :rtype: ServerDocument.
         """
         doc = self._get_doc(doc_id, check_for_conflicts=True)
         if doc is None:
@@ -255,25 +255,25 @@ class SoledadBackend(CommonBackend):
                                 documents will not be included in the results.
         :type include_deleted: bool
 
-        :return: (generation, [CouchDocument])
+        :return: (generation, [ServerDocument])
             The current generation of the database, followed by a list of all
             the documents in the database.
-        :rtype: (int, [CouchDocument])
+        :rtype: (int, [ServerDocument])
         """
         return self._database.get_all_docs(include_deleted)
 
     def _put_doc(self, old_doc, doc):
         """
-        Put the document in the Couch backend database.
+        Put the document in the backend database.
 
         Note that C{old_doc} must have been fetched with the parameter
         C{check_for_conflicts} equal to True, so we can properly update the
         new document using the conflict information from the old one.
 
         :param old_doc: The old document version.
-        :type old_doc: CouchDocument
+        :type old_doc: ServerDocument
         :param doc: The document to be put.
-        :type doc: CouchDocument
+        :type doc: ServerDocument
         """
         last_transaction =\
             self._database.save_document(old_doc, doc,
@@ -348,7 +348,7 @@ class SoledadBackend(CommonBackend):
         This will also set doc.content to None.
 
         :param doc: The document to mark as deleted.
-        :type doc: CouchDocument.
+        :type doc: ServerDocument.
 
         :raise DocumentDoesNotExist: Raised if the document does not
                                             exist.
@@ -372,20 +372,17 @@ class SoledadBackend(CommonBackend):
         self._put_doc(old_doc, doc)
         return new_rev
 
-    def get_doc_conflicts(self, doc_id, couch_rev=None):
+    def get_doc_conflicts(self, doc_id):
         """
         Get the conflicted versions of a document.
 
-        If the C{couch_rev} parameter is not None, conflicts for a specific
-        document's couch revision are returned.
-
-        :param couch_rev: The couch document revision.
-        :type couch_rev: str
+        :param doc_id: The document id.
+        :type doc_id: str
 
         :return: A list of conflicted versions of the document.
         :rtype: list
         """
-        return self._database.get_doc_conflicts(doc_id, couch_rev)
+        return self._database.get_doc_conflicts(doc_id)
 
     def _get_replica_gen_and_trans_id(self, other_replica_uid):
         """
@@ -478,7 +475,7 @@ class SoledadBackend(CommonBackend):
         Add a conflict and force a document put.
 
         :param doc: The document to be put.
-        :type doc: CouchDocument
+        :type doc: ServerDocument
         """
         my_doc = self._get_doc(doc.doc_id)
         self._prune_conflicts(doc, vectorclock.VectorClockRev(doc.rev))
@@ -499,7 +496,7 @@ class SoledadBackend(CommonBackend):
         the time you GET_DOC_CONFLICTS until the point where you RESOLVE)
 
         :param doc: A Document with the new content to be inserted.
-        :type doc: CouchDocument
+        :type doc: ServerDocument
         :param conflicted_doc_revs: A list of revisions that the new content
                                     supersedes.
         :type conflicted_doc_revs: [str]
@@ -564,7 +561,7 @@ class SoledadBackend(CommonBackend):
         remote copy is never updated again.)
 
         :param doc: A document object
-        :type doc: CouchDocument
+        :type doc: ServerDocument
         :param save_conflict: If this document is a conflict, do you want to
                               save it as a conflict, or just ignore it.
         :type save_conflict: bool
@@ -596,7 +593,7 @@ class SoledadBackend(CommonBackend):
                  'converged', at_gen is the insertion/current generation.
         :rtype: (str, int)
         """
-        if not isinstance(doc, CouchDocument):
+        if not isinstance(doc, ServerDocument):
             doc = self._factory(doc.doc_id, doc.rev, doc.get_json())
         my_doc = self._get_doc(doc.doc_id, check_for_conflicts=True)
         if my_doc:
@@ -636,7 +633,7 @@ class SoledadBackend(CommonBackend):
         Originally in u1db.CommonBackend
 
         :param doc: The document to have conflicts pruned.
-        :type doc: CouchDocument
+        :type doc: ServerDocument
         :param doc_vcr: A vector clock representing the current document's
                         revision.
         :type doc_vcr: u1db.vectorclock.VectorClock
diff --git a/common/src/leap/soledad/common/couch/__init__.py b/common/src/leap/soledad/common/couch/__init__.py
index 727f033f..1780cecd 100644
--- a/common/src/leap/soledad/common/couch/__init__.py
+++ b/common/src/leap/soledad/common/couch/__init__.py
@@ -1,5 +1,5 @@
 # -*- coding: utf-8 -*-
-# couch.py
+# __init__.py
 # Copyright (C) 2013 LEAP
 #
 # This program is free software: you can redistribute it and/or modify
@@ -54,7 +54,7 @@ from leap.soledad.common import ddocs
 from leap.soledad.common.errors import raise_server_error
 from leap.soledad.common.errors import raise_missing_design_doc_error
 from leap.soledad.common.errors import InvalidURLError
-from leap.soledad.common.document import CouchDocument
+from leap.soledad.common.document import ServerDocument
 from leap.soledad.common.backend import SoledadBackend
 
 
@@ -78,8 +78,8 @@ def list_users_dbs(couch_url):
     return users
 
 
-# monkey-patch the u1db http app to use CouchDocument
-http_app.Document = CouchDocument
+# monkey-patch the u1db http app to use ServerDocument
+http_app.Document = ServerDocument
 
 
 @contextmanager
@@ -254,10 +254,10 @@ class CouchDatabase(object):
                                 documents will not be included in the results.
         :type include_deleted: bool
 
-        :return: (generation, [CouchDocument])
+        :return: (generation, [ServerDocument])
             The current generation of the database, followed by a list of all
             the documents in the database.
-        :rtype: (int, [CouchDocument])
+        :rtype: (int, [ServerDocument])
         """
 
         generation, _ = self._get_generation_info()
@@ -316,7 +316,7 @@ class CouchDatabase(object):
         :type check_for_conflicts: bool
 
         :return: The document.
-        :rtype: CouchDocument
+        :rtype: ServerDocument
         """
         # get document with all attachments (u1db content and eventual
         # conflicts)
@@ -333,7 +333,7 @@ class CouchDatabase(object):
         # restrict to u1db documents
         if 'u1db_rev' not in result:
             return None
-        doc = CouchDocument(doc_id, result['u1db_rev'])
+        doc = ServerDocument(doc_id, result['u1db_rev'])
         # set contents or make tombstone
         if '_attachments' not in result \
                 or 'u1db_content' not in result['_attachments']:
@@ -368,7 +368,7 @@ class CouchDatabase(object):
         """
         conflicts = []
         for doc_rev, content in attached_conflicts:
-            doc = CouchDocument(doc_id, doc_rev)
+            doc = ServerDocument(doc_id, doc_rev)
             if content is None:
                 doc.make_tombstone()
             else:
@@ -652,9 +652,9 @@ class CouchDatabase(object):
         new document using the conflict information from the old one.
 
         :param old_doc: The old document version.
-        :type old_doc: CouchDocument
+        :type old_doc: ServerDocument
         :param doc: The document to be put.
-        :type doc: CouchDocument
+        :type doc: ServerDocument
 
         :raise RevisionConflict: Raised when trying to update a document but
                                  couch revisions mismatch.
@@ -712,7 +712,7 @@ class CouchDatabase(object):
             '_attachments': attachments,
         }
         # if we are updating a doc we have to add the couch doc revision
-        if old_doc is not None:
+        if old_doc is not None and hasattr(old_doc, 'couch_rev'):
             couch_doc['_rev'] = old_doc.couch_rev
         # prepare the multipart PUT
         buf = StringIO()
diff --git a/common/src/leap/soledad/common/document.py b/common/src/leap/soledad/common/document.py
index 05458906..20510544 100644
--- a/common/src/leap/soledad/common/document.py
+++ b/common/src/leap/soledad/common/document.py
@@ -110,18 +110,17 @@ class SoledadDocument(Document):
         doc="Wrapper to ensure `doc.rev` is always returned as bytes.")
 
 
-class CouchDocument(SoledadDocument):
+class ServerDocument(SoledadDocument):
     """
-    This is the document used for maintaining the Couch backend.
+    This is the document used by server to hold conflicts and transactions
+    on a database.
 
-    A CouchDocument can fetch and manipulate conflicts and also holds a
-    reference to the couch document revision. This data is used to ensure an
-    atomic and consistent update of the database.
+    The goal is to ensure an atomic and consistent update of the database.
     """
 
     def __init__(self, doc_id=None, rev=None, json='{}', has_conflicts=False):
         """
-        Container for handling a document that is stored in couch backend.
+        Container for handling a document that stored on server.
 
         :param doc_id: The unique document identifier.
         :type doc_id: str
@@ -133,7 +132,6 @@ class CouchDocument(SoledadDocument):
         :type has_conflicts: bool
         """
         SoledadDocument.__init__(self, doc_id, rev, json, has_conflicts)
-        self.couch_rev = None
         self.transactions = None
         self._conflicts = None
 
@@ -142,7 +140,7 @@ class CouchDocument(SoledadDocument):
         Get the conflicted versions of the document.
 
         :return: The conflicted versions of the document.
-        :rtype: [CouchDocument]
+        :rtype: [ServerDocument]
         """
         return self._conflicts or []
 
@@ -161,7 +159,7 @@ class CouchDocument(SoledadDocument):
         Add a conflict to this document.
 
         :param doc: The conflicted version to be added.
-        :type doc: CouchDocument
+        :type doc: Document
         """
         if self._conflicts is None:
             raise Exception("Fetch conflicts first!")
@@ -181,12 +179,3 @@ class CouchDocument(SoledadDocument):
             lambda doc: doc.rev not in conflict_revs,
             self._conflicts)
         self.has_conflicts = len(self._conflicts) > 0
-
-    def update(self, new_doc):
-        # update info
-        self.rev = new_doc.rev
-        if new_doc.is_tombstone():
-            self.is_tombstone()
-        else:
-            self.content = new_doc.content
-        self.has_conflicts = new_doc.has_conflicts
diff --git a/common/src/leap/soledad/common/tests/test_couch.py b/common/src/leap/soledad/common/tests/test_couch.py
index 1634d30c..01f0587b 100644
--- a/common/src/leap/soledad/common/tests/test_couch.py
+++ b/common/src/leap/soledad/common/tests/test_couch.py
@@ -36,7 +36,7 @@ from u1db import SyncTarget
 from u1db import vectorclock
 
 from leap.soledad.common import couch
-from leap.soledad.common import backend
+from leap.soledad.common.document import ServerDocument
 from leap.soledad.common import errors
 
 from leap.soledad.common.tests import u1db_tests as tests
@@ -47,8 +47,6 @@ from leap.soledad.common.tests.util import sync_via_synchronizer
 from leap.soledad.common.tests.u1db_tests import test_backends
 from leap.soledad.common.tests.u1db_tests import DatabaseBaseTests
 
-from u1db.backends.inmemory import InMemoryIndex
-
 
 # -----------------------------------------------------------------------------
 # The following tests come from `u1db.tests.test_common_backend`.
@@ -134,7 +132,7 @@ def copy_couch_database_for_test(test, db):
 
 
 def make_document_for_test(test, doc_id, rev, content, has_conflicts=False):
-    return couch.CouchDocument(
+    return ServerDocument(
         doc_id, rev, content, has_conflicts=has_conflicts)