Implement transaction undo (#380)

Author: DavidMStraub

gramps_webapi/api/resources/transactions.py

@@ -1,7 +1,7 @@
 #
 # Gramps Web API - A RESTful API for the Gramps genealogy program
 #
-# Copyright (C) 2021      David Straub
+# Copyright (C) 2021-2023      David Straub
 #
 # 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
@@ -29,6 +29,7 @@
 from gramps.gen.errors import HandleError
 from gramps.gen.lib.serialize import from_json, to_json
 from gramps.gen.merge.diff import diff_items
+from webargs import fields
 
 from ...auth.const import PERM_ADD_OBJ, PERM_DEL_OBJ, PERM_EDIT_OBJ
 from ..auth import require_permissions
@@ -38,27 +39,41 @@
     get_db_handle,
     get_search_indexer,
     get_tree_from_jwt,
+    use_args,
 )
 from . import ProtectedResource
-from .util import transaction_to_json
+from .util import reverse_transaction, transaction_to_json
 
 trans_code = {"delete": TXNDEL, "add": TXNADD, "update": TXNUPD}
 
 
 class TransactionsResource(ProtectedResource):
     """Resource for raw database transactions."""
 
-    def post(self) -> Response:
+    @use_args(
+        {
+            "undo": fields.Boolean(load_default=False),
+        },
+        location="query",
+    )
+    def post(self, args) -> Response:
         """Post the transaction."""
         require_permissions([PERM_ADD_OBJ, PERM_EDIT_OBJ, PERM_DEL_OBJ])
         payload = request.json
         if not payload:
             abort(400)  # disallow empty payload
+        is_undo = args["undo"]
+        if is_undo:
+            payload = reverse_transaction(payload)
         db_handle = get_db_handle(readonly=False)
-        new_people = sum(
+        num_people_deleted = sum(
+            item["type"] == "delete" and item["_class"] == "Person" for item in payload
+        )
+        num_people_added = sum(
             item["type"] == "add" and item["_class"] == "Person" for item in payload
         )
-        check_quota_people(to_add=new_people)
+        num_people_new = num_people_added - num_people_deleted
+        check_quota_people(to_add=num_people_new)
         with DbTxn("Raw transaction", db_handle) as trans:
             for item in payload:
                 try:

gramps_webapi/api/resources/util.py

@@ -70,7 +70,7 @@
 from gramps.gen.utils.place import conv_lat_lon
 
 from ...const import DISABLED_IMPORTERS, SEX_FEMALE, SEX_MALE, SEX_UNKNOWN
-from ...types import FilenameOrPath, Handle
+from ...types import FilenameOrPath, Handle, TransactionJson
 from ..media import get_media_handler
 from ..util import get_db_handle, get_tree_from_jwt
 
@@ -1059,7 +1059,7 @@ def _fix_parent_handles(
             db_handle.commit_person(person, trans)
 
 
-def transaction_to_json(transaction: DbTxn) -> List[Dict[str, Any]]:
+def transaction_to_json(transaction: DbTxn) -> TransactionJson:
     """Return a JSON representation of a database transaction."""
     out = []
     for recno in transaction.get_recnos(reverse=False):
@@ -1085,6 +1085,22 @@ def transaction_to_json(transaction: DbTxn) -> List[Dict[str, Any]]:
     return out
 
 
+def reverse_transaction(transaction_list: TransactionJson) -> TransactionJson:
+    """Reverse a JSON representation of a database transaction."""
+    transaction_reversed = []
+    type_reversed = {"add": "delete", "delete": "add", "update": "update"}
+    for item in reversed(transaction_list):
+        item_reversed = {
+            "type": type_reversed[item["type"]],
+            "handle": item["handle"],
+            "_class": item["_class"],
+            "old": item["new"],
+            "new": item["old"],
+        }
+        transaction_reversed.append(item_reversed)
+    return transaction_reversed
+
+
 def hash_object(obj: GrampsObject) -> str:
     """Generate a SHA256 hash for a Gramps object's data."""
     data = to_json(obj).encode()

gramps_webapi/data/apispec.yaml

@@ -4485,6 +4485,11 @@ paths:
       consumes:
         - application/json
       parameters:
+        - name: undo
+          in: query
+          required: false
+          type: boolean
+          description: "If true, apply the inverse of the transaction."
         - in: body
           name: source
           description: The database transaction

gramps_webapi/types.py

@@ -1,7 +1,7 @@
 #
 # Gramps Web API - A RESTful API for the Gramps genealogy program
 #
-# Copyright (C) 2020      David Straub
+# Copyright (C) 2020-2023      David Straub
 #
 # 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
@@ -20,8 +20,9 @@
 """Custom types."""
 
 from pathlib import Path
-from typing import NewType, Union
+from typing import Any, Dict, List, NewType, Union
 
 Handle = NewType("Handle", str)
 GrampsId = NewType("GrampsId", str)
 FilenameOrPath = Union[str, Path]
+TransactionJson = List[Dict[str, Any]]

tests/test_endpoints/test_transactions.py

@@ -1,7 +1,7 @@
 #
 # Gramps Web API - A RESTful API for the Gramps genealogy program
 #
-# Copyright (C) 2020      David Straub
+# Copyright (C) 2020-2023      David Straub
 #
 # 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
@@ -109,6 +109,25 @@ def test_transaction_add_update_delete(self):
         obj_dict = rv.json
         self.assertEqual(obj_dict["handle"], handle)
         self.assertEqual(obj_dict["text"]["string"], "My first note.")
+        # undo add
+        rv = self.client.post(
+            "/api/transactions/?undo=1", json=trans_dict, headers=headers
+        )
+        assert rv.status_code == 200
+        trans_dict = rv.json
+        self.assertEqual(len(trans_dict), 1)
+        self.assertEqual(trans_dict[0]["handle"], handle)
+        self.assertEqual(trans_dict[0]["type"], "delete")
+        self.assertEqual(trans_dict[0]["_class"], "Note")
+        rv = self.client.get(f"/api/notes/{handle}", headers=headers)
+        self.assertEqual(rv.status_code, 404)
+        # undo undo
+        rv = self.client.post(
+            "/api/transactions/?undo=1", json=trans_dict, headers=headers
+        )
+        assert rv.status_code == 200
+        rv = self.client.get(f"/api/notes/{handle}", headers=headers)
+        self.assertEqual(rv.status_code, 200)
         # update
         obj_new = deepcopy(obj)
         obj_new["gramps_id"] = "N2"
@@ -123,11 +142,27 @@ def test_transaction_add_update_delete(self):
         ]
         rv = self.client.post("/api/transactions/", json=trans, headers=headers)
         self.assertEqual(rv.status_code, 200)
+        trans_dict = rv.json
         rv = self.client.get(f"/api/notes/{handle}", headers=headers)
         self.assertEqual(rv.status_code, 200)
         obj_dict = rv.json
         self.assertEqual(obj_dict["handle"], handle)
         self.assertEqual(obj_dict["gramps_id"], "N2")
+        # undo update
+        rv = self.client.post(
+            "/api/transactions/?undo=1", json=trans_dict, headers=headers
+        )
+        assert rv.status_code == 200
+        trans_dict = rv.json
+        rv = self.client.get(f"/api/notes/{handle}", headers=headers)
+        self.assertEqual(rv.status_code, 200)
+        obj_dict = rv.json
+        self.assertEqual(obj_dict["handle"], handle)
+        self.assertEqual(obj_dict["gramps_id"], "N1")
+        # undo undo
+        rv = self.client.post(
+            "/api/transactions/?undo=1", json=trans_dict, headers=headers
+        )
         # delete
         trans = [
             {
@@ -140,8 +175,70 @@ def test_transaction_add_update_delete(self):
         ]
         rv = self.client.post("/api/transactions/", json=trans, headers=headers)
         self.assertEqual(rv.status_code, 200)
+        trans_dict = rv.json
         rv = self.client.get(f"/api/notes/{handle}", headers=headers)
         self.assertEqual(rv.status_code, 404)
+        # undo delete
+        rv = self.client.post(
+            "/api/transactions/?undo=1", json=trans_dict, headers=headers
+        )
+        self.assertEqual(rv.status_code, 200)
+        trans_dict = rv.json
+        rv = self.client.get(f"/api/notes/{handle}", headers=headers)
+        self.assertEqual(rv.status_code, 200)
+        # undo undo
+        rv = self.client.post(
+            "/api/transactions/?undo=1", json=trans_dict, headers=headers
+        )
+
+    def test_family_undo(self):
+        """Undo update and subequent deletion of a single note."""
+        father = {
+            "_class": "Person",
+            "handle": make_handle(),
+            "gramps_id": "P1",
+        }
+        mother = {
+            "_class": "Person",
+            "handle": make_handle(),
+            "gramps_id": "P2",
+        }
+        family = {
+            "_class": "Family",
+            "handle": make_handle(),
+            "gramps_id": "F1",
+            "father_handle": father["handle"],
+            "mother_handle": mother["handle"],
+        }
+        headers = get_headers(self.client, "editor", "123")
+        # add objects
+        rv = self.client.post("/api/people/", json=father, headers=headers)
+        assert rv.status_code == 201
+        rv = self.client.post("/api/people/", json=mother, headers=headers)
+        assert rv.status_code == 201
+        rv = self.client.post("/api/families/", json=family, headers=headers)
+        assert rv.status_code == 201
+        trans_dict = rv.json
+        rv = self.client.get(f"/api/people/{father['handle']}", headers=headers)
+        assert rv.status_code == 200
+        assert rv.json["family_list"] == [family["handle"]]
+        rv = self.client.get(f"/api/people/{mother['handle']}", headers=headers)
+        assert rv.status_code == 200
+        assert rv.json["family_list"] == [family["handle"]]
+        rv = self.client.get(f"/api/families/{family['handle']}", headers=headers)
+        assert rv.status_code == 200
+        # undo family post should delete the family and update the people
+        rv = self.client.post(
+            "/api/transactions/?undo=1", json=trans_dict, headers=headers
+        )
+        rv = self.client.get(f"/api/people/{father['handle']}", headers=headers)
+        assert rv.status_code == 200
+        assert rv.json["family_list"] == []
+        rv = self.client.get(f"/api/people/{mother['handle']}", headers=headers)
+        assert rv.status_code == 200
+        assert rv.json["family_list"] == []
+        rv = self.client.get(f"/api/families/{family['handle']}", headers=headers)
+        assert rv.status_code == 404
 
     def test_modify_two(self):
         """Modify two objects simultaneously."""