From 8d81c1c91336cb554f8fa98fcf664dd7c6b27c69 Mon Sep 17 00:00:00 2001
From: Daniel M <daniel.maruani@gmail.com>
Date: Sat, 1 Jul 2023 15:17:45 -0400
Subject: [PATCH] feat:implement json.merge

Fix #181
---
 .github/workflows/test.yml     |  2 +-
 fakeredis/stack/_json_mixin.py | 32 ++++++++++++++++++++++++++++----
 test/test_json/test_json.py    | 28 ++++++++++++++++------------
 3 files changed, 45 insertions(+), 17 deletions(-)

diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
index 6dff2b70..97b6676d 100644
--- a/.github/workflows/test.yml
+++ b/.github/workflows/test.yml
@@ -61,7 +61,7 @@ jobs:
             lupa: true
             hypothesis: true
           - python-version: "3.11"
-            redis-image: "redis/redis-stack-server:7.0.6-RC3"
+            redis-image: "redis/redis-stack-server:7.2.0-RC2"
             redis-py: "4.6.0"
             lupa: true
             json: true
diff --git a/fakeredis/stack/_json_mixin.py b/fakeredis/stack/_json_mixin.py
index 573649d4..6edab756 100644
--- a/fakeredis/stack/_json_mixin.py
+++ b/fakeredis/stack/_json_mixin.py
@@ -7,7 +7,7 @@
 # Standard Library Imports
 import json
 from json import JSONDecodeError
-from typing import Any, Union
+from typing import Any, Union, Dict
 
 from jsonpath_ng import Root, JSONPath
 from jsonpath_ng.exceptions import JsonPathParserError
@@ -46,6 +46,21 @@ def _path_is_root(path: JSONPath) -> bool:
     return path == Root()
 
 
+def _dict_deep_merge(source: Dict, destination: Dict) -> Dict:
+    """Deep merge of two dictionaries
+    """
+    for key, value in source.items():
+        if value is None and key in destination:
+            del destination[key]
+        elif isinstance(value, dict):
+            node = destination.setdefault(key, {})
+            _dict_deep_merge(value, node)
+        else:
+            destination[key] = value
+
+    return destination
+
+
 class JSONObject:
     """Argument converter for JSON objects."""
 
@@ -440,6 +455,15 @@ def json_mset(self, *args):
             JSONCommandsMixin._json_set(key, path_str, value)
         return helpers.OK
 
-    # @command(name="JSON.MERGE", fixed=(Key(), bytes, bytes), repeat=(bytes,), flags=msgs.FLAG_LEAVE_EMPTY_VAL)
-    # def json_merge(self, key, path_str, mult_by, *args):
-    #     pass  # TODO
+    @command(name="JSON.MERGE", fixed=(Key(), bytes, JSONObject), repeat=(), flags=msgs.FLAG_LEAVE_EMPTY_VAL)
+    def json_merge(self, key, path_str: bytes, value: JsonType):
+        path: JSONPath = _parse_jsonpath(path_str)
+        if key.value is not None and (type(key.value) is not dict) and not _path_is_root(path):
+            raise SimpleError(msgs.JSON_WRONG_REDIS_TYPE)
+        matching = path.find(key.value)
+        for item in matching:
+            prev_value = item.value if item is not None else dict()
+            _dict_deep_merge(value, prev_value)
+        if len(matching) > 0:
+            key.updated()
+        return helpers.OK
diff --git a/test/test_json/test_json.py b/test/test_json/test_json.py
index 3e2a6f97..4284bf3a 100644
--- a/test/test_json/test_json.py
+++ b/test/test_json/test_json.py
@@ -558,27 +558,31 @@ def test_nummultby(r: redis.Redis):
         assert r.json().nummultby("doc1", ".b[0].a", 3) == 6
 
 
-@testtools.run_test_if_redispy_ver('above', '5')
+@testtools.run_test_if_redispy_ver('above', '4.6')
+@pytest.mark.min_server('7.1')
 def test_json_merge(r: redis.Redis):
     # Test with root path $
-    key = "person_data"
-    r.json().set(key, Path.root_path(), {"person1": {"personal_data": {"name": "John"}}}, )
-    r.json().merge(key, Path.root_path(), {"person1": {"personal_data": {"hobbies": "reading"}}})
-    assert r.json().get(key) == {"person1": {"personal_data": {"name": "John", "hobbies": "reading"}}}
+    assert r.json().set("person_data", "$", {"person1": {"personal_data": {"name": "John"}}}, )
+    assert r.json().merge("person_data", "$", {"person1": {"personal_data": {"hobbies": "reading"}}})
+    assert r.json().get("person_data") == {"person1": {"personal_data": {"name": "John", "hobbies": "reading"}}}
 
     # Test with root path path $.person1.personal_data
-    r.json().merge(key, "$.person1.personal_data", {"country": "Israel"})
-    assert r.json().get(key) == {
-        "person1": {"personal_data": {"name": "John", "hobbies": "reading", "country": "Israel"}}}
+    assert r.json().merge("person_data", "$.person1.personal_data", {"country": "Israel"})
+    assert r.json().get("person_data") == {"person1": {
+        "personal_data": {"name": "John", "hobbies": "reading", "country": "Israel"}
+    }}
 
     # Test with null value to delete a value
-    r.json().merge("person_data", "$.person1.personal_data", {"name": None})
-    assert r.json().get(key) == {"person1": {"personal_data": {"country": "Israel", "hobbies": "reading"}}}
+    assert r.json().merge("person_data", "$.person1.personal_data", {"name": None})
+    assert r.json().get("person_data") == {
+        "person1": {"personal_data": {"country": "Israel", "hobbies": "reading"}}
+    }
 
 
-@testtools.run_test_if_redispy_ver('above', '5')
+@testtools.run_test_if_redispy_ver('above', '4.6')
+@pytest.mark.min_server('7.1')
 def test_mset(r: redis.Redis):
-    r.json().mset("1", Path.root_path(), 1, "2", Path.root_path(), 2)
+    r.json().mset([("1", Path.root_path(), 1), ("2", Path.root_path(), 2)])
 
     assert r.json().mget(["1"], Path.root_path()) == [1]
     assert r.json().mget(["1", "2"], Path.root_path()) == [1, 2]