add serialization and deserialization

.gitignore

@@ -134,6 +134,7 @@ dmypy.json
 *.sqlite3
 /src/static
 /src/deployments.info
+/src/playground.py
 /src/media/
 server_setup/
 

src/rule_engine/rule.py

@@ -1,3 +1,4 @@
+import json
 import re
 import typing as t
 from enum import Enum
@@ -24,7 +25,7 @@ class Operator(str, Enum):
     NE = "ne"
     EQ = "eq"
     REGEX = "regex"
-    FUNC = "func"
+    # FUNC = "func"
 
 
 AND, OR = "AND", "OR"
@@ -59,7 +60,7 @@ def _regex(field_value: t.Any, pattern: t.Any) -> bool:
     raise ValueError("The value for the `REGEX` operator must be a string or a compiled regex pattern.")
 
 
-def _func(field_value: t.Any, func: t.Callable[[t.Any], bool]) -> bool:
+def _func(field_value: t.Any, func: t.Callable[[t.Any], bool]) -> bool:  # pragma: no cover
     if callable(func):
         return func(field_value)
     raise ValueError("The value for the `FUNC` operator must be a callable.")
@@ -84,7 +85,7 @@ def _func(field_value: t.Any, func: t.Callable[[t.Any], bool]) -> bool:
     Operator.NE: lambda fv, cv: fv != cv,
     Operator.EQ: lambda fv, cv: fv == cv,
     Operator.REGEX: _regex,
-    Operator.FUNC: _func,
+    # Operator.FUNC: _func,
 }
 
 
@@ -151,13 +152,12 @@ def _eval() -> bool:
                 return condition.evaluate(example)
             else:
                 for key, value in condition.items():
-                    print(key, value)
                     if "__" in key:
                         field, op = key.split("__", 1)
                         if not self._evaluate_operator(op, example.get(field, None), value):
                             return False
                     else:
-                        if key not in example or example[key] != value:
+                        if not self._evaluate_operator("eq", example.get(key, None), value):
                             return False
                 return True
 
@@ -189,6 +189,42 @@ def evaluate(self, example: t.Dict[str, t.Any]) -> bool:
 
         return result if result is not None else False
 
+    def to_dict(self) -> dict[str, t.Any]:
+        return {
+            "$rule": True,
+            "id": self.id,
+            "negated": self.negated,
+            "conditions": [
+                {"operator": op, "condition": cond.to_dict() if isinstance(cond, Rule) else cond}
+                for op, cond in self.conditions
+            ],
+        }
+
+    @classmethod
+    def from_dict(cls, data: dict[str, t.Any]) -> "Rule":
+        rule = cls()
+        if not data.get("$rule"):
+            raise ValueError("Invalid rule data")
+        rule._id = data["id"]
+        rule._negated = data["negated"]
+        for cond in data["conditions"]:
+            operator = cond["operator"]
+            condition = cond["condition"]
+            if isinstance(condition, dict) and condition.get("$rule"):
+                condition = cls.from_dict(condition)
+            rule.conditions.append((operator, condition))
+        return rule
+
+    def to_json(self, *args: t.Any, **kwargs: t.Any) -> str:
+        """Serialize the Rule to a JSON string."""
+        return json.dumps(self.to_dict(), *args, **kwargs)
+
+    @classmethod
+    def from_json(cls, json_str: str) -> "Rule":
+        """Deserialize a Rule from a JSON string."""
+        data = json.loads(json_str)
+        return cls.from_dict(data)
+
     def __repr__(self) -> str:
         return f"{self.__class__.__name__}(conditions={self.conditions}, negated={self.negated})"
 

src/rule_engine/tests/test_rule_engine.py

@@ -42,8 +42,8 @@
         (Operator.EQ, 3, 4, False),
         (Operator.REGEX, "hello123", r"\w+\d+", True),
         (Operator.REGEX, "hello", r"\d+", False),
-        (Operator.FUNC, "hello", lambda x: x.startswith("he"), True),
-        (Operator.FUNC, "hello", lambda x: x.endswith("lo"), True),
+        # (Operator.FUNC, "hello", lambda x: x.startswith("he"), True),
+        # (Operator.FUNC, "hello", lambda x: x.endswith("lo"), True),
     ],
 )
 def test_operator_evaluation(operator: str, field_value: t.Any, condition_value: t.Any, expected: bool) -> None:
@@ -56,7 +56,7 @@ def test_operator_evaluation(operator: str, field_value: t.Any, condition_value:
         (Operator.STARTSWITH, 5, "hello"),
         (Operator.ENDSWITH, "hello", 5),
         (Operator.REGEX, 5, "hello"),
-        (Operator.FUNC, 5, "hello"),
+        # (Operator.FUNC, 5, "hello"),
     ),
 )
 def test_operator_evaluation_value_error(operator: str, field_value: t.Any, condition_value: t.Any) -> None:
@@ -168,3 +168,24 @@ def test_and_value_error() -> None:
 def test_or_value_error() -> None:
     with pytest.raises(ValueError):
         Rule() | "invalid_rule"  # type: ignore[operator]
+
+
+def test_to_json_and_from_json() -> None:
+    rule = Rule(Rule(foo="bar") | Rule(foo="baz"), name="John", age__gte=21)
+    rule_json = rule.to_json()
+    loaded_rule = Rule.from_json(rule_json)
+    assert rule.to_dict() == loaded_rule.to_dict()
+    example_true = {"foo": "bar", "name": "John", "age": 22}
+    example_false = {"foo": "qux", "name": "Jane", "age": 19}
+    assert evaluate(rule, example_true)
+    assert not evaluate(rule, example_false)
+    assert evaluate(loaded_rule, example_true)
+    assert not evaluate(loaded_rule, example_false)
+
+
+def test_to_load_rule_invalid() -> None:
+    rule = Rule(Rule(foo="bar"))
+    rule_json = rule.to_dict()
+    rule_json.pop("$rule")
+    with pytest.raises(ValueError):
+        Rule.from_dict(rule_json)