Support date,time,date-time,uuid formats

Author: aschwa

outlines/fsm/json_schema.py

@@ -24,6 +24,18 @@
     "null": NULL,
 }
 
+DATE_TIME = r"(-?(?:[1-9][0-9]*)?[0-9]{4})-(1[0-2]|0[1-9])-(3[01]|0[1-9]|[12][0-9])T(2[0-3]|[01][0-9]):([0-5][0-9]):([0-5][0-9])(\.[0-9]{3})?(Z)?"
+DATE = r"(?:\d{4})-(?:0[1-9]|1[0-2])-(?:0[1-9]|[1-2][0-9]|3[0-1])"
+TIME = r"(2[0-3]|[01][0-9]):([0-5][0-9]):([0-5][0-9])(\\.[0-9]+)?(Z)?"
+UUID = r"[0-9a-f]{8}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{12}"
+
+format_to_regex = {
+    "uuid": UUID,
+    "date-time": DATE_TIME,
+    "date": DATE,
+    "time": TIME,
+}
+
 
 def build_regex_from_object(object: Union[str, Callable, BaseModel]):
     """Turn a JSON schema into a regex that matches any JSON object that follows
@@ -210,6 +222,20 @@ def to_regex(resolver: Resolver, instance: dict):
                     return rf'(^"{pattern[1:-1]}"$)'
                 else:
                     return rf'("{pattern}")'
+            elif "format" in instance:
+                format = instance["format"]
+                if format == "date-time":
+                    return format_to_regex["date-time"]
+                elif format == "uuid":
+                    return format_to_regex["uuid"]
+                elif format == "date":
+                    return format_to_regex["date"]
+                elif format == "time":
+                    return format_to_regex["time"]
+                else:
+                    raise NotImplementedError(
+                        f"Format {format} is not supported by Outlines"
+                    )
             else:
                 return type_to_regex["string"]
 

tests/fsm/test_json_schema.py

@@ -7,11 +7,15 @@
 
 from outlines.fsm.json_schema import (
     BOOLEAN,
+    DATE,
+    DATE_TIME,
     INTEGER,
     NULL,
     NUMBER,
     STRING,
     STRING_INNER,
+    TIME,
+    UUID,
     build_regex_from_object,
     get_schema_from_signature,
     to_regex,
@@ -451,3 +455,75 @@ def test_match(schema, regex, examples):
             assert match.span() == (0, len(string))
         else:
             assert match is None
+
+
+@pytest.mark.parametrize(
+    "schema,regex,examples",
+    [
+        # UUID
+        (
+            {"title": "Foo", "type": "string", "format": "uuid"},
+            UUID,
+            [
+                ("123e4567-e89b-12d3-a456-426614174000", True),
+                ("123e4567-e89b-12d3-a456-42661417400", False),
+                ("123e4567-e89b-12d3-a456-42661417400g", False),
+                ("123e4567-e89b-12d3-a456-42661417400-", False),
+                ("", False),
+            ],
+        ),
+        # DATE-TIME
+        (
+            {"title": "Foo", "type": "string", "format": "date-time"},
+            DATE_TIME,
+            [
+                ("2018-11-13T20:20:39Z", True),
+                ("2016-09-18T17:34:02.666Z", True),
+                ("2008-05-11T15:30:00Z", True),
+                ("2021-01-01T00:00:00", True),
+                ("2022-01-10 07:19:30", False),  # missing T
+                ("2022-12-10T10-04-29", False),  # incorrect separator
+                ("2023-01-01", False),
+            ],
+        ),
+        # DATE
+        (
+            {"title": "Foo", "type": "string", "format": "date"},
+            DATE,
+            [
+                ("2018-11-13", True),
+                ("2016-09-18", True),
+                ("2008-05-11", True),
+                ("2015-13-01", False),  # incorrect month
+                ("2022-01", False),  # missing day
+                ("2022/12/01", False),  # incorrect separator"
+            ],
+        ),
+        # TIME
+        (
+            {"title": "Foo", "type": "string", "format": "time"},
+            TIME,
+            [
+                ("20:20:39Z", True),
+                ("15:30:00Z", True),
+                ("25:30:00", False),  # incorrect hour
+                ("15:30", False),  # missing seconds
+                ("15:30:00.000", False),  # missing Z
+                ("15-30-00", False),  # incorrect separator
+                ("15:30:00+01:00", False),  # incorrect separator
+            ],
+        ),
+    ],
+)
+def test_format(schema, regex, examples):
+    schema = json.dumps(schema)
+    test_regex = build_regex_from_object(schema)
+    assert test_regex == regex
+
+    for string, does_match in examples:
+        match = re.fullmatch(test_regex, string)
+        if does_match:
+            assert match[0] == string
+            assert match.span() == (0, len(string))
+        else:
+            assert match is None