Add country types

docs/reference/types.md

@@ -2,10 +2,18 @@
 
 Outlines provides custom Pydantic types so you can focus on your use case rather than on writing regular expressions:
 
-- Using `outlines.types.ZipCode` will generate valid US Zip(+4) codes.
-- Using `outlines.types.PhoneNumber` will generate valid US phone numbers.
-- Using `outlines.types.ISBN` will generate ISBNs. Note that there is no guarantee that the [check digit](https://en.wikipedia.org/wiki/ISBN#Check_digits) will be correct.
-- Using `outlines.types.airports.IATA` will generate valid airport IATA codes.
+
+| Category | Type | Import | Description |
+|:--------:|:----:|:-------|:------------|
+| Zip code | US | `outlines.types.ZipCode` | Generate US Zip(+4) codes |
+| Phone number  | US | `outlines.types.PhoneNumber` | Generate valid US phone numbers |
+| ISBN | 10 & 13 | `outlines.types.ISBN` | There is no guarantee that the [check digit][wiki-isbn] will be correct |
+| Airport | IATA | `outlines.types.airports.IATA` | Valid [airport IATA codes][wiki-airport-iata] |
+| Country | alpha-2 code | `outlines.types.airports.Alpha2` | Valid [country alpha-2 codes][wiki-country-alpha-2] |
+|  | alpha-3 code | `outlines.types.countries.Alpha3` | Valid [country alpha-3 codes][wiki-country-alpha-3] |
+|  | numeric code | `outlines.types.countries.Numeric` | Valid [country numeric codes][wiki-country-numeric] |
+|  | name | `outlines.types.countries.Name` | Valid country names |
+|  | flag | `outlines.types.countries.Flag` | Valid flag emojis |
 
 You can use these types in Pydantic schemas for JSON-structured generation:
 
@@ -49,3 +57,10 @@ print(result)
 
 
 We plan on adding many more custom types. If you have found yourself writing regular expressions to generate fields of a given type, or if you could benefit from more specific types don't hesite to [submit a PR](https://github.com/outlines-dev/outlines/pulls) or [open an issue](https://github.com/outlines-dev/outlines/issues/new/choose).
+
+
+[wiki-isbn]: https://en.wikipedia.org/wiki/ISBN#Check_digits
+[wiki-airport-iata]: https://en.wikipedia.org/wiki/IATA_airport_code
+[wiki-country-alpha-2]: https://en.wikipedia.org/wiki/ISO_3166-1_alpha-2
+[wiki-country-alpha-3]: https://en.wikipedia.org/wiki/ISO_3166-1_alpha-3
+[wiki-country-numeric]: https://en.wikipedia.org/wiki/ISO_3166-1_numeric

outlines/fsm/types.py

@@ -32,10 +32,12 @@ def custom_format_fn(sequence: str) -> Any:
 
     if isinstance(python_type, EnumMeta):
         values = python_type.__members__.keys()
-        regex_str = "(" + "|".join(values) + ")"
-        format_fn = lambda x: str(x)
+        enum_regex_str: str = "(" + "|".join(values) + ")"
 
-        return regex_str, format_fn
+        def enum_format_fn(sequence: str) -> str:
+            return str(sequence)
+
+        return enum_regex_str, enum_format_fn
 
     if python_type == float:
 

outlines/types/__init__.py

@@ -1,4 +1,4 @@
+from . import airports, countries
 from .isbn import ISBN
 from .phone_numbers import PhoneNumber
 from .zip_codes import ZipCode
-from . import airports

outlines/types/countries.py

@@ -0,0 +1,24 @@
+"""Generate valid country codes and names."""
+from enum import Enum
+
+try:
+    import pycountry
+except ImportError:
+    raise ImportError(
+        'The `countries` module requires "pycountry" to be installed. You can install it with "pip install pycountry"'
+    )
+
+ALPHA_2_CODE = [(country.alpha_2, country.alpha_2) for country in pycountry.countries]
+Alpha2 = Enum("Alpha_2", ALPHA_2_CODE)  # type:ignore
+
+ALPHA_3_CODE = [(country.alpha_3, country.alpha_3) for country in pycountry.countries]
+Alpha3 = Enum("Alpha_2", ALPHA_3_CODE)  # type:ignore
+
+NUMERIC_CODE = [(country.numeric, country.numeric) for country in pycountry.countries]
+Numeric = Enum("Numeric_code", NUMERIC_CODE)  # type:ignore
+
+NAME = [(country.name, country.name) for country in pycountry.countries]
+Name = Enum("Name", NAME)  # type:ignore
+
+FLAG = [(country.flag, country.flag) for country in pycountry.countries]
+Flag = Enum("Flag", FLAG)  # type:ignore

pyproject.toml

@@ -57,6 +57,8 @@ test = [
     "vllm",
     "torch",
     "transformers",
+    "pycountry",
+    "pyairports",
 ]
 serve = [
     "vllm>=0.3.0",
@@ -126,6 +128,7 @@ module = [
     "vllm.*",
     "uvicorn.*",
     "fastapi.*",
+    "pycountry.*",
     "pyairports.*",
 ]
 ignore_missing_imports = true

tests/test_types.py

@@ -47,10 +47,19 @@ class Model(BaseModel):
     [
         (types.airports.IATA, "CDG", True),
         (types.airports.IATA, "XXX", False),
+        (types.countries.Alpha2, "FR", True),
+        (types.countries.Alpha2, "XX", False),
+        (types.countries.Alpha3, "UKR", True),
+        (types.countries.Alpha3, "XXX", False),
+        (types.countries.Numeric, "004", True),
+        (types.countries.Numeric, "900", False),
+        (types.countries.Name, "Ukraine", True),
+        (types.countries.Name, "Wonderland", False),
+        (types.countries.Flag, "🇿🇼", True),
+        (types.countries.Flag, "🤗", False),
     ],
 )
 def test_type_enum(custom_type, test_string, should_match):
-
     type_name = custom_type.__name__
 
     class Model(BaseModel):