add mypy type hints to all non-test code + update mypy config (#300)

* begin adding type hints

* fixes

* more hints

* 1

* 1

* 1

* type hint marshmallow converters

* 1

* revert

* change import to hopefully make compatible with older python

* more fixes for old python

* fix for old marshmallow

* generator v2

* v3 generator

* swagger objects

* more typing

* add a few missing hints

* add typed

* minor fixes

* update type + rerun black

* more type hints

* finish adding type hints

* fix tests

* address comments

* fix

* minor fix

* fix typo

.pre-commit-config.yaml

@@ -10,7 +10,7 @@ repos:
     hooks:
       - id: flake8
   - repo: https://github.com/pre-commit/mirrors-mypy
-    rev: v1.4.1
+    rev: v1.8.0
     hooks:
       - id: mypy
   - repo: https://github.com/Lucas-C/pre-commit-hooks-markup

flask_rebar/__init__.py

@@ -12,10 +12,10 @@
 
 from flask_rebar.validation import ResponseSchema, RequestSchema
 
-from flask_rebar.swagger_generation import (
+from flask_rebar.swagger_generation.swagger_generator_v2 import SwaggerV2Generator
+from flask_rebar.swagger_generation.swagger_generator_v3 import SwaggerV3Generator
+from flask_rebar.swagger_generation.swagger_objects import (
     ExternalDocumentation,
-    SwaggerV2Generator,
-    SwaggerV3Generator,
     Tag,
     Server,
     ServerVariable,

flask_rebar/authenticators/base.py

@@ -15,7 +15,7 @@ class Authenticator:
     extend this class.
     """
 
-    def authenticate(self):
+    def authenticate(self) -> None:
         """
         Implementations of :class:`Authenticator` should override this method.
 

flask_rebar/authenticators/header_api_key.py

@@ -7,14 +7,16 @@
     :copyright: Copyright 2018 PlanGrid, Inc., see AUTHORS.
     :license: MIT, see LICENSE for details.
 """
+from typing import Dict
+
 from flask import request, g
 from hmac import compare_digest
 
 from flask_rebar import errors, messages
 from flask_rebar.authenticators.base import Authenticator
 
 
-def get_authenticated_app_name():
+def get_authenticated_app_name() -> str:
     return g.authenticated_app_name
 
 
@@ -39,16 +41,16 @@ class HeaderApiKeyAuthenticator(Authenticator):
     # This is the default name, if someone doesn't need about this feature.
     DEFAULT_APP_NAME = "default"
 
-    def __init__(self, header, name="sharedSecret"):
+    def __init__(self, header: str, name: str = "sharedSecret") -> None:
         self.header = header
-        self.keys = {}
+        self.keys: Dict[str, str] = {}
         self.name = name
 
     @property
-    def authenticated_app_name(self):
+    def authenticated_app_name(self) -> str:
         return get_authenticated_app_name()
 
-    def register_key(self, key, app_name=DEFAULT_APP_NAME):
+    def register_key(self, key: str, app_name: str = DEFAULT_APP_NAME) -> None:
         """
         Register a client application's shared secret.
 
@@ -60,7 +62,7 @@ def register_key(self, key, app_name=DEFAULT_APP_NAME):
         """
         self.keys[key] = app_name
 
-    def authenticate(self):
+    def authenticate(self) -> None:
         if self.header not in request.headers:
             raise errors.Unauthorized(messages.missing_auth_token)
 

flask_rebar/compat.py

@@ -1,25 +1,32 @@
+from typing import Any
+from typing import Dict
+
 import marshmallow
+from marshmallow.fields import Field
+from marshmallow.schema import Schema
 
 from flask import current_app
 from flask_rebar.validation import filter_dump_only, RequireOnDumpMixin
 
 
-def set_data_key(field, key):
+def set_data_key(field: Field, key: str) -> Field:
     field.data_key = key
     return field
 
 
-def get_data_key(field):
+def get_data_key(field: Field) -> str:
     if field.data_key:
         return field.data_key
+    if field.name is None:
+        raise ValueError("Field name cannot be None")
     return field.name
 
 
-def load(schema, data):
+def load(schema: Schema, data: Dict[str, Any]) -> Dict[str, Any]:
     return schema.load(data)
 
 
-def dump(schema, data):
+def dump(schema: Schema, data: Dict[str, Any]) -> Dict[str, Any]:
     """
     Our wrapper for Schema.dump that includes optional validation.
     Note that as of Flask-Rebar 2.x (hence Marshmallow 3.x), Marshmallow's default behavior is to NOT validate on dump
@@ -54,6 +61,6 @@ def dump(schema, data):
     return result
 
 
-def exclude_unknown_fields(schema):
+def exclude_unknown_fields(schema: Schema) -> Schema:
     schema.unknown = marshmallow.EXCLUDE
     return schema

flask_rebar/errors.py

@@ -7,6 +7,8 @@
     :copyright: Copyright 2018 PlanGrid, Inc., see AUTHORS.
     :license: MIT, see LICENSE for details.
 """
+from flask_rebar.messages import ErrorMessage
+from typing import Any, Dict, Optional, Union
 
 
 class HttpJsonError(Exception):
@@ -30,7 +32,11 @@ class HttpJsonError(Exception):
     default_message: str
     http_status_code: int
 
-    def __init__(self, msg=None, additional_data=None):
+    def __init__(
+        self,
+        msg: Optional[Union[str, ErrorMessage]] = None,
+        additional_data: Optional[Dict[str, Any]] = None,
+    ) -> None:
         self.error_message = msg or self.default_message
         self.additional_data = additional_data
         super().__init__(self.error_message)

flask_rebar/messages.py

@@ -65,21 +65,21 @@ class ErrorCode:
 )
 
 
-def required_field_missing(field_name):
+def required_field_missing(field_name: str) -> ErrorMessage:
     return ErrorMessage(
         f"Required field missing: {field_name}",
         ErrorCode.REQUIRED_FIELD_MISSING,
     )
 
 
-def required_field_empty(field_name):
+def required_field_empty(field_name: str) -> ErrorMessage:
     return ErrorMessage(
         f"Value for required field cannot be None: {field_name}",
         ErrorCode.REQUIRED_FIELD_EMPTY,
     )
 
 
-def unsupported_fields(field_names):
+def unsupported_fields(field_names: str) -> ErrorMessage:
     return ErrorMessage(
         "Unexpected field: {}".format(",".join(field_names)),
         ErrorCode.UNSUPPORTED_FIELDS,