Remove support for marshmallow2

Anywhere that version dispatch was used, switch to the ma3 version of
the code. Tests skipped on marshmallow3 are dropped.

Remove dict2schema, since it is now redundant with Schema.from_dict .

Update the changelog and docstrings around `unknown=...` to remove
note that it only works on marshmallow3. Remove any documentation
which notes a marshmallow2 (vs ma3) discrepancy or a way of getting
the same behavior out of both versions.

Update readme badge to ma3 only.

tox and azure pipelines config are altered to drop marshmallow2
builds.

Update `setup.py` to require `marshmallow>=3.0.0`

closes #540

Author: sirosen

CHANGELOG.rst

@@ -4,6 +4,27 @@ Changelog
 7.0.0 (Unreleased)
 ******************
 
+Refactoring:
+
+* *Backwards-incompatible*: Remove support for marshmallow2 (:issue:`539`)
+
+* *Backwards-incompatible*: Remove `dict2schema`
+
+  Users desiring the `dict2schema` functionality may now rely upon
+  `marshmallow.Schema.from_dict`. Rewrite any code using `dict2schema` like so:
+
+.. code-block:: python
+
+    import marshmallow as ma
+
+    # webargs 6.x and older
+    from webargs import dict2schema
+
+    myschema = dict2schema({"q1", ma.fields.Int()})
+
+    # webargs 7.x
+    myschema = ma.Schema.from_dict({"q1", ma.fields.Int()})
+
 Features:
 
 * Add a new ``unknown`` parameter to ``Parser.parse``, ``Parser.use_args``, and
@@ -17,7 +38,7 @@ This allows usages like
 
     import marshmallow as ma
 
-    # marshmallow 3 only, for use of ``unknown`` and ``EXCLUDE``
+
     @parser.use_kwargs(
         {"q1": ma.fields.Int(), "q2": ma.fields.Int()}, location="query", unknown=ma.EXCLUDE
     )

README.rst

@@ -14,9 +14,9 @@ webargs
    :target: https://webargs.readthedocs.io/
    :alt: Documentation
 
-.. image:: https://badgen.net/badge/marshmallow/2,3?list=1
+.. image:: https://badgen.net/badge/marshmallow/3
     :target: https://marshmallow.readthedocs.io/en/latest/upgrading.html
-    :alt: marshmallow 2/3 compatible
+    :alt: marshmallow 3 compatible
 
 .. image:: https://badgen.net/badge/code%20style/black/000
     :target: https://github.com/ambv/black

azure-pipelines.yml

@@ -27,15 +27,13 @@ jobs:
     toxenvs:
       - lint
 
-      - py35-marshmallow2
-      - py35-marshmallow3
+      - py35
 
-      - py36-marshmallow3
+      - py36
 
-      - py37-marshmallow3
+      - py37
 
-      - py38-marshmallow2
-      - py38-marshmallow3
+      - py38
 
       - py38-marshmallowdev
 

docs/advanced.rst

@@ -107,10 +107,6 @@ When you need more flexibility in defining input schemas, you can pass a marshma
         last_name = fields.Str(missing="")
         date_registered = fields.DateTime(dump_only=True)
 
-        # NOTE: Uncomment below two lines if you're using marshmallow 2
-        # class Meta:
-        #    strict = True
-
 
     @use_args(UserSchema())
     def profile_view(args):
@@ -131,9 +127,6 @@ When you need more flexibility in defining input schemas, you can pass a marshma
         username = args["username"]
         # ...
 
-.. warning::
-    If you're using marshmallow 2, you should always set ``strict=True`` (either as a ``class Meta`` option or in the Schema's constructor) when passing a schema to webargs. This will ensure that the parser's error handler is invoked when expected.
-
 
 When to avoid `use_kwargs`
 --------------------------

docs/quickstart.rst

@@ -25,9 +25,7 @@ Arguments are specified as a dictionary of name -> :class:`Field <marshmallow.fi
         "languages": fields.DelimitedList(fields.Str()),
         # When value is keyed on a variable-unsafe name
         # or you want to rename a key
-        "user_type": fields.Str(load_from="user-type"),
-        # OR, on marshmallow 3
-        # "user_type": fields.Str(data_key="user-type"),
+        "user_type": fields.Str(data_key="user-type"),
     }
 
 .. note::

setup.py

@@ -70,7 +70,7 @@ def read(fname):
     url="https://github.com/marshmallow-code/webargs",
     packages=find_packages("src"),
     package_dir={"": "src"},
-    install_requires=["marshmallow>=2.15.2"],
+    install_requires=["marshmallow>=3.0.0"],
     extras_require=EXTRAS_REQUIRE,
     license="MIT",
     zip_safe=False,

src/webargs/__init__.py

@@ -5,9 +5,8 @@
 from marshmallow import validate
 
 from webargs.core import ValidationError
-from webargs.dict2schema import dict2schema
 from webargs import fields
 
 __version__ = "7.0.0-dev"
 __version_info__ = tuple(LooseVersion(__version__).version)
-__all__ = ("dict2schema", "ValidationError", "fields", "missing", "validate")
+__all__ = ("ValidationError", "fields", "missing", "validate")

src/webargs/asyncparser.py

@@ -9,7 +9,6 @@
 from marshmallow.fields import Field
 import marshmallow as ma
 
-from webargs.compat import MARSHMALLOW_VERSION_INFO
 from webargs import core
 
 Request = typing.TypeVar("Request")
@@ -41,9 +40,7 @@ async def parse(
         req = req if req is not None else self.get_default_request()
         location = location or self.location
         unknown = unknown or self.unknown
-        load_kwargs = (
-            {"unknown": unknown} if MARSHMALLOW_VERSION_INFO[0] >= 3 and unknown else {}
-        )
+        load_kwargs = {"unknown": unknown}
         if req is None:
             raise ValueError("Must pass req object")
         data = None
@@ -53,8 +50,7 @@ async def parse(
             location_data = await self._load_location_data(
                 schema=schema, req=req, location=location
             )
-            result = schema.load(location_data, **load_kwargs)
-            data = result.data if core.MARSHMALLOW_VERSION_INFO[0] < 3 else result
+            data = schema.load(location_data, **load_kwargs)
             self._validate_arguments(data, validators)
         except ma.exceptions.ValidationError as error:
             await self._on_validation_error(
@@ -132,7 +128,7 @@ def use_args(
         # Optimization: If argmap is passed as a dictionary, we only need
         # to generate a Schema once
         if isinstance(argmap, Mapping):
-            argmap = core.dict2schema(argmap, schema_class=self.schema_class)()
+            argmap = self.schema_class.from_dict(argmap)()
 
         def decorator(func: typing.Callable) -> typing.Callable:
             req_ = request_obj

src/webargs/compat.py

@@ -2,24 +2,20 @@
 import inspect
 import typing
 import logging
-import warnings
 from collections.abc import Mapping
 import json
 
 import marshmallow as ma
 from marshmallow import ValidationError
 from marshmallow.utils import missing
 
-from webargs.compat import MARSHMALLOW_VERSION_INFO
-from webargs.dict2schema import dict2schema
 from webargs.fields import DelimitedList
 
 logger = logging.getLogger(__name__)
 
 
 __all__ = [
     "ValidationError",
-    "dict2schema",
     "is_multiple",
     "Parser",
     "missing",
@@ -214,13 +210,7 @@ def _get_schema(self, argmap, req):
         elif callable(argmap):
             schema = argmap(req)
         else:
-            schema = dict2schema(argmap, schema_class=self.schema_class)()
-        if MARSHMALLOW_VERSION_INFO[0] < 3 and not schema.strict:
-            warnings.warn(
-                "It is highly recommended that you set strict=True on your schema "
-                "so that the parser's error handler will be invoked when expected.",
-                UserWarning,
-            )
+            schema = self.schema_class.from_dict(argmap)()
         return schema
 
     def parse(
@@ -245,7 +235,7 @@ def parse(
             default, that means one of ``('json', 'query', 'querystring',
             'form', 'headers', 'cookies', 'files', 'json_or_form')``.
         :param str unknown: A value to pass for ``unknown`` when calling the
-            schema's ``load`` method (marshmallow 3 only).
+            schema's ``load`` method.
         :param callable validate: Validation function or list of validation functions
             that receives the dictionary of parsed arguments. Validator either returns a
             boolean or raises a :exc:`ValidationError`.
@@ -259,9 +249,7 @@ def parse(
         req = req if req is not None else self.get_default_request()
         location = location or self.location
         unknown = unknown or self.unknown
-        load_kwargs = (
-            {"unknown": unknown} if MARSHMALLOW_VERSION_INFO[0] >= 3 and unknown else {}
-        )
+        load_kwargs = {"unknown": unknown}
         if req is None:
             raise ValueError("Must pass req object")
         data = None
@@ -271,8 +259,7 @@ def parse(
             location_data = self._load_location_data(
                 schema=schema, req=req, location=location
             )
-            result = schema.load(location_data, **load_kwargs)
-            data = result.data if MARSHMALLOW_VERSION_INFO[0] < 3 else result
+            data = schema.load(location_data, **load_kwargs)
             self._validate_arguments(data, validators)
         except ma.exceptions.ValidationError as error:
             self._on_validation_error(
@@ -344,7 +331,7 @@ def greet(args):
             which accepts a request and returns a `marshmallow.Schema`.
         :param str location: Where on the request to load values.
         :param str unknown: A value to pass for ``unknown`` when calling the
-            schema's ``load`` method (marshmallow 3 only).
+            schema's ``load`` method.
         :param bool as_kwargs: Whether to insert arguments as keyword arguments.
         :param callable validate: Validation function that receives the dictionary
             of parsed arguments. If the function returns ``False``, the parser
@@ -359,7 +346,7 @@ def greet(args):
         # Optimization: If argmap is passed as a dictionary, we only need
         # to generate a Schema once
         if isinstance(argmap, Mapping):
-            argmap = dict2schema(argmap, schema_class=self.schema_class)()
+            argmap = self.schema_class.from_dict(argmap)()
 
         def decorator(func):
             req_ = request_obj