Split the Flask-Login login manager initialization from the init_app method to the __init_login_manager method in the DigestAuth class, to simplify the code.

.readthedocs.yaml

@@ -0,0 +1,40 @@
+# The Flask HTTP Digest Authentication Project.
+# Author: imacat@mail.imacat.idv.tw (imacat), 2023/4/5
+
+#  Copyright (c) 2023 imacat.
+#
+#  Licensed under the Apache License, Version 2.0 (the "License");
+#  you may not use this file except in compliance with the License.
+#  You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+#  Unless required by applicable law or agreed to in writing, software
+#  distributed under the License is distributed on an "AS IS" BASIS,
+#  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+#  See the License for the specific language governing permissions and
+#  limitations under the License.
+
+# .readthedocs.yaml
+# Read the Docs configuration file
+# See https://docs.readthedocs.io/en/stable/config-file/v2.html for details
+
+# Required
+version: 2
+
+# Set the version of Python and other tools you might need
+build:
+  os: ubuntu-22.04
+  tools:
+    python: "3.8"
+
+# Build documentation in the docs/ directory with Sphinx
+
+# If using Sphinx, optionally build your docs in additional formats such as PDF
+formats: all
+
+# Optionally declare the Python requirements required to build your docs
+python:
+   install:
+   - method: pip
+     path: .

MANIFEST.in

@@ -15,4 +15,7 @@
 #  See the License for the specific language governing permissions and
 #  limitations under the License.
 
-include tests/*
+recursive-include docs *
+recursive-exclude docs/build *
+recursive-include tests *
+recursive-exclude tests *.pyc

README.rst

@@ -6,7 +6,7 @@ Flask HTTP Digest Authentication
 Description
 ===========
 
-*Flask-Digest-Auth* is an `HTTP Digest Authentication`_ implementation
+*Flask-DigestAuth* is an `HTTP Digest Authentication`_ implementation
 for Flask_ applications.  It authenticates the user for the protected
 views.
 
@@ -16,11 +16,11 @@ HTTP Digest Authentication is specified in `RFC 2617`_.
 Why HTTP Digest Authentication?
 -------------------------------
 
-HTTP Digest Authentication has the advantage that it does not send the
-actual password to the server, which greatly enhances the security.
-It uses the challenge-response authentication scheme.  The client
-returns the response calculated from the challenge and the password,
-but not the original password.
+*HTTP Digest Authentication* has the advantage that it does not send
+thee actual password to the server, which greatly enhances the
+security.  It uses the challenge-response authentication scheme.  The
+client returns the response calculated from the challenge and the
+password, but not the original password.
 
 Log in forms has the advantage of freedom, in the senses of both the
 visual design and the actual implementation.  You may implement your
@@ -28,405 +28,44 @@ own challenge-response log in form, but then you are reinventing the
 wheels.  If a pretty log in form is not critical to your project, HTTP
 Digest Authentication should be a good choice.
 
-Flask-Digest-Auth works with Flask-Login_.  Log in protection can be
+Flask-DigestAuth works with Flask-Login_.  Log in protection can be
 separated with the authentication mechanism.  You can create protected
 Flask modules without knowing the actual authentication mechanisms.
 
 
-Features
---------
-
-There are a couple of Flask HTTP digest authentication
-implementations.  Flask-Digest-Auth has the following features:
-
-
-Flask-Login Integration
-#######################
-
-Flask-Digest-Auth features Flask-Login integration.  The views
-can be totally independent with the actual authentication mechanism.
-You can write a Flask module that requires log in, without specify
-the actual authentication mechanism.  The application can specify
-either HTTP Digest Authentication, or the log in forms, as needed.
-
-
-Session Integration
-###################
-
-Flask-Digest-Auth features session integration.  The user log in
-is remembered in the session.  The authentication information is not
-requested again.  This is different to the practice of the HTTP Digest
-Authentication, but is convenient for the log in accounting.
-
-
-Log Out Support
-###############
-
-Flask-Digest-Auth supports log out.  The user will be prompted for
-new username and password.
-
-
-Log In Bookkeeping
-##################
-
-You can register a callback to run when the user logs in.
-
-
-.. _HTTP Digest Authentication: https://en.wikipedia.org/wiki/Digest_access_authentication
-.. _RFC 2617: https://www.rfc-editor.org/rfc/rfc2617
-.. _Flask: https://flask.palletsprojects.com
-.. _Flask-Login: https://flask-login.readthedocs.io
-
-
 Installation
 ============
 
-You can install Flask-Digest-Auth with ``pip``:
+You can install Flask-DigestAuth with ``pip``:
 
 ::
 
-    pip install Flask-Digest-Auth
+    pip install Flask-DigestAuth
 
 You may also install the latest source from the
-`Flask-Digest-Auth GitHub repository`_.
+`Flask-DigestAuth GitHub repository`_.
 
 ::
 
-    git clone git@github.com:imacat/flask-digest-auth.git
-    cd flask-digest-auth
-    pip install .
+    pip install git+https://github.com/imacat/flask-digestauth.git
 
-.. _Flask-Digest-Auth GitHub repository: https://github.com/imacat/flask-digest-auth
 
-
-Flask-Digest-Auth Alone
-=======================
-
-Flask-Digest-Auth can authenticate the users alone.
-
-The currently logged-in user can be retrieved at ``g.user``, if any.
-
-
-Example for Simple Applications with Flask-Digest-Auth Alone
-------------------------------------------------------------
-
-In your ``my_app.py``:
-
-::
-
-    from flask import Flask, request, redirect
-    from flask_digest_auth import DigestAuth
-
-    app: flask = Flask(__name__)
-    ... (Configure the Flask application) ...
-
-    auth: DigestAuth = DigestAuth(realm="Admin")
-    auth.init_app(app)
-
-    @auth.register_get_password
-    def get_password_hash(username: str) -> t.Optional[str]:
-        ... (Load the password hash) ...
-
-    @auth.register_get_user
-    def get_user(username: str) -> t.Optional[t.Any]:
-        ... (Load the user) ...
-
-    @app.get("/admin")
-    @auth.login_required
-    def admin():
-        return f"Hello, {g.user.username}!"
-
-    @app.post("/logout")
-    @auth.login_required
-    def logout():
-        auth.logout()
-        return redirect(request.form.get("next"))
-
-
-Example for Larger Applications with ``create_app()`` with Flask-Digest-Auth Alone
-----------------------------------------------------------------------------------
-
-In your ``my_app/__init__.py``:
-
-::
-
-    from flask import Flask
-    from flask_digest_auth import DigestAuth
-
-    auth: DigestAuth = DigestAuth()
-
-    def create_app(test_config = None) -> Flask:
-        app: flask = Flask(__name__)
-        ... (Configure the Flask application) ...
-
-        auth.realm = app.config["REALM"]
-        auth.init_app(app)
-
-        @auth.register_get_password
-        def get_password_hash(username: str) -> t.Optional[str]:
-            ... (Load the password hash) ...
-
-        @auth.register_get_user
-        def get_user(username: str) -> t.Optional[t.Any]:
-            ... (Load the user) ...
-
-        return app
-
-In your ``my_app/views.py``:
-
-::
-
-    from my_app import auth
-    from flask import Flask, Blueprint, request, redirect
-
-    bp = Blueprint("admin", __name__, url_prefix="/admin")
-
-    @bp.get("/admin")
-    @auth.login_required
-    def admin():
-        return f"Hello, {g.user.username}!"
-
-    @app.post("/logout")
-    @auth.login_required
-    def logout():
-        auth.logout()
-        return redirect(request.form.get("next"))
-
-    def init_app(app: Flask) -> None:
-        app.register_blueprint(bp)
-
-
-Flask-Login Integration
-=======================
-
-Flask-Digest-Auth can work with Flask-Login.  You can write a Flask
-module that requires log in, without specifying the authentication
-mechanism.  The Flask application can specify the actual
-authentication mechanism as it sees fit.
-
-``login_manager.init_app(app)`` must be called before
-``auth.init_app(app)``.
-
-The currently logged-in user can be retrieved at
-``flask_login.current_user``, if any.
-
-
-Example for Simple Applications with Flask-Login Integration
-------------------------------------------------------------
-
-In your ``my_app.py``:
-
-::
-
-    import flask_login
-    from flask import Flask, request, redirect
-    from flask_digest_auth import DigestAuth
-
-    app: flask = Flask(__name__)
-    ... (Configure the Flask application) ...
-
-    login_manager: flask_login.LoginManager = flask_login.LoginManager()
-    login_manager.init_app(app)
-
-    @login_manager.user_loader
-    def load_user(user_id: str) -> t.Optional[User]:
-        ... (Load the user with the username) ...
-
-    auth: DigestAuth = DigestAuth(realm="Admin")
-    auth.init_app(app)
-
-    @auth.register_get_password
-    def get_password_hash(username: str) -> t.Optional[str]:
-        ... (Load the password hash) ...
-
-    @app.get("/admin")
-    @flask_login.login_required
-    def admin():
-        return f"Hello, {flask_login.current_user.get_id()}!"
-
-    @app.post("/logout")
-    @flask_login.login_required
-    def logout():
-        auth.logout()
-        # Do not call flask_login.logout_user()
-        return redirect(request.form.get("next"))
-
-
-Example for Larger Applications with ``create_app()`` with Flask-Login Integration
-----------------------------------------------------------------------------------
-
-In your ``my_app/__init__.py``:
-
-::
-
-    from flask import Flask
-    from flask_digest_auth import DigestAuth
-    from flask_login import LoginManager
-
-    auth: DigestAuth = DigestAuth()
-
-    def create_app(test_config = None) -> Flask:
-        app: flask = Flask(__name__)
-        ... (Configure the Flask application) ...
-
-        login_manager: LoginManager = LoginManager()
-        login_manager.init_app(app)
-
-        @login_manager.user_loader
-        def load_user(user_id: str) -> t.Optional[User]:
-            ... (Load the user with the username) ...
-
-        auth.realm = app.config["REALM"]
-        auth.init_app(app)
-
-        @auth.register_get_password
-        def get_password_hash(username: str) -> t.Optional[str]:
-            ... (Load the password hash) ...
-
-        return app
-
-In your ``my_app/views.py``:
-
-::
-
-    import flask_login
-    from flask import Flask, Blueprint, request, redirect
-    from my_app import auth
-
-    bp = Blueprint("admin", __name__, url_prefix="/admin")
-
-    @bp.get("/admin")
-    @flask_login.login_required
-    def admin():
-        return f"Hello, {flask_login.current_user.get_id()}!"
-
-    @app.post("/logout")
-    @flask_login.login_required
-    def logout():
-        auth.logout()
-        # Do not call flask_login.logout_user()
-        return redirect(request.form.get("next"))
-
-    def init_app(app: Flask) -> None:
-        app.register_blueprint(bp)
-
-The views only depend on Flask-Login, but not the actual
-authentication mechanism.  You can change the actual authentication
-mechanism without changing the views.
-
-
-Setting the Password Hash
-=========================
-
-The password hash of the HTTP Digest Authentication is composed of the
-realm, the username, and the password.  Example for setting the
-password:
-
-::
-
-    from flask_digest_auth import make_password_hash
-
-    user.password = make_password_hash(realm, username, password)
-
-The username is part of the hash.  If the user changes their username,
-you need to ask their password, to generate and store the new password
-hash.
-
-
-Log Out
-=======
-
-Call ``auth.logout()`` when the user wants to log out.
-Besides the usual log out routine, ``auth.logout()`` actually causes
-the next browser automatic authentication to fail, forcing the browser
-to ask the user for the username and password again.
-
-
-Log In Bookkeeping
-==================
-
-You can register a callback to run when the user logs in, for ex.,
-logging the log in event, adding the log in counter, etc.
-
-::
-
-    @auth.register_on_login
-    def on_login(user: User) -> None:
-        user.visits = user.visits + 1
-
-
-Writing Tests
+Documentation
 =============
 
-You can write tests with our test client that handles HTTP Digest
-Authentication.
-
-Example for a unittest_ test case:
-
-::
-
-    from flask import Flask
-    from flask_digest_auth import Client
-    from flask_testing import TestCase
-    from my_app import create_app
-
-    class MyTestCase(TestCase):
-
-        def create_app(self):
-            app: Flask = create_app({
-                "SECRET_KEY": token_urlsafe(32),
-                "TESTING": True
-            })
-            app.test_client_class = Client
-            return app
-
-        def test_admin(self):
-            response = self.client.get("/admin")
-            self.assertEqual(response.status_code, 401)
-            response = self.client.get(
-                "/admin", digest_auth=("my_name", "my_pass"))
-            self.assertEqual(response.status_code, 200)
+Refer to the `documentation on Read the Docs`_.
 
 
+Change Log
+==========
 
-Example for a pytest_ test:
-
-::
-
-    import pytest
-    from flask import Flask
-    from flask_digest_auth import Client
-    from my_app import create_app
-
-    @pytest.fixture()
-    def app():
-        app: Flask = create_app({
-            "SECRET_KEY": token_urlsafe(32),
-            "TESTING": True
-        })
-        app.test_client_class = Client
-        yield app
-
-    @pytest.fixture()
-    def client(app):
-        return app.test_client()
-
-    def test_admin(app: Flask, client: Client):
-        with app.app_context():
-            response = self.client.get("/admin")
-            assert response.status_code == 401
-            response = self.client.get(
-                "/admin", digest_auth=("my_name", "my_pass"))
-            assert response.status_code == 200
-
-.. _unittest: https://docs.python.org/3/library/unittest.html
-.. _pytest: https://pytest.org
+Refer to the `change log`_.
 
 
 Copyright
 =========
 
- Copyright (c) 2022 imacat.
+ Copyright (c) 2022-2023 imacat.
 
  Licensed under the Apache License, Version 2.0 (the "License");
  you may not use this file except in compliance with the License.
@@ -447,3 +86,11 @@ Authors
 | imacat
 | imacat@mail.imacat.idv.tw
 | 2022/11/23
+
+.. _HTTP Digest Authentication: https://en.wikipedia.org/wiki/Digest_access_authentication
+.. _RFC 2617: https://www.rfc-editor.org/rfc/rfc2617
+.. _Flask: https://flask.palletsprojects.com
+.. _Flask-DigestAuth GitHub repository: https://github.com/imacat/flask-digestauth
+.. _Flask-Login: https://flask-login.readthedocs.io
+.. _documentation on Read the Docs: https://flask-digestauth.readthedocs.io
+.. _change log: https://flask-digestauth.readthedocs.io/en/latest/changelog.html

docs/Makefile

@@ -0,0 +1,20 @@
+# Minimal makefile for Sphinx documentation
+#
+
+# You can set these variables from the command line, and also
+# from the environment for the first two.
+SPHINXOPTS    ?=
+SPHINXBUILD   ?= sphinx-build
+SOURCEDIR     = source
+BUILDDIR      = build
+
+# Put it first so that "make" without argument is like "make help".
+help:
+	@$(SPHINXBUILD) -M help "$(SOURCEDIR)" "$(BUILDDIR)" $(SPHINXOPTS) $(O)
+
+.PHONY: help Makefile
+
+# Catch-all target: route all unknown targets to Sphinx using the new
+# "make mode" option.  $(O) is meant as a shortcut for $(SPHINXOPTS).
+%: Makefile
+	@$(SPHINXBUILD) -M $@ "$(SOURCEDIR)" "$(BUILDDIR)" $(SPHINXOPTS) $(O)

docs/make.bat

@@ -0,0 +1,35 @@
+@ECHO OFF
+
+pushd %~dp0
+
+REM Command file for Sphinx documentation
+
+if "%SPHINXBUILD%" == "" (
+	set SPHINXBUILD=sphinx-build
+)
+set SOURCEDIR=source
+set BUILDDIR=build
+
+%SPHINXBUILD% >NUL 2>NUL
+if errorlevel 9009 (
+	echo.
+	echo.The 'sphinx-build' command was not found. Make sure you have Sphinx
+	echo.installed, then set the SPHINXBUILD environment variable to point
+	echo.to the full path of the 'sphinx-build' executable. Alternatively you
+	echo.may add the Sphinx directory to PATH.
+	echo.
+	echo.If you don't have Sphinx installed, grab it from
+	echo.https://www.sphinx-doc.org/
+	exit /b 1
+)
+
+if "%1" == "" goto help
+
+%SPHINXBUILD% -M %1 %SOURCEDIR% %BUILDDIR% %SPHINXOPTS% %O%
+goto end
+
+:help
+%SPHINXBUILD% -M help %SOURCEDIR% %BUILDDIR% %SPHINXOPTS% %O%
+
+:end
+popd

docs/source/changelog.rst

@@ -0,0 +1,122 @@
+Change Log
+==========
+
+
+Version 0.6.0
+-------------
+
+Released 2023/4/26
+
+* Updated the minimal Python version to 3.8.
+* Switched from ``setup.cfg`` to ``pyproject.toml``.
+* Added the change log.
+* Simplified ``README.rst``.
+
+
+Version 0.5.0
+-------------
+
+Released 2023/1/6
+
+* Added the ``DIGEST_AUTH_REALM`` configuration variable as the
+  recommended way to set the authentication realm.
+* Changed the default realm from an empty string to
+  ``Login Required``.
+
+
+Version 0.4.0
+-------------
+
+Released 2023/1/4
+
+* Changed the package name from ``flask-digest-auth`` to
+  ``Flask-DigestAuth``, according to the Flask recommended extension
+  guidelines
+  https://flask.palletsprojects.com/en/latest/extensiondev/ .
+* Replaced ``app.digest_auth`` with ``app.extensions["digest-auth"]``
+  to store the ``DigestAuth`` instance.
+* Replaced ``auth.app`` with ``current_app``, to prevent circular
+  imports.
+
+
+Version 0.3.1
+-------------
+
+Released 2022/12/29
+
+Fixed the missing authentication state with disabled users.
+
+
+Version 0.3.0
+-------------
+
+Released 2022/12/7
+
+Changed the visibility of several methods and properties of the
+DigestAuth class that should be private to private.
+
+
+Version 0.2.4
+-------------
+
+Released 2022/12/6
+
+Fixed the pytest example in the documentation.
+
+
+Version 0.2.3
+-------------
+
+Released 2022/12/6
+
+Fixed the dependencies for the documentation hosted on Read the Docs.
+
+
+Version 0.2.2
+-------------
+
+Released 2022/12/6
+
+Added the Sphinx documentation, and hosted the documentation on
+Read the Docs.
+
+
+Version 0.2.1
+-------------
+
+Released 2022/12/6
+
+Various fixes, with the help from SonarQube.
+
+
+Version 0.2.0
+-------------
+
+Released 2022/11/27
+
+* Added log out support.  User can log out.
+* Added on-login event handler.  You can do some accounting when the
+  user logs in.
+
+This release is written in Sydney and on the international flight,
+and released in Taipei.
+
+
+Version 0.1.1
+-------------
+
+Released 2022/11/24
+
+Changed the minimal Python version to 3.7.
+
+Released at Sydney, Australia on vacation.
+
+
+Version 0.1.0
+-------------
+
+Released 2022/11/24
+
+The initial release.
+
+Released at Sydney, Australia on vacation.

docs/source/conf.py

@@ -0,0 +1,33 @@
+# Configuration file for the Sphinx documentation builder.
+#
+# For the full list of built-in configuration values, see the documentation:
+# https://www.sphinx-doc.org/en/master/usage/configuration.html
+import os
+import sys
+
+sys.path.insert(0, os.path.abspath('../../src/'))
+import flask_digest_auth
+
+# -- Project information -----------------------------------------------------
+# https://www.sphinx-doc.org/en/master/usage/configuration.html#project-information
+
+project = 'Flask-DigestAuth'
+copyright = '2022-2023, imacat'
+author = 'imacat'
+release = flask_digest_auth.VERSION
+
+# -- General configuration ---------------------------------------------------
+# https://www.sphinx-doc.org/en/master/usage/configuration.html#general-configuration
+
+extensions = ["sphinx.ext.autodoc"]
+
+templates_path = ['_templates']
+exclude_patterns = []
+
+
+
+# -- Options for HTML output -------------------------------------------------
+# https://www.sphinx-doc.org/en/master/usage/configuration.html#options-for-html-output
+
+html_theme = 'sphinx_rtd_theme'
+html_static_path = ['_static']

docs/source/examples.rst

@@ -0,0 +1,268 @@
+Examples
+========
+
+
+.. _example-alone-simple:
+
+Simple Applications with Flask-DigestAuth Alone
+-----------------------------------------------
+
+In your ``my_app.py``:
+
+::
+
+    from flask import Flask, request, redirect
+    from flask_digest_auth import DigestAuth
+
+    app: flask = Flask(__name__)
+    ... (Configure the Flask application) ...
+
+    auth: DigestAuth = DigestAuth()
+    auth.init_app(app)
+
+    @auth.register_get_password
+    def get_password_hash(username: str) -> t.Optional[str]:
+        ... (Load the password hash) ...
+
+    @auth.register_get_user
+    def get_user(username: str) -> t.Optional[t.Any]:
+        ... (Load the user) ...
+
+    @app.get("/admin")
+    @auth.login_required
+    def admin():
+        return f"Hello, {g.user.username}!"
+
+    @app.post("/logout")
+    @auth.login_required
+    def logout():
+        auth.logout()
+        return redirect(request.form.get("next"))
+
+
+.. _example-alone-large:
+
+Larger Applications with ``create_app()`` with Flask-DigestAuth Alone
+---------------------------------------------------------------------
+
+In your ``my_app/__init__.py``:
+
+::
+
+    from flask import Flask
+    from flask_digest_auth import DigestAuth
+
+    auth: DigestAuth = DigestAuth()
+
+    def create_app(test_config = None) -> Flask:
+        app: flask = Flask(__name__)
+        ... (Configure the Flask application) ...
+
+        auth.init_app(app)
+
+        @auth.register_get_password
+        def get_password_hash(username: str) -> t.Optional[str]:
+            ... (Load the password hash) ...
+
+        @auth.register_get_user
+        def get_user(username: str) -> t.Optional[t.Any]:
+            ... (Load the user) ...
+
+        return app
+
+In your ``my_app/views.py``:
+
+::
+
+    from my_app import auth
+    from flask import Flask, Blueprint, request, redirect
+
+    bp = Blueprint("admin", __name__, url_prefix="/admin")
+
+    @bp.get("/admin")
+    @auth.login_required
+    def admin():
+        return f"Hello, {g.user.username}!"
+
+    @app.post("/logout")
+    @auth.login_required
+    def logout():
+        auth.logout()
+        return redirect(request.form.get("next"))
+
+    def init_app(app: Flask) -> None:
+        app.register_blueprint(bp)
+
+
+.. _example-flask-login-simple:
+
+Simple Applications with Flask-Login Integration
+------------------------------------------------
+
+In your ``my_app.py``:
+
+::
+
+    import flask_login
+    from flask import Flask, request, redirect
+    from flask_digest_auth import DigestAuth
+
+    app: flask = Flask(__name__)
+    ... (Configure the Flask application) ...
+
+    login_manager: flask_login.LoginManager = flask_login.LoginManager()
+    login_manager.init_app(app)
+
+    @login_manager.user_loader
+    def load_user(user_id: str) -> t.Optional[User]:
+        ... (Load the user with the username) ...
+
+    auth: DigestAuth = DigestAuth()
+    auth.init_app(app)
+
+    @auth.register_get_password
+    def get_password_hash(username: str) -> t.Optional[str]:
+        ... (Load the password hash) ...
+
+    @app.get("/admin")
+    @flask_login.login_required
+    def admin():
+        return f"Hello, {flask_login.current_user.get_id()}!"
+
+    @app.post("/logout")
+    @flask_login.login_required
+    def logout():
+        auth.logout()
+        # Do not call flask_login.logout_user()
+        return redirect(request.form.get("next"))
+
+
+.. _example-flask-login-large:
+
+Larger Applications with ``create_app()`` with Flask-Login Integration
+----------------------------------------------------------------------
+
+In your ``my_app/__init__.py``:
+
+::
+
+    from flask import Flask
+    from flask_digest_auth import DigestAuth
+    from flask_login import LoginManager
+
+    auth: DigestAuth = DigestAuth()
+
+    def create_app(test_config = None) -> Flask:
+        app: flask = Flask(__name__)
+        ... (Configure the Flask application) ...
+
+        login_manager: LoginManager = LoginManager()
+        login_manager.init_app(app)
+
+        @login_manager.user_loader
+        def load_user(user_id: str) -> t.Optional[User]:
+            ... (Load the user with the username) ...
+
+        auth.init_app(app)
+
+        @auth.register_get_password
+        def get_password_hash(username: str) -> t.Optional[str]:
+            ... (Load the password hash) ...
+
+        return app
+
+In your ``my_app/views.py``:
+
+::
+
+    import flask_login
+    from flask import Flask, Blueprint, request, redirect
+    from my_app import auth
+
+    bp = Blueprint("admin", __name__, url_prefix="/admin")
+
+    @bp.get("/admin")
+    @flask_login.login_required
+    def admin():
+        return f"Hello, {flask_login.current_user.get_id()}!"
+
+    @app.post("/logout")
+    @flask_login.login_required
+    def logout():
+        auth.logout()
+        # Do not call flask_login.logout_user()
+        return redirect(request.form.get("next"))
+
+    def init_app(app: Flask) -> None:
+        app.register_blueprint(bp)
+
+The views only depend on Flask-Login, but not the actual
+authentication mechanism.  You can change the actual authentication
+mechanism without changing the views.
+
+
+.. _example-unittest:
+
+A unittest Test Case
+--------------------
+
+::
+
+    from flask import Flask
+    from flask_digest_auth import Client
+    from flask_testing import TestCase
+    from my_app import create_app
+
+    class MyTestCase(TestCase):
+
+        def create_app(self):
+            app: Flask = create_app({
+                "TESTING": True,
+                "SECRET_KEY": token_urlsafe(32),
+                "DIGEST_AUTH_REALM": "admin",
+            })
+            app.test_client_class = Client
+            return app
+
+        def test_admin(self):
+            response = self.client.get("/admin")
+            self.assertEqual(response.status_code, 401)
+            response = self.client.get(
+                "/admin", digest_auth=(USERNAME, PASSWORD))
+            self.assertEqual(response.status_code, 200)
+
+
+
+.. _example-pytest:
+
+A pytest Test
+-------------
+
+::
+
+    import pytest
+    from flask import Flask
+    from flask_digest_auth import Client
+    from my_app import create_app
+
+    @pytest.fixture()
+    def app():
+        app: Flask = create_app({
+            "TESTING": True,
+            "SECRET_KEY": token_urlsafe(32),
+            "DIGEST_AUTH_REALM": "admin",
+        })
+        app.test_client_class = Client
+        yield app
+
+    @pytest.fixture()
+    def client(app):
+        return app.test_client()
+
+    def test_admin(app: Flask, client: Client):
+        with app.app_context():
+            response = client.get("/admin")
+            assert response.status_code == 401
+            response = client.get(
+                "/admin", digest_auth=(USERNAME, PASSWORD))
+            assert response.status_code == 200

docs/source/flask_digest_auth.rst

@@ -0,0 +1,37 @@
+flask\_digest\_auth package
+===========================
+
+Submodules
+----------
+
+flask\_digest\_auth.algo module
+-------------------------------
+
+.. automodule:: flask_digest_auth.algo
+   :members:
+   :undoc-members:
+   :show-inheritance:
+
+flask\_digest\_auth.auth module
+-------------------------------
+
+.. automodule:: flask_digest_auth.auth
+   :members:
+   :undoc-members:
+   :show-inheritance:
+
+flask\_digest\_auth.test module
+-------------------------------
+
+.. automodule:: flask_digest_auth.test
+   :members:
+   :undoc-members:
+   :show-inheritance:
+
+Module contents
+---------------
+
+.. automodule:: flask_digest_auth
+   :members:
+   :undoc-members:
+   :show-inheritance:

docs/source/index.rst

@@ -0,0 +1,35 @@
+.. Flask-DigestAuth documentation master file, created by
+   sphinx-quickstart on Wed Dec  7 09:40:48 2022.
+   You can adapt this file completely to your liking, but it should at least
+   contain the root `toctree` directive.
+
+Welcome to Flask-DigestAuth's documentation!
+============================================
+
+*Flask-DigestAuth* is an `HTTP Digest Authentication`_ implementation
+for Flask_ applications.  It authenticates the user for the protected
+views.
+
+HTTP Digest Authentication is specified in `RFC 2617`_.
+
+.. toctree::
+   :maxdepth: 2
+   :caption: Contents:
+
+   intro
+   flask_digest_auth
+   examples
+   changelog
+
+
+
+Indices and tables
+==================
+
+* :ref:`genindex`
+* :ref:`modindex`
+* :ref:`search`
+
+.. _HTTP Digest Authentication: https://en.wikipedia.org/wiki/Digest_access_authentication
+.. _RFC 2617: https://www.rfc-editor.org/rfc/rfc2617
+.. _Flask: https://flask.palletsprojects.com

docs/source/intro.rst

@@ -0,0 +1,155 @@
+Introduction
+============
+
+
+*Flask-DigestAuth* is an `HTTP Digest Authentication`_ implementation
+for Flask_ applications.  It authenticates the user for the protected
+views.
+
+HTTP Digest Authentication is specified in `RFC 2617`_.
+
+
+Why HTTP Digest Authentication?
+-------------------------------
+
+*HTTP Digest Authentication* has the advantage that it does not send
+the actual password to the server, which greatly enhances the
+security.  It uses the challenge-response authentication scheme.  The
+client returns the response calculated from the challenge and the
+password, but not the original password.
+
+Log in forms has the advantage of freedom, in the senses of both the
+visual design and the actual implementation.  You may implement your
+own challenge-response log in form, but then you are reinventing the
+wheels.  If a pretty log in form is not critical to your project, HTTP
+Digest Authentication should be a good choice.
+
+Flask-DigestAuth works with Flask-Login_.  Log in protection can be
+separated with the authentication mechanism.  You can create protected
+Flask modules without knowing the actual authentication mechanisms.
+
+
+Installation
+------------
+
+You can install Flask-DigestAuth with ``pip``:
+
+::
+
+    pip install Flask-DigestAuth
+
+You may also install the latest source from the
+`Flask-DigestAuth GitHub repository`_.
+
+::
+
+    pip install git+https://github.com/imacat/flask-digestauth.git
+
+
+Configuration
+-------------
+
+Flask-DigestAuth takes the configuration ``DIGEST_AUTH_REALM`` as the
+realm.  The default realm is ``Login Required``.
+
+
+Setting the Password
+--------------------
+
+The password hash of the HTTP Digest Authentication is composed of the
+realm, the username, and the password.  Example for setting the
+password:
+
+::
+
+    from flask_digest_auth import make_password_hash
+
+    user.password = make_password_hash(realm, username, password)
+
+The username is part of the hash.  If the user changes their username,
+you need to ask their password, to generate and store the new password
+hash.
+
+See :func:`flask_digest_auth.algo.make_password_hash`.
+
+
+Flask-DigestAuth Alone
+----------------------
+
+Flask-DigestAuth can authenticate the users alone.
+
+See :ref:`example-alone-simple` and :ref:`example-alone-large`.
+
+
+Flask-Login Integration
+-----------------------
+
+Flask-DigestAuth works with Flask-Login_.  You can write a Flask
+module that requires log in, without specifying how to log in.  The
+application can use either HTTP Digest Authentication, or the log in
+forms, as needed.
+
+To use Flask-Login with Flask-DigestAuth,
+``login_manager.init_app(app)`` must be called before
+``auth.init_app(app)``.
+
+The currently logged-in user can be retrieved at
+``flask_login.current_user``, if any.
+
+See :ref:`example-flask-login-simple` and
+:ref:`example-flask-login-large`.
+
+The views only depend on Flask-Login, but not the Flask-DigestAuth.
+You can change the actual authentication mechanism without changing
+the views.
+
+
+Session Integration
+-------------------
+
+Flask-DigestAuth features session integration.  The user log in
+is remembered in the session.  The authentication information is not
+requested again.  This is different to the practice of the HTTP Digest
+Authentication, but is convenient for the log in accounting.
+
+
+Log In Bookkeeping
+------------------
+
+You can register a callback to run when the user logs in, for ex.,
+logging the log in event, adding the log in counter, etc.
+
+::
+
+    @auth.register_on_login
+    def on_login(user: User) -> None:
+        user.visits = user.visits + 1
+
+See :meth:`flask_digest_auth.auth.DigestAuth.register_on_login`.
+
+
+Log Out
+-------
+
+Flask-DigestAuth supports log out.  The user will be prompted for the
+new username and password.
+
+See :meth:`flask_digest_auth.auth.DigestAuth.logout`.
+
+
+Test Client
+-----------
+
+Flask-DigestAuth comes with a test client that supports HTTP digest
+authentication.
+
+See :class:`flask_digest_auth.test.Client`.
+
+Also see :ref:`example-unittest` and :ref:`example-pytest`.
+
+
+.. _HTTP Digest Authentication: https://en.wikipedia.org/wiki/Digest_access_authentication
+.. _RFC 2617: https://www.rfc-editor.org/rfc/rfc2617
+.. _Flask: https://flask.palletsprojects.com
+.. _Flask-Login: https://flask-login.readthedocs.io
+.. _Flask-DigestAuth GitHub repository: https://github.com/imacat/flask-digestauth

docs/source/modules.rst

@@ -0,0 +1,7 @@
+src
+===
+
+.. toctree::
+   :maxdepth: 4
+
+   flask_digest_auth

pyproject.toml

@@ -1,7 +1,7 @@
 # The Flask HTTP Digest Authentication Project.
 # Author: imacat@mail.imacat.idv.tw (imacat), 2022/11/23
 
-#  Copyright (c) 2022 imacat.
+#  Copyright (c) 2022-2023 imacat.
 #
 #  Licensed under the Apache License, Version 2.0 (the "License");
 #  you may not use this file except in compliance with the License.
@@ -15,6 +15,43 @@
 #  See the License for the specific language governing permissions and
 #  limitations under the License.
 
+[project]
+name = "Flask-DigestAuth"
+dynamic = ["version"]
+description = "The Flask HTTP Digest Authentication project."
+readme = "README.rst"
+requires-python = ">=3.8"
+authors = [
+    {name = "imacat", email = "imacat@mail.imacat.idv.tw"},
+]
+keywords = ["flask", "digest-authentication"]
+classifiers = [
+    "Programming Language :: Python :: 3",
+    "License :: OSI Approved :: Apache Software License",
+    "Operating System :: OS Independent",
+    "Framework :: Flask",
+    "Topic :: System :: Systems Administration :: Authentication/Directory",
+    "Intended Audience :: Developers",
+]
+dependencies = [
+    "flask",
+]
+
+[project.optional-dependencies]
+test = [
+    "unittest",
+    "flask-testing",
+]
+
+[project.urls]
+"Documentation" = "https://flask-digestauth.readthedocs.io"
+"Change Log" = "https://mia-accounting.readthedocs.io/en/latest/changelog.html"
+"Repository" = "https://github.com/imacat/flask-digestauth"
+"Bug Tracker" = "https://github.com/imacat/flask-digestauth/issues"
+
 [build-system]
 requires = ["setuptools>=42"]
 build-backend = "setuptools.build_meta"
+
+[tool.setuptools.dynamic]
+version = {attr = "flask_digest_auth.VERSION"}

setup.cfg

@@ -1,53 +0,0 @@
-# The Flask HTTP Digest Authentication Project.
-# Author: imacat@mail.imacat.idv.tw (imacat), 2022/11/23
-
-#  Copyright (c) 2022 imacat.
-#
-#  Licensed under the Apache License, Version 2.0 (the "License");
-#  you may not use this file except in compliance with the License.
-#  You may obtain a copy of the License at
-#
-#      http://www.apache.org/licenses/LICENSE-2.0
-#
-#  Unless required by applicable law or agreed to in writing, software
-#  distributed under the License is distributed on an "AS IS" BASIS,
-#  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-#  See the License for the specific language governing permissions and
-#  limitations under the License.
-
-[metadata]
-name = flask-digest-auth
-version = 0.2.1
-author = imacat
-author_email = imacat@mail.imacat.idv.tw
-description = The Flask HTTP Digest Authentication project.
-long_description = file: README.rst
-long_description_content_type = text/x-rst
-url = https://github.com/imacat/flask-digest-auth
-project_urls =
-    Bug Tracker = https://github.com/imacat/flask-digest-auth/issues
-classifiers =
-    Programming Language :: Python :: 3
-    License :: OSI Approved :: Apache Software License
-    Operating System :: OS Independent
-    Framework :: Flask
-    Topic :: System :: Systems Administration :: Authentication/Directory
-    Intended Audience :: Developers
-
-[options]
-package_dir =
-    = src
-packages = find:
-python_requires = >=3.7
-install_requires =
-  flask
-tests_require =
-  unittest
-  flask-testing
-
-[options.packages.find]
-where = src
-
-[options.extras_require]
-flask_login =
-    flask-login

src/flask_digest_auth/__init__.py

@@ -21,3 +21,6 @@
 from flask_digest_auth.algo import make_password_hash, calc_response
 from flask_digest_auth.auth import DigestAuth
 from flask_digest_auth.test import Client
+
+VERSION: str = "0.6.0"
+"""The package version."""

src/flask_digest_auth/algo.py

@@ -20,14 +20,19 @@
 """
 from __future__ import annotations
 
-import typing as t
 from hashlib import md5
-
-from flask_digest_auth.exception import UnauthorizedException
+from typing import Optional, Literal
 
 
 def make_password_hash(realm: str, username: str, password: str) -> str:
     """Calculates the password hash for the HTTP digest authentication.
+    Use this function to set the password for the user.
+
+    :Example:
+
+    ::
+
+        user.password = make_password_hash(realm, username, password)
 
     :param realm: The realm.
     :param username: The username.
@@ -39,48 +44,38 @@ def make_password_hash(realm: str, username: str, password: str) -> str:
 
 def calc_response(
         method: str, uri: str, password_hash: str,
-        nonce: str, qop: t.Optional[t.Literal["auth", "auth-int"]] = None,
-        algorithm: t.Optional[t.Literal["MD5", "MD5-sess"]] = "MD5-sess",
-        cnonce: t.Optional[str] = None, nc: t.Optional[str] = None,
-        body: t.Optional[bytes] = None) -> str:
+        nonce: str, qop: Optional[Literal["auth", "auth-int"]] = None,
+        algorithm: Optional[Literal["MD5", "MD5-sess"]] = "MD5-sess",
+        cnonce: Optional[str] = None, nc: Optional[str] = None,
+        body: Optional[bytes] = None) -> str:
     """Calculates the response value of the HTTP digest authentication.
 
     :param method: The request method.
     :param uri: The request URI.
     :param password_hash: The password hash for the HTTP digest authentication.
     :param nonce: The nonce.
-    :param qop: the quality of protection.
-    :param algorithm: The algorithm, either "MD5" or "MD5-sess".
+    :param qop: The quality of protection, either ``auth`` or ``auth-int``.
+    :param algorithm: The algorithm, either ``MD5`` or ``MD5-sess``.
     :param cnonce: The client nonce, which must exists when qop exists or
-        algorithm="MD5-sess".
+        algorithm is ``MD5-sess``.
     :param nc: The request counter, which must exists when qop exists.
-    :param body: The request body, which must exists when qop="auth-int".
+    :param body: The request body, which must exists when qop is ``auth-int``.
     :return: The response value.
-    :raise UnauthorizedException: When the cnonce is missing with the MD5-sess
-        algorithm, when the body is missing with the auth-int qop, or when the
-        cnonce or nc is missing with the auth or auth-int qop.
+    :raise AssertionError: When cnonce is missing with algorithm is
+        ``MD5-sess``, when body is missing with qop is ``auth-int``, or when
+        cnonce or nc is missing with qop exits.
     """
 
-    def validate_required(field: t.Optional[str], error: str) -> None:
-        """Validates a required field.
-
-        :param field: The field that is required.
-        :param error: The error message.
-        :return: None.
-        """
-        if field is None:
-            raise UnauthorizedException(error)
-
     def calc_ha1() -> str:
         """Calculates and returns the first hash.
 
         :return: The first hash.
-        :raise UnauthorizedException: When the cnonce is missing with the MD5-sess
-            algorithm.
+        :raise AssertionError: When cnonce is missing with
+            algorithm is ``MD5-sess``.
         """
         if algorithm == "MD5-sess":
-            validate_required(
-                cnonce, f"Missing \"cnonce\" with algorithm=\"{algorithm}\"")
+            assert cnonce is not None,\
+                f"Missing \"cnonce\" with algorithm=\"{algorithm}\""
             return md5(f"{password_hash}:{nonce}:{cnonce}".encode("utf8")) \
                 .hexdigest()
         # algorithm is None or algorithm == "MD5"
@@ -90,11 +85,10 @@ def calc_response(
         """Calculates the second hash.
 
         :return: The second hash.
-        :raise UnauthorizedException: When the body is missing with
-            qop="auth-int".
+        :raise AssertionError: When body is missing with qop is ``auth-int``.
         """
         if qop == "auth-int":
-            validate_required(body, f"Missing \"body\" with qop=\"{qop}\"")
+            assert body is not None, f"Missing \"body\" with qop=\"{qop}\""
             return md5(
                 f"{method}:{uri}:{md5(body).hexdigest()}".encode("utf8")) \
                 .hexdigest()
@@ -104,8 +98,8 @@ def calc_response(
     ha1: str = calc_ha1()
     ha2: str = calc_ha2()
     if qop == "auth" or qop == "auth-int":
-        validate_required(cnonce, f"Missing \"cnonce\" with the qop=\"{qop}\"")
-        validate_required(nc, f"Missing \"nc\" with the qop=\"{qop}\"")
+        assert cnonce is not None, f"Missing \"cnonce\" with the qop=\"{qop}\""
+        assert nc is not None, f"Missing \"nc\" with the qop=\"{qop}\""
         return md5(f"{ha1}:{nonce}:{nc}:{cnonce}:{qop}:{ha2}".encode("utf8"))\
             .hexdigest()
     # qop is None

src/flask_digest_auth/auth.py

@@ -1,7 +1,7 @@
 # The Flask HTTP Digest Authentication Project.
 # Author: imacat@mail.imacat.idv.tw (imacat), 2022/10/22
 
-#  Copyright (c) 2022 imacat.
+#  Copyright (c) 2022-2023 imacat.
 #
 #  Licensed under the Apache License, Version 2.0 (the "License");
 #  you may not use this file except in compliance with the License.
@@ -16,101 +16,79 @@
 #  limitations under the License.
 
 """The HTTP Digest Authentication.
-See RFC 2617 HTTP Authentication: Basic and Digest Access Authentication
+See `RFC 2617`_ HTTP Authentication: Basic and Digest Access Authentication
 
+.. _RFC 2617: https://www.rfc-editor.org/rfc/rfc2617
 """
 from __future__ import annotations
 
 import sys
-import typing as t
 from functools import wraps
 from secrets import token_urlsafe, randbits
+from typing import Any, Optional, Literal, Callable, List
 
-from flask import g, request, Response, session, abort, Flask, Request
+from flask import g, request, Response, session, abort, Flask, Request, \
+    current_app
 from itsdangerous import URLSafeTimedSerializer, BadData
 from werkzeug.datastructures import Authorization
 
 from flask_digest_auth.algo import calc_response
-from flask_digest_auth.exception import UnauthorizedException
-
-
-class BasePasswordHashGetter:
-    """The base password hash getter."""
-
-    @staticmethod
-    def __call__(username: str) -> t.Optional[str]:
-        """Returns the password hash of a user.
-
-        :param username: The username.
-        :return: The password hash, or None if the user does not exist.
-        :raise UnboundLocalError: When the password hash getter function is
-            not registered yet.
-        """
-        raise UnboundLocalError("The function to return the password hash"
-                                " was not registered yet.")
-
-
-class BaseUserGetter:
-    """The base user getter."""
-
-    @staticmethod
-    def __call__(username: str) -> t.Optional[t.Any]:
-        """Returns a user.
-
-        :param username: The username.
-        :return: The user, or None if the user does not exist.
-        :raise UnboundLocalError: When the user getter function is not
-            registered yet.
-        """
-        raise UnboundLocalError("The function to return the user"
-                                " was not registered yet.")
-
-
-class BaseOnLogInCallback:
-    """The base callback when the user logs in."""
-
-    @staticmethod
-    def __call__(user: t.Any) -> None:
-        """Runs the callback when the user logs in.
-
-        :param user: The logged-in user.
-        :return: None.
-        """
 
 
 class DigestAuth:
     """The HTTP digest authentication."""
 
-    def __init__(self, realm: t.Optional[str] = None):
+    def __init__(self, realm: Optional[str] = None):
         """Constructs the HTTP digest authentication.
 
         :param realm: The realm.
         """
-        self.secret_key: str = token_urlsafe(32)
-        self.serializer: URLSafeTimedSerializer \
-            = URLSafeTimedSerializer(self.secret_key)
-        self.realm: str = "" if realm is None else realm
-        self.algorithm: t.Optional[str] = None
+        self.__serializer: URLSafeTimedSerializer \
+            = URLSafeTimedSerializer(token_urlsafe(32))
+        """The serializer to generate and validate the nonce and opaque."""
+        self.realm: str = "Login Required" if realm is None else realm
+        """The realm.  Default is "Login Required"."""
+        self.algorithm: Optional[Literal["MD5", "MD5-sess"]] = None
+        """The algorithm, either None, ``MD5``, or ``MD5-sess``.  Default is
+        None."""
         self.use_opaque: bool = True
-        self.domain: t.List[str] = []
-        self.qop: t.List[str] = ["auth", "auth-int"]
-        self.app: t.Optional[Flask] = None
+        """Whether to use an opaque.  Default is True."""
+        self.__domain: List[str] = []
+        """A list of directories that this username and password applies to.
+        Default is empty."""
+        self.__qop: List[Literal["auth", "auth-int"]] = ["auth", "auth-int"]
+        """A list of supported quality of protection supported, either
+        ``qop``, ``auth-int``, both, or empty.  Default is both."""
         self.__get_password_hash: BasePasswordHashGetter \
             = BasePasswordHashGetter()
+        """The callback to return the password hash."""
         self.__get_user: BaseUserGetter = BaseUserGetter()
+        """The callback to return the user."""
         self.__on_login: BaseOnLogInCallback = BaseOnLogInCallback()
+        """The callback to run when the user logs in."""
 
-    def login_required(self, view) -> t.Callable:
-        """The view decorator for HTTP digest authentication.
+    def login_required(self, view) -> Callable:
+        """The view decorator for the HTTP digest authentication.
 
-        :param view:
+        :Example:
+
+        ::
+
+            @app.get("/admin")
+            @auth.login_required
+            def admin():
+                return f"Hello, {g.user.username}!"
+
+        The logged-in user can be retrieved at ``g.user``.
+
+        :param view: The view.
         :return: The login-protected view.
         """
 
         class NoLogInException(Exception):
             """The exception thrown when the user is not authorized."""
 
-        def get_logged_in_user() -> t.Any:
+        def get_logged_in_user() -> Any:
             """Returns the currently logged-in user.
 
             :return: The currently logged-in user.
@@ -118,13 +96,13 @@ class DigestAuth:
             """
             if "user" not in session:
                 raise NoLogInException
-            user: t.Optional[t.Any] = self.__get_user(session["user"])
+            user: Optional[Any] = self.__get_user(session["user"])
             if user is None:
                 del session["user"]
                 raise NoLogInException
             return user
 
-        def auth_user(state: AuthState) -> t.Any:
+        def auth_user(state: AuthState) -> Any:
             """Authenticates a user.
 
             :param state: The authentication state.
@@ -137,12 +115,12 @@ class DigestAuth:
             if authorization.type != "digest":
                 raise UnauthorizedException(
                     "Not an HTTP digest authorization")
-            self.authenticate(state)
+            self.__authenticate(state)
             session["user"] = authorization.username
             return self.__get_user(authorization.username)
 
         @wraps(view)
-        def login_required_view(*args, **kwargs) -> t.Any:
+        def login_required_view(*args, **kwargs) -> Any:
             """The login-protected view.
 
             :param args: The positional arguments of the view.
@@ -166,12 +144,12 @@ class DigestAuth:
                 response: Response = Response()
                 response.status = 401
                 response.headers["WWW-Authenticate"] \
-                    = self.make_response_header(state)
+                    = self.__make_response_header(state)
                 abort(response)
 
         return login_required_view
 
-    def authenticate(self, state: AuthState) -> None:
+    def __authenticate(self, state: AuthState) -> None:
         """Authenticate a user.
 
         :param state: The authorization state.
@@ -187,12 +165,12 @@ class DigestAuth:
                 raise UnauthorizedException(
                     "Missing \"opaque\" in the Authorization header")
             try:
-                self.serializer.loads(
+                self.__serializer.loads(
                     authorization.opaque, salt="opaque", max_age=1800)
             except BadData:
                 raise UnauthorizedException("Invalid opaque")
             state.opaque = authorization.opaque
-        password_hash: t.Optional[str] \
+        password_hash: Optional[str] \
             = self.__get_password_hash(authorization.username)
         if password_hash is None:
             raise UnauthorizedException(
@@ -208,7 +186,7 @@ class DigestAuth:
             state.stale = False
             raise UnauthorizedException("Incorrect response value")
         try:
-            self.serializer.loads(
+            self.__serializer.loads(
                 authorization.nonce,
                 salt="nonce" if authorization.opaque is None
                 else f"nonce-{authorization.opaque}")
@@ -216,14 +194,14 @@ class DigestAuth:
             state.stale = True
             raise UnauthorizedException("Invalid nonce")
 
-    def make_response_header(self, state: AuthState) -> str:
-        """Composes and returns the WWW-Authenticate response header.
+    def __make_response_header(self, state: AuthState) -> str:
+        """Composes and returns the ``WWW-Authenticate`` response header.
 
         :param state: The authorization state.
-        :return: The WWW-Authenticate response header.
+        :return: The ``WWW-Authenticate`` response header.
         """
 
-        def get_opaque() -> t.Optional[str]:
+        def get_opaque() -> Optional[str]:
             """Returns the opaque value.
 
             :return: The opaque value.
@@ -232,32 +210,41 @@ class DigestAuth:
                 return None
             if state.opaque is not None:
                 return state.opaque
-            return self.serializer.dumps(randbits(32), salt="opaque")
+            return self.__serializer.dumps(randbits(32), salt="opaque")
 
-        opaque: t.Optional[str] = get_opaque()
-        nonce: str = self.serializer.dumps(
+        opaque: Optional[str] = get_opaque()
+        nonce: str = self.__serializer.dumps(
             randbits(32),
             salt="nonce" if opaque is None else f"nonce-{opaque}")
 
         header: str = f"Digest realm=\"{self.realm}\""
-        if len(self.domain) > 0:
-            domain_list: str = ",".join(self.domain)
+        if len(self.__domain) > 0:
+            domain_list: str = ",".join(self.__domain)
             header += f", domain=\"{domain_list}\""
         header += f", nonce=\"{nonce}\""
         if opaque is not None:
             header += f", opaque=\"{opaque}\""
         if state.stale is not None:
-            header += f", stale=TRUE" if state.stale else f", stale=FALSE"
+            header += ", stale=TRUE" if state.stale else ", stale=FALSE"
         if self.algorithm is not None:
             header += f", algorithm=\"{self.algorithm}\""
-        if len(self.qop) > 0:
-            qop_list: str = ",".join(self.qop)
+        if len(self.__qop) > 0:
+            qop_list: str = ",".join(self.__qop)
             header += f", qop=\"{qop_list}\""
         return header
 
-    def register_get_password(self, func: t.Callable[[str], t.Optional[str]])\
+    def register_get_password(self, func: Callable[[str], Optional[str]]) \
             -> None:
-        """Registers the callback to obtain the password hash.
+        """The decorator to register the callback to obtain the password hash.
+
+        :Example:
+
+        ::
+
+            @auth.register_get_password
+            def get_password_hash(username: str) -> Optional[str]:
+                user = User.query.filter(User.username == username).first()
+                return None if user is None else user.password
 
         :param func: The callback that given the username, returns the password
             hash, or None if the user does not exist.
@@ -268,7 +255,7 @@ class DigestAuth:
             """The base password hash getter."""
 
             @staticmethod
-            def __call__(username: str) -> t.Optional[str]:
+            def __call__(username: str) -> Optional[str]:
                 """Returns the password hash of a user.
 
                 :param username: The username.
@@ -278,9 +265,16 @@ class DigestAuth:
 
         self.__get_password_hash = PasswordHashGetter()
 
-    def register_get_user(self, func: t.Callable[[str], t.Optional[t.Any]])\
-            -> None:
-        """Registers the callback to obtain the user.
+    def register_get_user(self, func: Callable[[str], Optional[Any]]) -> None:
+        """The decorator to register the callback to obtain the user.
+
+        :Example:
+
+        ::
+
+            @auth.register_get_user
+            def get_user(username: str) -> Optional[User]:
+                return User.query.filter(User.username == username).first()
 
         :param func: The callback that given the username, returns the user,
             or None if the user does not exist.
@@ -291,7 +285,7 @@ class DigestAuth:
             """The user getter."""
 
             @staticmethod
-            def __call__(username: str) -> t.Optional[t.Any]:
+            def __call__(username: str) -> Optional[Any]:
                 """Returns a user.
 
                 :param username: The username.
@@ -301,8 +295,16 @@ class DigestAuth:
 
         self.__get_user = UserGetter()
 
-    def register_on_login(self, func: t.Callable[[t.Any], None]) -> None:
-        """Registers the callback when the user logs in.
+    def register_on_login(self, func: Callable[[Any], None]) -> None:
+        """The decorator to register the callback to run when the user logs in.
+
+        :Example:
+
+        ::
+
+            @auth.register_on_login
+            def on_login(user: User) -> None:
+                user.visits = user.visits + 1
 
         :param func: The callback given the logged-in user.
         :return: None.
@@ -312,7 +314,7 @@ class DigestAuth:
             """The callback when the user logs in."""
 
             @staticmethod
-            def __call__(user: t.Any) -> None:
+            def __call__(user: Any) -> None:
                 """Runs the callback when the user logs in.
 
                 :param user: The logged-in user.
@@ -323,69 +325,98 @@ class DigestAuth:
         self.__on_login = OnLogInCallback()
 
     def init_app(self, app: Flask) -> None:
-        """Initializes the Flask application.
+        """Initializes the Flask application.  The DigestAuth instance will
+        be stored in ``app.extensions["digest_auth"]``.
+
+        :Example:
+
+        ::
+
+            app: flask = Flask(__name__)
+            auth: DigestAuth = DigestAuth()
+            auth.init_app(app)
 
         :param app: The Flask application.
         :return: None.
         """
-        app.digest_auth = self
-        self.app = app
+        app.extensions["digest_auth"] = self
+        if "DIGEST_AUTH_REALM" in app.config:
+            self.realm = app.config["DIGEST_AUTH_REALM"]
 
         if hasattr(app, "login_manager"):
-            from flask_login import LoginManager, login_user
+            self.__init_login_manager(app)
 
-            login_manager: LoginManager = getattr(app, "login_manager")
+    def __init_login_manager(self, app: Flask) -> None:
+        """Initializes the Flask-Login login manager.
 
-            @login_manager.unauthorized_handler
-            def unauthorized() -> None:
-                """Handles when the user is unauthorized.
+        :param app: The Flask application.
+        :return: None.
+        """
+        from flask_login import LoginManager, login_user
+        login_manager: LoginManager = getattr(app, "login_manager")
 
-                :return: None.
-                """
-                response: Response = Response()
-                response.status = 401
-                response.headers["WWW-Authenticate"] \
-                    = self.make_response_header(g.digest_auth_state)
-                abort(response)
+        @login_manager.unauthorized_handler
+        def unauthorized() -> None:
+            """Handles when the user is unauthorized.
 
-            @login_manager.request_loader
-            def load_user_from_request(req: Request) -> t.Optional[t.Any]:
-                """Loads the user from the request header.
+            :return: None.
+            """
+            state: AuthState = getattr(request, "_digest_auth_state") \
+                if hasattr(request, "_digest_auth_state") \
+                else AuthState()
+            response: Response = Response()
+            response.status = 401
+            response.headers["WWW-Authenticate"] \
+                = self.__make_response_header(state)
+            abort(response)
 
-                :param req: The request.
-                :return: The authenticated user, or None if the
-                    authentication fails
-                """
-                g.digest_auth_state = AuthState()
-                authorization: Authorization = req.authorization
-                try:
-                    if authorization is None:
-                        raise UnauthorizedException
-                    if authorization.type != "digest":
-                        raise UnauthorizedException(
-                            "Not an HTTP digest authorization")
-                    self.authenticate(g.digest_auth_state)
-                    user = login_manager.user_callback(
-                        authorization.username)
-                    login_user(user)
-                    self.__on_login(user)
-                    return user
-                except UnauthorizedException as e:
-                    if str(e) != "":
-                        app.logger.warning(str(e))
-                    return None
+        @login_manager.request_loader
+        def load_user_from_request(req: Request) -> Optional[Any]:
+            """Loads the user from the request header.
+
+            :param req: The request.
+            :return: The authenticated user, or None if the
+                authentication fails
+            """
+            request._digest_auth_state = AuthState()
+            authorization: Authorization = req.authorization
+            try:
+                if authorization is None:
+                    raise UnauthorizedException
+                if authorization.type != "digest":
+                    raise UnauthorizedException(
+                        "Not an HTTP digest authorization")
+                self.__authenticate(request._digest_auth_state)
+                user = login_manager.user_callback(authorization.username)
+                login_user(user)
+                self.__on_login(user)
+                return user
+            except UnauthorizedException as e:
+                if str(e) != "":
+                    app.logger.warning(str(e))
+                return None
 
     def logout(self) -> None:
         """Logs out the user.
         This actually causes the next authentication to fail, which forces
         the browser to ask the user for the username and password again.
 
+        :Example:
+
+        ::
+
+            @app.post("/logout")
+            @auth.login_required
+            def logout():
+                auth.logout()
+                return redirect(request.form.get("next"))
+
         :return: None.
         """
         if "user" in session:
             del session["user"]
         try:
-            if hasattr(self.app, "login_manager"):
+            if hasattr(current_app, "login_manager"):
                 from flask_login import logout_user
                 logout_user()
         except ModuleNotFoundError:
@@ -394,9 +425,76 @@ class DigestAuth:
 
 
 class AuthState:
-    """The authorization state."""
+    """The authentication state.  It keeps the status in the earlier
+    authentication stage, so that the latter response stage knows how to
+    response.
+    """
 
     def __init__(self):
         """Constructs the authorization state."""
-        self.opaque: t.Optional[str] = None
-        self.stale: t.Optional[bool] = None
+        self.opaque: Optional[str] = None
+        """The opaque value specified by the client, if valid."""
+        self.stale: Optional[bool] = None
+        """The stale value, if there is a previous log in attempt."""
+
+
+class UnauthorizedException(Exception):
+    """The exception thrown when the authentication fails."""
+
+
+class BasePasswordHashGetter:
+    """The base callback that given the username, returns the password hash,
+    or None if the user does not exist.  The default is to raise an
+    :class:`UnboundLocalError` if the callback is not registered yet.
+
+    See :meth:`flask_digest_auth.auth.DigestAuth.register_get_password`
+    """
+
+    @staticmethod
+    def __call__(username: str) -> Optional[str]:
+        """Returns the password hash of a user.
+
+        :param username: The username.
+        :return: The password hash, or None if the user does not exist.
+        :raise UnboundLocalError: When the password hash getter function is
+            not registered yet.
+        """
+        raise UnboundLocalError("The function to return the password hash"
+                                " was not registered yet.")
+
+
+class BaseUserGetter:
+    """The base callback that given the username, returns the user, or None if
+    the user does not exist.  The default is to raise an
+    :class:`UnboundLocalError` if the callback is not registered yet.
+
+    See :meth:`flask_digest_auth.auth.DigestAuth.register_get_user`
+    """
+
+    @staticmethod
+    def __call__(username: str) -> Optional[Any]:
+        """Returns a user.
+
+        :param username: The username.
+        :return: The user, or None if the user does not exist.
+        :raise UnboundLocalError: When the user getter function is not
+            registered yet.
+        """
+        raise UnboundLocalError("The function to return the user"
+                                " was not registered yet.")
+
+
+class BaseOnLogInCallback:
+    """The base callback to run when the user logs in, given the logged-in
+    user.  The default does nothing.
+
+    See :meth:`flask_digest_auth.auth.DigestAuth.register_on_login`
+    """
+
+    @staticmethod
+    def __call__(user: Any) -> None:
+        """Runs the callback when the user logs in.
+
+        :param user: The logged-in user.
+        :return: None.
+        """

src/flask_digest_auth/exception.py

@@ -1,25 +0,0 @@
-# The Flask HTTP Digest Authentication Project.
-# Author: imacat@mail.imacat.idv.tw (imacat), 2022/11/3
-
-#  Copyright (c) 2022 imacat.
-#
-#  Licensed under the Apache License, Version 2.0 (the "License");
-#  you may not use this file except in compliance with the License.
-#  You may obtain a copy of the License at
-#
-#      http://www.apache.org/licenses/LICENSE-2.0
-#
-#  Unless required by applicable law or agreed to in writing, software
-#  distributed under the License is distributed on an "AS IS" BASIS,
-#  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-#  See the License for the specific language governing permissions and
-#  limitations under the License.
-
-"""The exception.
-
-"""
-
-
-class UnauthorizedException(Exception):
-    """The exception thrown when the authentication is failed."""
-    pass

src/flask_digest_auth/test.py

@@ -18,8 +18,8 @@
 """The test client with HTTP digest authentication enabled.
 
 """
-import typing as t
 from secrets import token_urlsafe
+from typing import Optional, Literal, Tuple, Dict
 
 from flask import g
 from werkzeug.datastructures import Authorization, WWWAuthenticate
@@ -29,15 +29,67 @@ from flask_digest_auth.algo import calc_response, make_password_hash
 
 
 class Client(WerkzeugClient):
-    """The test client with HTTP digest authentication enabled."""
+    """The test client with HTTP digest authentication enabled.
 
-    def open(self, *args, digest_auth: t.Optional[t.Tuple[str, str]] = None,
+    :Example:
+
+    For unittest_:
+
+    ::
+
+        class MyTestCase(flask_testing.TestCase):
+
+            def create_app(self):
+                app: Flask = create_app({
+                    "SECRET_KEY": token_urlsafe(32),
+                    "TESTING": True
+                })
+                app.test_client_class = Client
+                return app
+
+            def test_admin(self):
+                response = self.client.get("/admin")
+                self.assertEqual(response.status_code, 401)
+                response = self.client.get(
+                    "/admin", digest_auth=(USERNAME, PASSWORD))
+                self.assertEqual(response.status_code, 200)
+
+    For pytest_:
+
+    ::
+
+        @pytest.fixture()
+        def app():
+            app: Flask = create_app({
+                "SECRET_KEY": token_urlsafe(32),
+                "TESTING": True
+            })
+            app.test_client_class = Client
+            yield app
+
+        @pytest.fixture()
+        def client(app):
+            return app.test_client()
+
+        def test_admin(app: Flask, client: Client):
+            with app.app_context():
+                response = client.get("/admin")
+                assert response.status_code == 401
+                response = client.get(
+                    "/admin", digest_auth=(USERNAME, PASSWORD))
+                assert response.status_code == 200
+
+    .. _unittest: https://docs.python.org/3/library/unittest.html
+    .. _pytest: https://pytest.org
+    """
+
+    def open(self, *args, digest_auth: Optional[Tuple[str, str]] = None,
              **kwargs) -> TestResponse:
         """Opens a request.
 
         :param args: The arguments.
-        :param digest_auth: The username and password for the HTTP digest
-            authentication.
+        :param digest_auth: The (*username*, *password*) tuple for the HTTP
+            digest authentication.
         :param kwargs: The keyword arguments.
         :return: The response.
         """
@@ -59,20 +111,20 @@ class Client(WerkzeugClient):
                            username: str, password: str) -> Authorization:
         """Composes and returns the request authorization.
 
-        :param www_authenticate: The WWW-Authenticate response.
+        :param www_authenticate: The ``WWW-Authenticate`` response.
         :param uri: The request URI.
         :param username: The username.
         :param password: The password.
         :return: The request authorization.
         """
-        qop: t.Optional[t.Literal["auth", "auth-int"]] = None
+        qop: Optional[Literal["auth", "auth-int"]] = None
         if www_authenticate.qop is not None and "auth" in www_authenticate.qop:
             qop = "auth"
 
-        cnonce: t.Optional[str] = None
+        cnonce: Optional[str] = None
         if qop is not None or www_authenticate.algorithm == "MD5-sess":
             cnonce = token_urlsafe(8)
-        nc: t.Optional[str] = None
+        nc: Optional[str] = None
         count: int = 1
         if qop is not None:
             nc: str = hex(count)[2:].zfill(8)
@@ -85,7 +137,7 @@ class Client(WerkzeugClient):
             algorithm=www_authenticate.algorithm, cnonce=cnonce, nc=nc,
             body=None)
 
-        data: t.Dict[str, str] = {
+        data: Dict[str, str] = {
             "username": username, "realm": www_authenticate.realm,
             "nonce": www_authenticate.nonce, "uri": uri, "response": expected}
         if www_authenticate.algorithm is not None:

tests/test_algo.py

@@ -18,8 +18,8 @@
 """The test case for the HTTP digest authentication algorithm.
 
 """
-import typing as t
 import unittest
+from typing import Optional, Literal
 
 from flask_digest_auth import make_password_hash, calc_response
 
@@ -39,11 +39,11 @@ class AlgorithmTestCase(unittest.TestCase):
         method: str = "GET"
         uri: str = "/dir/index.html"
         nonce: str = "dcd98b7102dd2f0e8b11d0f600bfb0c093"
-        qop: t.Optional[t.Literal["auth", "auth-int"]] = "auth"
-        algorithm: t.Optional[t.Literal["MD5", "MD5-sess"]] = None
-        cnonce: t.Optional[str] = "0a4f113b"
-        nc: t.Optional[str] = "00000001"
-        body: t.Optional[bytes] = None
+        qop: Optional[Literal["auth", "auth-int"]] = "auth"
+        algorithm: Optional[Literal["MD5", "MD5-sess"]] = None
+        cnonce: Optional[str] = "0a4f113b"
+        nc: Optional[str] = "00000001"
+        body: Optional[bytes] = None
 
         password_hash: str = make_password_hash(realm, username, password)
         response: str = calc_response(method, uri, password_hash, nonce, qop,

tests/test_auth.py

@@ -1,7 +1,7 @@
 # The Flask HTTP Digest Authentication Project.
 # Author: imacat@mail.imacat.idv.tw (imacat), 2022/10/22
 
-#  Copyright (c) 2022 imacat.
+#  Copyright (c) 2022-2023 imacat.
 #
 #  Licensed under the Apache License, Version 2.0 (the "License");
 #  you may not use this file except in compliance with the License.
@@ -18,8 +18,8 @@
 """The test case for the HTTP digest authentication.
 
 """
-import typing as t
 from secrets import token_urlsafe
+from typing import Any, Optional, Dict
 
 from flask import Response, Flask, g, redirect, request
 from flask_testing import TestCase
@@ -57,18 +57,19 @@ class AuthenticationTestCase(TestCase):
         """
         app: Flask = Flask(__name__)
         app.config.from_mapping({
+            "TESTING": True,
             "SECRET_KEY": token_urlsafe(32),
-            "TESTING": True
+            "DIGEST_AUTH_REALM": _REALM,
         })
         app.test_client_class = Client
 
-        auth: DigestAuth = DigestAuth(realm=_REALM)
+        auth: DigestAuth = DigestAuth()
         auth.init_app(app)
         self.user: User = User(_USERNAME, _PASSWORD)
-        user_db: t.Dict[str, User] = {_USERNAME: self.user}
+        user_db: Dict[str, User] = {_USERNAME: self.user}
 
         @auth.register_get_password
-        def get_password_hash(username: str) -> t.Optional[str]:
+        def get_password_hash(username: str) -> Optional[str]:
             """Returns the password hash of a user.
 
             :param username: The username.
@@ -78,7 +79,7 @@ class AuthenticationTestCase(TestCase):
                 else None
 
         @auth.register_get_user
-        def get_user(username: str) -> t.Optional[t.Any]:
+        def get_user(username: str) -> Optional[Any]:
             """Returns a user.
 
             :param username: The username.

tests/test_flask_login.py

@@ -1,7 +1,7 @@
 # The Flask HTTP Digest Authentication Project.
 # Author: imacat@mail.imacat.idv.tw (imacat), 2022/11/23
 
-#  Copyright (c) 2022 imacat.
+#  Copyright (c) 2022-2023 imacat.
 #
 #  Licensed under the Apache License, Version 2.0 (the "License");
 #  you may not use this file except in compliance with the License.
@@ -18,8 +18,8 @@
 """The test case for the Flask-Login integration.
 
 """
-import typing as t
 from secrets import token_urlsafe
+from typing import Optional, Dict
 
 from flask import Response, Flask, g, redirect, request
 from flask_testing import TestCase
@@ -45,7 +45,6 @@ class User:
         self.password_hash: str = make_password_hash(
             _REALM, username, password)
         self.visits: int = 0
-        self.is_authenticated: bool = True
         self.is_active: bool = True
         self.is_anonymous: bool = False
 
@@ -57,6 +56,16 @@ class User:
         """
         return self.username
 
+    @property
+    def is_authenticated(self) -> bool:
+        """Returns whether the user is authenticated.
+        This is required by Flask-Login.
+        This should return self.is_active.
+
+        :return: True if the user is active, or False otherwise.
+        """
+        return self.is_active
+
 
 class FlaskLoginTestCase(TestCase):
     """The test case with the Flask-Login integration."""
@@ -68,8 +77,9 @@ class FlaskLoginTestCase(TestCase):
         """
         app: Flask = Flask(__name__)
         app.config.from_mapping({
+            "TESTING": True,
             "SECRET_KEY": token_urlsafe(32),
-            "TESTING": True
+            "DIGEST_AUTH_REALM": _REALM,
         })
         app.test_client_class = Client
 
@@ -83,14 +93,14 @@ class FlaskLoginTestCase(TestCase):
         login_manager: flask_login.LoginManager = flask_login.LoginManager()
         login_manager.init_app(app)
 
-        auth: DigestAuth = DigestAuth(realm=_REALM)
+        auth: DigestAuth = DigestAuth()
         auth.init_app(app)
 
         self.user: User = User(_USERNAME, _PASSWORD)
-        user_db: t.Dict[str, User] = {_USERNAME: self.user}
+        user_db: Dict[str, User] = {_USERNAME: self.user}
 
         @auth.register_get_password
-        def get_password_hash(username: str) -> t.Optional[str]:
+        def get_password_hash(username: str) -> Optional[str]:
             """Returns the password hash of a user.
 
             :param username: The username.
@@ -109,7 +119,7 @@ class FlaskLoginTestCase(TestCase):
             user.visits = user.visits + 1
 
         @login_manager.user_loader
-        def load_user(user_id: str) -> t.Optional[User]:
+        def load_user(user_id: str) -> Optional[User]:
             """Loads a user.
 
             :param user_id: The username.
@@ -256,3 +266,34 @@ class FlaskLoginTestCase(TestCase):
         response = self.client.get(admin_uri)
         self.assertEqual(response.status_code, 200)
         self.assertEqual(self.user.visits, 2)
+
+    def test_disabled(self) -> None:
+        """Tests the disabled user.
+
+        :return: None.
+        """
+        if not self.has_flask_login:
+            self.skipTest("Skipped without Flask-Login.")
+
+        response: Response
+
+        self.user.is_active = False
+        response = self.client.get(self.app.url_for("admin-1"))
+        self.assertEqual(response.status_code, 401)
+        response = self.client.get(self.app.url_for("admin-1"),
+                                   digest_auth=(_USERNAME, _PASSWORD))
+        self.assertEqual(response.status_code, 401)
+
+        self.user.is_active = True
+        response = self.client.get(self.app.url_for("admin-1"),
+                                   digest_auth=(_USERNAME, _PASSWORD))
+        self.assertEqual(response.status_code, 200)
+        response = self.client.get(self.app.url_for("admin-1"))
+        self.assertEqual(response.status_code, 200)
+
+        self.user.is_active = False
+        response = self.client.get(self.app.url_for("admin-1"))
+        self.assertEqual(response.status_code, 401)
+        response = self.client.get(self.app.url_for("admin-1"),
+                                   digest_auth=(_USERNAME, _PASSWORD))
+        self.assertEqual(response.status_code, 401)