Implement received Webmention handling

Add the Flask application setup, database models and migrations,
authentication, and configuration for development and testing.

Implement asynchronous Webmention verification with Huey, including HTML
and plain-text source validation, retries, status tracking, and size
limits.

Add status, login, and paginated received-Webmention views together with
comprehensive tests for forms, views, and receiver tasks.

1 files changed, 141 insertions, 0 deletions

diff --git a/webmentions_ssg/__init__.py b/webmentions_ssg/__init__.py
index 7f93695..f66e478 100644
--- a/webmentions_ssg/__init__.py
+++ b/webmentions_ssg/__init__.py
@@ -2,4 +2,145 @@
 #
 # SPDX-License-Identifier: BSD-3-Clause
 
+import logging
+import logging.handlers
+import os
+from pathlib import Path
+
+import click
+import coloredlogs
+import sqlalchemy as sa
+from flask import Flask
+from flask_bootstrap import Bootstrap5
+from flask_migrate import Migrate, upgrade
+from flask_sqlalchemy import SQLAlchemy
+from sqlalchemy.orm import DeclarativeBase
+
+from webmentions_ssg.config import DefaultConfig, DevelopmentConfig, ProductionConfig
+
+from .tasks import Huey
+
+APP_NAME = "webmentions-ssg"
 VERSION = "0.0.1"
+
+
+class Base(DeclarativeBase):
+    pass
+
+
+BOOTSTRAP = Bootstrap5()
+DATABASE = SQLAlchemy(model_class=Base)
+MIGRATE = Migrate()
+HUEY = Huey()
+
+
+def create_app(config_class: type[DefaultConfig] | None = None) -> Flask:
+    """Creates and configures the Flask application."""
+
+    development = os.environ.get(
+        "WEBMENTIONS_SSG_DEV",
+        "",
+    ).lower() in {
+        "1",
+        "true",
+        "yes",
+        "on",
+    }
+
+    if config_class is None:
+        config_class = DevelopmentConfig if development else ProductionConfig
+
+    app = Flask(
+        __name__,
+        instance_path=str(Path("testing").absolute()) if development else None,
+    )
+    app.config.from_object(config_class)
+
+    if not app.testing:
+        app.config.from_pyfile(app.config["CONFIG_FILE"], silent=True)
+        app.config.from_prefixed_env(prefix="FLASK")
+        app.config.from_prefixed_env(prefix="WEBMENTIONS_SSG")
+
+    default_logging_formatter = logging.Formatter(app.config["LOG_FORMAT"])
+
+    log_file_handler = logging.handlers.RotatingFileHandler(
+        app.config["LOG_FILE"],
+        maxBytes=app.config["LOGFILE_MAX_BYTES"],
+        backupCount=app.config["LOGFILE_BACKUP_COUNT"],
+    )
+    log_file_handler.setLevel(app.config["LOG_LEVEL"])
+    log_file_handler.setFormatter(default_logging_formatter)
+
+    logging.basicConfig(level=logging.DEBUG, handlers=[logging.NullHandler()])
+
+    app.logger.handlers.clear()
+    app.logger.setLevel(app.config["LOG_LEVEL"])
+    app.logger.addHandler(log_file_handler)
+
+    werkzeug_logger = logging.getLogger("werkzeug")
+    werkzeug_logger.setLevel(app.config["LOG_LEVEL"])
+    werkzeug_logger.addHandler(log_file_handler)
+
+    coloredlogs.install(
+        level=app.config["LOG_LEVEL"],
+        logger=app.logger,
+        fmt=app.config["LOG_FORMAT"],
+    )
+    coloredlogs.install(
+        level=app.config["LOG_LEVEL"],
+        logger=werkzeug_logger,
+        fmt=app.config["LOG_FORMAT"],
+    )
+
+    DATABASE.init_app(app)
+    MIGRATE.init_app(app, db=DATABASE)
+
+    from .auth import AUTH
+
+    AUTH.init_app(app)
+    BOOTSTRAP.init_app(app)
+    HUEY.init_app(app)
+
+    @app.context_processor
+    def inject_version():
+        return dict(VERSION=VERSION)
+
+    from .views import root_page
+
+    app.register_blueprint(root_page)
+
+    @app.cli.command("create-db")
+    def create_db() -> None:
+        """Create or update the database to the latest migration."""
+        upgrade()
+
+    @app.cli.command("create-user")
+    @click.argument("username")
+    @click.password_option(
+        confirmation_prompt=True,
+    )
+    def create_user(
+        username: str,
+        password: str,
+    ) -> None:
+        """Create a user."""
+
+        from .models import User
+
+        if (
+            DATABASE.session.scalar(sa.select(User).where(User.username == username))
+            is not None
+        ):
+            raise click.ClickException(f"User {username!r} already exists.")
+
+        user = User(
+            username=username,
+        )
+        user.set_password(password)
+
+        DATABASE.session.add(user)
+        DATABASE.session.commit()
+
+        click.echo(f"Created user {username!r}.")
+
+    return app