chrisroat/home.html

## home.html
<!DOCTYPE html>
<head>
    <title>Flask-Dance Multi-User SQLAlchemy</title>
</head>
<body>
{% with messages = get_flashed_messages(with_categories=true) %}
  {% if messages %}
    <ul class="flash">
    {% for category, message in messages %}
      <li class="{{ category }}">{{ message }}</li>
    {% endfor %}
    </ul>
  {% endif %}
{% endwith %}
{% if current_user.is_authenticated %}
  You are logged in as {{ current_user.name }}!
  <a href="{{ url_for("logout") }}">Log out</a>
{% else %}
  You are not logged in.
  <a href="{{ url_for("twitter.login") }}">Log in</a>
{% endif %}
</body>

## multi.py
import os
import sys
from flask import Flask, redirect, url_for, flash, render_template
from flask_sqlalchemy import SQLAlchemy
from sqlalchemy.orm.exc import NoResultFound
from flask_dance.contrib.twitter import make_twitter_blueprint, twitter
from flask_dance.consumer.backend.sqla import OAuthConsumerMixin, SQLAlchemyBackend
from flask_dance.consumer import oauth_authorized, oauth_error
from flask_login import (
    LoginManager, UserMixin, current_user,
    login_required, login_user, logout_user
)

# setup Flask application
app = Flask(__name__)
app.secret_key = "supersekrit"
blueprint = make_twitter_blueprint(
    api_key=os.environ['TWITTER_ID'],
    api_secret=os.environ['TWITTER_SECRET'],
)
app.register_blueprint(blueprint, url_prefix="/login")

# setup database models
app.config["SQLALCHEMY_DATABASE_URI"] = "sqlite:///multi.db"
db = SQLAlchemy()

class User(db.Model, UserMixin):
    id = db.Column(db.Integer, primary_key=True)
    name = db.Column(db.String(256), unique=True)

class OAuth(OAuthConsumerMixin, db.Model):
    provider_user_id = db.Column(db.String(256), unique=True)
    user_id = db.Column(db.Integer, db.ForeignKey(User.id))
    user = db.relationship(User)

# setup login manager
login_manager = LoginManager()
login_manager.login_view = 'twitter.login'

@login_manager.user_loader
def load_user(user_id):
    return User.query.get(int(user_id))

# setup SQLAlchemy backend
blueprint.backend = SQLAlchemyBackend(OAuth, db.session, user=current_user)

# create/login local user on successful OAuth login
@oauth_authorized.connect_via(blueprint)
def twitter_logged_in(blueprint, token):
    if not token:
        flash("Failed to log in.", category="error")
        return False

    resp = blueprint.session.get("account/settings.json")
    if not resp.ok:
        msg = "Failed to fetch user info."
        flash(msg, category="error")
        return False

    info = resp.json()
    user_id = str(info["screen_name"])

    # Find this OAuth token in the database, or create it
    query = OAuth.query.filter_by(
        provider=blueprint.name,
        provider_user_id=user_id,
    )
    try:
        oauth = query.one()
    except NoResultFound:
        oauth = OAuth(
            provider=blueprint.name,
            provider_user_id=user_id,
            token=token,
        )

    if oauth.user:
        login_user(oauth.user)
        flash("Successfully signed in.")

    else:
        # Create a new local user account for this user
        user = User(
            name=info["screen_name"],
        )
        # Associate the new local user account with the OAuth token
        oauth.user = user
        # Save and commit our database models
        db.session.add_all([user, oauth])
        db.session.commit()
        # Log in the new local user account
        login_user(user)
        flash("Successfully signed in.")

    # Disable Flask-Dance's default behavior for saving the OAuth token
    return False

# notify on OAuth provider error
@oauth_error.connect_via(blueprint)
def twitter_error(blueprint, error, error_description=None, error_uri=None):
    msg = (
        "OAuth error from {name}! "
        "error={error} description={description} uri={uri}"
    ).format(
        name=blueprint.name,
        error=error,
        description=error_description,
        uri=error_uri,
    )
    flash(msg, category="error")

@app.route("/logout")
@login_required
def logout():
    logout_user()
    flash("You have logged out")
    return redirect(url_for("index"))

@app.route("/")
def index():
    return render_template("home.html")

# hook up extensions to app
db.init_app(app)
login_manager.init_app(app)

if __name__ == "__main__":
    if "--setup" in sys.argv:
        with app.app_context():
            db.create_all()
            db.session.commit()
            print("Database tables created")
    else:
        app.run(debug=True)
	<!DOCTYPE html>
	<head>
	<title>Flask-Dance Multi-User SQLAlchemy</title>
	</head>
	<body>
	{% with messages = get_flashed_messages(with_categories=true) %}
	{% if messages %}
	<ul class="flash">
	{% for category, message in messages %}
	<li class="{{ category }}">{{ message }}</li>
	{% endfor %}
	</ul>
	{% endif %}
	{% endwith %}
	{% if current_user.is_authenticated %}
	You are logged in as {{ current_user.name }}!
	<a href="{{ url_for("logout") }}">Log out</a>
	{% else %}
	You are not logged in.
	<a href="{{ url_for("twitter.login") }}">Log in</a>
	{% endif %}
	</body>
	import os
	import sys
	from flask import Flask, redirect, url_for, flash, render_template
	from flask_sqlalchemy import SQLAlchemy
	from sqlalchemy.orm.exc import NoResultFound
	from flask_dance.contrib.twitter import make_twitter_blueprint, twitter
	from flask_dance.consumer.backend.sqla import OAuthConsumerMixin, SQLAlchemyBackend
	from flask_dance.consumer import oauth_authorized, oauth_error
	from flask_login import (
	LoginManager, UserMixin, current_user,
	login_required, login_user, logout_user
	)

	# setup Flask application
	app = Flask(__name__)
	app.secret_key = "supersekrit"
	blueprint = make_twitter_blueprint(
	api_key=os.environ['TWITTER_ID'],
	api_secret=os.environ['TWITTER_SECRET'],
	)
	app.register_blueprint(blueprint, url_prefix="/login")

	# setup database models
	app.config["SQLALCHEMY_DATABASE_URI"] = "sqlite:///multi.db"
	db = SQLAlchemy()

	class User(db.Model, UserMixin):
	id = db.Column(db.Integer, primary_key=True)
	name = db.Column(db.String(256), unique=True)

	class OAuth(OAuthConsumerMixin, db.Model):
	provider_user_id = db.Column(db.String(256), unique=True)
	user_id = db.Column(db.Integer, db.ForeignKey(User.id))
	user = db.relationship(User)

	# setup login manager
	login_manager = LoginManager()
	login_manager.login_view = 'twitter.login'

	@login_manager.user_loader
	def load_user(user_id):
	return User.query.get(int(user_id))

	# setup SQLAlchemy backend
	blueprint.backend = SQLAlchemyBackend(OAuth, db.session, user=current_user)

	# create/login local user on successful OAuth login
	@oauth_authorized.connect_via(blueprint)
	def twitter_logged_in(blueprint, token):
	if not token:
	flash("Failed to log in.", category="error")
	return False

	resp = blueprint.session.get("account/settings.json")
	if not resp.ok:
	msg = "Failed to fetch user info."
	flash(msg, category="error")
	return False

	info = resp.json()
	user_id = str(info["screen_name"])

	# Find this OAuth token in the database, or create it
	query = OAuth.query.filter_by(
	provider=blueprint.name,
	provider_user_id=user_id,
	)
	try:
	oauth = query.one()
	except NoResultFound:
	oauth = OAuth(
	provider=blueprint.name,
	provider_user_id=user_id,
	token=token,
	)

	if oauth.user:
	login_user(oauth.user)
	flash("Successfully signed in.")

	else:
	# Create a new local user account for this user
	user = User(
	name=info["screen_name"],
	)
	# Associate the new local user account with the OAuth token
	oauth.user = user
	# Save and commit our database models
	db.session.add_all([user, oauth])
	db.session.commit()
	# Log in the new local user account
	login_user(user)
	flash("Successfully signed in.")

	# Disable Flask-Dance's default behavior for saving the OAuth token
	return False

	# notify on OAuth provider error
	@oauth_error.connect_via(blueprint)
	def twitter_error(blueprint, error, error_description=None, error_uri=None):
	msg = (
	"OAuth error from {name}! "
	"error={error} description={description} uri={uri}"
	).format(
	name=blueprint.name,
	error=error,
	description=error_description,
	uri=error_uri,
	)
	flash(msg, category="error")

	@app.route("/logout")
	@login_required
	def logout():
	logout_user()
	flash("You have logged out")
	return redirect(url_for("index"))

	@app.route("/")
	def index():
	return render_template("home.html")

	# hook up extensions to app
	db.init_app(app)
	login_manager.init_app(app)

	if __name__ == "__main__":
	if "--setup" in sys.argv:
	with app.app_context():
	db.create_all()
	db.session.commit()
	print("Database tables created")
	else:
	app.run(debug=True)