Add login functionality and basic HTML pages

code/app/__init__.py

@@ -1,10 +1,12 @@
 from flask import Flask
 from config import Config
 from flask_sqlalchemy import SQLAlchemy
+from flask_login import LoginManager
 
 app = Flask(__name__)
 app.config.from_object(Config)
 db = SQLAlchemy(app)
-
+login = LoginManager(app)
+login.login_view = "login"
 
 from app import routes, models

code/app/forms.py

@@ -0,0 +1,10 @@
+from flask_wtf import FlaskForm
+from wtforms import StringField, PasswordField, BooleanField, SubmitField
+from wtforms.validators import DataRequired
+
+
+class LoginForm(FlaskForm):
+    username = StringField("Username", validators=[DataRequired()])
+    password = PasswordField("Password", validators=[DataRequired()])
+    remember_me = BooleanField("Remember Me")
+    submit = SubmitField("Sign In")

code/app/models.py

@@ -1,16 +1,16 @@
-from app import db
-from subprocess import run
-from database.constants import DB_USER, DB_PW, DB_NAME
+from app import db, login
+from flask_login import UserMixin
+from werkzeug.security import check_password_hash
 
 
 class Glacier(db.Model):
-    uid = db.Column(db.String(5), primary_key=True)
+    id = db.Column(db.String(20), primary_key=True)
     country = db.Column(db.String(60))
     name = db.Column(db.String(60))
     annual_data = db.relationship("Annual_Data")
 
-    def __init__(self, uid, country, name):
-        self.uid = uid
+    def __init__(self, id, country, name):
+        self.id = id
         self.country = country
         self.name = name
 
@@ -18,7 +18,7 @@ class Glacier(db.Model):
 class Annual_Data(db.Model):
     __tablename__ = "annual_data"
     year = db.Column(db.Integer, primary_key=True)
-    uid = db.Column(db.ForeignKey("glacier.uid"), primary_key=True)
+    id = db.Column(db.ForeignKey("glacier.id"), primary_key=True)
     surface = db.Column(db.Float)
     length = db.Column(db.Float)
     elevation = db.Column(db.Float)
@@ -30,15 +30,22 @@ class Annual_Data(db.Model):
         self.elevation = elevation
 
 
-class User(db.Model):
-    uid = db.Column(db.Integer, primary_key=True)
+class User(UserMixin, db.Model):
+    id = db.Column(db.Integer, primary_key=True)
     registration_date = db.Column(
         db.DateTime, nullable=False, server_default=db.func.now()
     )
     username = db.Column(db.String(20), nullable=False, unique=True)
-    password = db.Column(db.String(60))
+    password_hash = db.Column(db.String(128), unique=True)
 
-    def __init__(self, uid, username, password):
-        self.uid = uid
+    def __init__(self, id, username, password_hash):
+        self.id = id
         self.username = username
-        self.password = password
+        self.password_hash = password_hash
+
+    def check_password(self, password):
+        return check_password_hash(self.password_hash, password)
+
+    @login.user_loader
+    def load_user(id):
+        return User.query.get(int(id))

code/app/routes.py

@@ -1,13 +1,42 @@
 from app import app
-from flask import render_template
+from app.forms import LoginForm
+from app.models import User
+from flask import flash, redirect, render_template, url_for, request
+from flask_login import current_user, login_user, logout_user, login_required
+from werkzeug.urls import url_parse
 
 
 @app.route("/")
 @app.route("/index")
 def index():
-    user = {"username": "Bolaji"}
-    posts = [
-        {"author": {"username": "Miloud"}, "body": "Beautiful day in Meknes!"},
-        {"author": {"username": "Sebtaoui"}, "body": "The Farkouss movie was lit!"},
-    ]
-    return render_template("index.html", title="Home", user=user, posts=posts)
+    return render_template("index.html", title="Home Page")
+
+
+@app.route("/login", methods=["GET", "POST"])
+def login():
+    if current_user.is_authenticated:
+        return redirect(url_for("admin"))
+    form = LoginForm()
+    if form.validate_on_submit():
+        user = User.query.filter_by(username=form.username.data).first()
+        if user is None or not user.check_password(form.password.data):
+            flash("Invalid username or password")
+            return redirect(url_for("login"))
+        login_user(user, remember=form.remember_me.data)
+        next_page = request.args.get("next")
+        if not next_page or url_parse(next_page).netloc != "":
+            next_page = url_for("admin")
+        return redirect(next_page)
+    return render_template("login.html", title="Sign In", form=form)
+
+
+@app.route("/logout")
+def logout():
+    logout_user()
+    return redirect(url_for("index"))
+
+
+@app.route("/admin")
+@login_required
+def admin():
+    return render_template("admin.html", title="Admin Page")

code/app/templates/admin.html

@@ -0,0 +1,6 @@
+{% extends "base.html" %}
+
+{% block content %}
+    <h1>Hi, {{ current_user.username }}!</h1>
+    Do you want to nuke the database?
+{% endblock %}

code/app/templates/base.html

@@ -7,8 +7,24 @@
       {% endif %}
     </head>
     <body>
-        <div>IGDB: <a href="/index">Home</a></div>
+      <div>IGDB:
+        <a href="{{ url_for('index') }}">Home</a>
+        {% if current_user.is_anonymous %}
+        <a href="{{ url_for('login') }}">Login</a>
+        {% else %}
+        <a href="{{ url_for('admin') }}">Administration</a>
+        <a href="{{ url_for('logout') }}">Logout</a>
+        {% endif %}
+      </div>
         <hr>
-        {% block content %}{% endblock %}
-    </body>
+        {% with messages = get_flashed_messages() %}
+        {% if messages %}
+        <ul>
+            {% for message in messages %}
+            <li>{{ message }}</li>
+            {% endfor %}
+        </ul>
+        {% endif %}
+        {% endwith %}
+        {% block content %}{% endblock %}    </body>
 </html>

code/app/templates/index.html

@@ -1,8 +1,6 @@
 {% extends "base.html" %}
 
 {% block content %}
-    <h1>Hi, {{ user.username }}!</h1>
-    {% for post in posts %}
-    <div><p>{{ post.author.username }} says: <b>{{ post.body }}</b></p></div>
-    {% endfor %}
+    <h1>IGDB: International Glacier Database</h1>
+    The IGDB is a database, that uses data from the <a href="https://dx.doi.org/10.5904/wgms-fog-2019-12">WGMS</a> to illustrate the consequences of climate change.
 {% endblock %}

code/app/templates/login.html

@@ -0,0 +1,24 @@
+{% extends "base.html" %}
+
+{% block content %}
+    <h1>Sign In</h1>
+    <form action="" method="post" novalidate>
+        {{ form.hidden_tag() }}
+        <p>
+            {{ form.username.label }}<br>
+            {{ form.username(size=32) }}<br>
+            {% for error in form.username.errors %}
+            <span style="color: red;">[{{ error }}]</span>
+            {% endfor %}
+        </p>
+        <p>
+            {{ form.password.label }}<br>
+            {{ form.password(size=32) }}<br>
+            {% for error in form.password.errors %}
+            <span style="color: red;">[{{ error }}]</span>
+            {% endfor %}
+        </p>
+        <p>{{ form.remember_me() }} {{ form.remember_me.label }}</p>
+        <p>{{ form.submit() }}</p>
+    </form>
+{% endblock %}