I have been working on FlaskFM but am now having issues getting my representation for my Item class to show up the way I want it to. I’d like for under “Your current playlist” the actual song name to show up. Since the Item class doesn’t include this as per the instructions, I tried adding this into my database by adding a foreign key. However, when I do this, it just renders as “None.” Has anyone gotten to get this to display properly?
routes.py:
from app import app, db
#the User model: each user has a username, and a playlist_id foreign key referring
#to the user's Playlist
class User(db.Model):
id = db.Column(db.Integer, primary_key = True)
username = db.Column(db.String(50), index = True, unique = True)
playlist_id = db.Column(db.Integer, db.ForeignKey('playlist.id'))
#representation method
def __repr__(self):
return "{}".format(self.username)
#create the Song model here + add a nice representation method
class Song(db.Model):
id = db.Column(db.Integer, primary_key = True)
title = db.Column(db.String(50), index = True, unique = True)
artist = db.Column(db.String(50), index = True, unique = True)
n = db.Column(db.Integer, index = False, unique = False)
#representation method
def __repr__(self):
return "{} by {}".format(self.title, self.artist)
#create the Item model here + add a nice representation method
class Item(db.Model):
id = db.Column(db.Integer, primary_key = True)
song_id = db.Column(db.Integer, db.ForeignKey('song.id'))
playlist_id = db.Column(db.Integer, db.ForeignKey('playlist.id'))
title_two = db.Column(db.String(50), db.ForeignKey('song.title'))
#create the Playlist model here + add a nice representation method
def __repr__(self):
return "{}".format(self.title_two)
class Playlist(db.Model):
id = db.Column(db.Integer, primary_key = True)
items = db.relationship('Item', backref='playlist', lazy='dynamic')
app,py:
from flask import Flask, render_template
from flask_sqlalchemy import SQLAlchemy
#import SQLALchemy
app = Flask(__name__)
#set the SQLALCHEMY_DATABASE_URI key
app.config['SQLALCHEMY_DATABASE_URI'] = 'sqlite:///song_library.db'
app.config['SQLALCHEMY_TRACK_MODIFICATIONS'] = False
app.config['SECRET_KEY'] = 'you-will-never-guess'
#create an SQLAlchemy object named `db` and bind it to your app
db = SQLAlchemy(app)
#a simple initial greeting
@app.route('/')
@app.route('/index')
def greeting():
return render_template('greeting.html')
# app name
@app.errorhandler(404)
def not_found(e):
return render_template("404.html")
#uncomment the code below here when you are done creating database instance db and models
import routes
from models.py:
from flask import Flask
from flask_wtf import FlaskForm
from wtforms import StringField, SubmitField
from wtforms.validators import DataRequired
from app import app, db
from models import User, Song, Playlist, Item
from flask import render_template, request, url_for, redirect, flash
#A form for inputing new songs via Dashboard
class SongForm(FlaskForm):
title = StringField(label = "Song Title:", validators=[DataRequired()])
artist = StringField(label = "Artist:", validators=[DataRequired()])
submit = SubmitField("Add Song")
#A function we made to check if an item to be added is already in the playlist
def exists(item, playlist):
"""Return a boolean
True if playlist contains item. False otherwise.
"""
for i in playlist: #for each item in playlist
if i.song_id == item.song_id: #check if the primary key is equal
return True
return False
#The home page of FlaskFM
#Lists all the users currently in the database
#renders the home.html template providing the list of current users
@app.route('/profiles')
def profiles():
current_users = User.query.all() #change here to a database query
return render_template('users.html', current_users = current_users)
#Displays profile pages for a user with the user_id primary key
#renders the profile.html template for a specific user, song library and
#the user's playlist
@app.route('/profile/<int:user_id>')
def profile(user_id):
user = User.query.filter_by(id = user_id).first_or_404(description = "No such user found.")
songs = Song.query.all()
which_user = User.query.get(user_id)
my_playlist = Playlist.query.get(which_user.playlist_id) #change here to a database query
return render_template('profile.html', user = user, songs = songs, my_playlist = my_playlist)
#Adds new songs to a user's playlist from the song library
#redirects back to the profile that issued the addition
@app.route('/add_item/<int:user_id>/<int:song_id>/<int:playlist_id>')
def add_item(user_id, song_id, playlist_id):
new_item = Item(song_id = song_id, playlist_id = playlist_id)
user = User.query.filter_by(id = user_id).first_or_404(description = "No such user found.")
my_playlist = Playlist.query.filter_by(id = user.playlist_id).first()
if not exists(new_item, my_playlist.items):
song = Song.query.get(song_id)
#using db session add the new item
db.session.add(new_item)
song.n = song.n + 1
db.session.commit()
#increase the counter for the song associated with the new item
#commit the database changes here
return redirect(url_for('profile', user_id = user_id))
#Remove an item from a user's playlist
#Redirects back to the profile that issues the removal
@app.route('/remove_item/<int:user_id>/<int:item_id>')
def remove_item(user_id, item_id):
object_to_remove = Item.query.get(item_id)
db.session.delete(object_to_remove)
db.session.commit()
#from the Item model, fetch the item with primary key item_id to be deleted
#using db.session delete the item
#commit the deletion
return redirect(url_for('profile', user_id = user_id))
#Display the Dashboard page with a form for adding songs
#Renders the dashboard template
@app.route('/dashboard', methods=["GET", "POST"])
def dashboard():
form = SongForm()
if request.method == 'POST' and form.validate():
new_song = Song(title = form.title.data, artist = form.artist.data, n = 1)
#create a new song here
#add it to the database
#commit to the database
else:
flash(form.errors)
unpopular_songs = [] #add the ordering query here
songs = Song.query.all()
return render_template('dashboard.html', songs = songs, unpopular_songs = unpopular_songs, form = form)