At this URL / or /login
If you do not have account then you can Signup (register)
Once you login, you will to redirected to home page which looks like
From home page, you can check the books available in the database.
On this page, you can search for your book of interest either using ISBN, author or title.
Once you click on the book, you will be taken to this page where you can see the book details and also review from Goodreads. Here you can also write your own review and give rating from 1-5.
You can only write review once and you can see it by going to that book's info.
Create PostegreSQL database and then create table (its in create_table.sql)
CREATE TABLE books ( id SERIAL PRIMARY KEY,
isbn TEXT NOT NULL,
title TEXT NOT NULL,
author TEXT NOT NULL,
year INTEGER NOT NULL
);
Import data into the books table using sqlalchemy (its in import.py). For sqlalchemy to work, you need to export DATABASE_URL using export DATABASE_URL="<actual_url>" as an environment variable or directly put into the python file as variable.
f = open("books.csv")
reader = csv.reader(f)
next(reader)
for isbn, title, author, year in reader:
db.execute("INSERT INTO books (isbn, title, author, year) VALUES (:isbn, :title, :author, :year)",
{"isbn": isbn, "title": title, "author": author, "year":year})
db.commit()
In the application.py, you can see that every app.route() followed by a function which will run under appropriate POST or GET request. For example at / URL
@app.route("/")
def index():
if 'user_id' in session:
user = db.execute('SELECT * FROM users WHERE id = :id',
{'id':session['user_id']}).fetchone()
if user:
return render_template('user_home.html', user = user)
else:
return render_template('login.html')
Once a user logs in, his id is appended into session dictionary
@app.route('/login', methods=["POST", 'GET'])
def login():
'''Login into to write reviews'''
# get username and password
if request.method == 'POST':
username = request.form.get('username')
password = request.form.get('password')
user = db.execute('SELECT * FROM users WHERE username = :username',{'username':username}).fetchone()
if user:
if user.password == password:
session['user_id'] = user.id
return render_template('user_home.html', user = user)
else:
return render_template('error.html', primary_message = 'Error :(',
message = 'Woops wrong password or username')
else:
return render_template('error.html', primary_message = 'Error :(',
message = "You have either put wrong username or password")
else:
if 'user_id' in session:
user = db.execute('SELECT * FROM users WHERE id = :id',
{'id':session['user_id']}).fetchone()
if user:
return render_template('user_home.html', user = user)
return render_template('login.html')
Now we can check from anywhere, whether a user has logged in or not. For example, in layout.html in templates folder which is the base html from which every other pages inherit from, uses this session dict.
<div class = 'sidenav'>
{% if 'user_id' in session %}
<a href="{{ url_for('logout') }}">Logout</a>
{% else %}
<a href="{{ url_for('login') }}">Login</a>
{% endif %}
<a href="{{ url_for('books')}}">Books</a>
</div>
For logging out, we have to simply remove this key from the dictionary
@app.route('/logout')
def logout():
'''Logging out or ending a session'''
session.pop('user_id', None)
return render_template('login.html')
If user does not have an account then he/she has to register and the data provided is inserted into the table. Here only post request method is allowed.
@app.route('/register', methods = ["POST"])
def register():
'''Register user'''
#get username
username = request.form.get('username')
password = request.form.get('password')
verify_password = request.form.get('verify_password')
if password != verify_password:
return render_template('error.html', primary_message = 'Error :(',
message = 'Password did not match')
elif db.execute('SELECT * FROM users WHERE username = :username', {'username':username}).rowcount != 0:
return render_template('error.html', primary_message = 'Error :(',
message = 'User ' + username + ' already exits')
else:
db.execute('INSERT INTO users (username, password) VALUES (:username, :password)',
{'username':username, 'password':password})
db.commit()
return render_template('error.html', primary_message = 'Succesfull :)',
message = 'Succesfully registered')
You can get the data in the following json format once you request at url: /api/<string:isbn>
jsonify({
'title':book.title,
'author':book.author,
'year':book.year,
'isbn':isbn,
'review_count':good_read[1],
'average_score':good_read[0]
}
And the following fucntion returns the data that is requested from the above url
@app.route('/api/<string:isbn>')
def book_api(isbn):
'''API that returns data in json format once requested'''
book = db.execute('SELECT * FROM books WHERE isbn = :isbn', {'isbn':isbn}).fetchone()
if book is None:
return jsonify({'error':'invalid ISBN'}), 404
good_read = goodread_data_getter(isbn)
return jsonify({
'title':book.title,
'author':book.author,
'year':book.year,
'isbn':isbn,
'review_count':good_read[1],
'average_score':good_read[0]
})
We are using api provided by Goodreads to get work_ratings_count and average_rating and the function that is getting this data is in application.py
# Function to get the data using api request
def goodread_data_getter(isbn):
res = requests.get("https://www.goodreads.com/book/review_counts.json",
params={"key": goodread_api_key, "isbns": isbn})
if res.status_code == 404:
return ['None', "None"]
else:
return [res.json()['books'][0]['average_rating'],
res.json()['books'][0]['work_ratings_count']]
You can search from the library using isbn, author or title. The following snippet extracts the query from POST request and then searches for it in the database using SELECT and LIKE
if( search_type or search) is None:
return render_template('books.html',books = books, status = True)
if search_type.lower() == 'isbn':
search_result = db.execute("SELECT * FROM books WHERE isbn LIKE :search",
{'search':'%' + search + '%'}).fetchall()
elif search_type.lower() == 'author':
search_result = db.execute("SELECT * FROM books WHERE author LIKE :search",
{'search':'%' + search + '%'}).fetchall()
else:
search_result = db.execute("SELECT * FROM books WHERE title LIKE :search",
{'search':'%' + search + '%'}).fetchall()