application.py

# from models_orm import *
from sqlalchemy import create_engine
from sqlalchemy.orm import scoped_session, sessionmaker
from flask import Flask, render_template, request,jsonify,session
from flask_session import Session
import requests


app=Flask(__name__)
# app.config["SQLALCHEMY_DATABASE_URI"]='postgres://mfnkrcrnelvvuw:59d18586b37964ae48eae31dff37910036faeca7b91bc0946390383ce1f56d82@ec2-54-145-249-177.compute-1.amazonaws.com:5432/dcmdr8nduf9duf'
# app.config["SQLALCHEMY_TRACK_MODIFICATIONS"]=False
app.config["SESSION_PERMANENT"]=False
app.config["SESSION_TYPE"]="filesystem"
Session(app)

engine= create_engine('postgres://mfnkrcrnelvvuw:59d18586b37964ae48eae31dff37910036faeca7b91bc0946390383ce1f56d82@ec2-54-145-249-177.compute-1.amazonaws.com:5432/dcmdr8nduf9duf')
db = scoped_session(sessionmaker(bind=engine))


# db.init_app(app) ##tigh database to flask

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

@app.route("/register")
def register():
    return render_template("registration.html")

@app.route("/books", methods=["POST","GET"])
def book_search():
    if request.method=="POST":
        username=request.form.get("username_login")
        password=request.form.get("password_login")
        ##only for testing error page. you should comment the next lines after you finish your task.
        if username=="" or password=="":
            return render_template("error.html", message="Your password or username field is empty. please, return again and correct your faults.", type_error="login")
        ###########################
        ##check if it exists in database or not
        out_id=db.execute("select id from users where username=:username and password=:password",{"username":username,"password":password})
        if out_id.rowcount==0:  ## username or password is not exist in database
            return render_template("error.html", message="Your password or username is not correct or may be you don't have an account. please, return back and correct your faults.", type_error="login")
        ##if valid render the book search page
        if(not("user_id" in session)):
            session["user_id"]=[]
            print("add new data to session")
        new_id=out_id.fetchone()[0]
        # print("session['user_id']=",session["user_id"])

        if ((len(session["user_id"])>0 and new_id!=session["user_id"][-1]) or (len(session["user_id"])==0)):
            session["user_id"].append(new_id)
        print(f"session now ={session['user_id']}")
        db.commit()
    return render_template("book_search_page.html",search_flag=0,books_list=[])


@app.route("/books/search", methods=["POST","GET"])
def after_searching():
    if request.method=="POST":
        search_name=request.form.get("search")
        filterType=request.form.get("filterType")
        print("search=", search_name)
        print("filterType=",filterType)
        if(filterType=="title"):
            out_result=db.execute("select * from books where title ILIKE :searchText", {"searchText":"%"+search_name+"%"})
        elif(filterType=="author"):
            out_result=db.execute("select * from books where author ILIKE :searchText", {"searchText":"%"+search_name+"%"})
        else:
            out_result=db.execute("select * from books where isbn ILIKE :searchText", {"searchText":"%"+search_name+"%"})
        out_data=out_result.fetchall()
        print("out_data=",out_data)
        db.commit()
    return render_template("book_search_page.html",search_flag=1, books_list=out_data)
    ###

@app.route("/books/search/<int:book_id>")
def book_details(book_id):
    if(not("book_id" in session)):
        session["book_id"]=[]
    session["book_id"].append(book_id)
    book_data=db.execute("select * from books where id=:book_id",{"book_id":book_id})
    print("book_data=",book_data)
    if(book_data.rowcount==0):
        return render_template("error.html", message="There is no information about this book currently.",\
                     type_error="book_search")
    book_item=book_data.fetchone()
    print("bookitem=",book_item)

    res = requests.get("https://www.googleapis.com/books/v1/volumes", params={"q": "isbn:"+book_item[1]})
    print(f"status code: {res.status_code}")
    if res.status_code !=200:
        average_rating="Null"
        rating_count="Null"
    else:
        json_api_data=res.json()
        if not("items" in json_api_data) or not("volumeInfo" in json_api_data["items"][0]):
            average_rating="Null"
            rating_count="Null"
        else:
            average_rating=json_api_data["items"][0]["volumeInfo"]["averageRating"] if ("averageRating" in json_api_data["items"][0]["volumeInfo"]) else "Null"
            rating_count=json_api_data["items"][0]["volumeInfo"]["ratingsCount"] if ("ratingsCount" in json_api_data["items"][0]["volumeInfo"]) else "Null"  
            print(f"average rating={average_rating} and ranting count={rating_count}")
    ##check reviews for the book-id and user-id
    review_data=db.execute("select users.username, reviews.rate, reviews.comment from reviews join users on reviews.user_id=users.id where book_id=:book_id",\
                    {"book_id":book_id})

    if review_data.rowcount==0:
        flag_review=0
        reviews=[]
    else:
        flag_review=1
        reviews=review_data.fetchall()

    db.commit()
    return render_template("book_details.html",book_item=book_item,average_rating=average_rating,\
        rating_count=rating_count,flag_review=flag_review,reviews=reviews)


@app.route("/books/search/submit-review", methods=["POST"])
def submit_book_review():
    rating=request.form.get("rating")
    comment=request.form.get("comment")
    if rating is None:
        return render_template("error.html", message="Please, rate your book. It is a mandatory field",\
                type_error="book_detail",book_id=session["book_id"][-1])

    review_data=db.execute("select * from reviews where book_id=:book_id and user_id=:user_id",\
            {"book_id":session["book_id"][-1], "user_id":session["user_id"][-1]})
    if review_data.rowcount>0:
        return render_template("error.html", message="You already submitted a review for this book. You can't submit another review for this book",\
                type_error="book_detail",book_id=session["book_id"][-1])
    
    db.execute("insert into reviews (rate, comment, user_id, book_id) values (:rate,:comment,:user_id,:book_id)",\
              {"rate":rating,"comment":comment,"user_id":session["user_id"][-1],"book_id":session["book_id"][-1]})

    db.commit()

    return render_template("success_submit.html",submit_type="review", book_id=session["book_id"][-1])



@app.route("/api/<string:isbn>")  
def request_json_api(isbn):
    isbn_data=db.execute("select * from books where isbn=:isbn",{"isbn":isbn})
    if(isbn_data.rowcount==0):
        # return render_template("error.html",message="404 Not found")
        return jsonify({"error":"not found", "message":"invalid ISBN"}),404
    book_item=isbn_data.fetchone()

    res = requests.get("https://www.googleapis.com/books/v1/volumes", params={"q": "isbn:"+isbn})
    print(f"status code: {res.status_code}")
    if (res.status_code !=200):
        average_rating="Null"
        rating_count="Null"
        published_date="Null" 
        isbn_10="Null"
        isbn_13="Null"
    else:
        json_api_data=res.json()
        if not("items" in json_api_data) or not("volumeInfo" in json_api_data["items"][0]):
            average_rating="Null"
            rating_count="Null"
            published_date="Null" 
            isbn_10="Null"
            isbn_13="Null"
        else:
            average_rating=json_api_data["items"][0]["volumeInfo"]["averageRating"] if ("averageRating" in json_api_data["items"][0]["volumeInfo"]) else "Null"
            rating_count=json_api_data["items"][0]["volumeInfo"]["ratingsCount"] if ("ratingsCount" in json_api_data["items"][0]["volumeInfo"]) else "Null"  
            published_date=json_api_data["items"][0]["volumeInfo"]["publishedDate"] if ("publishedDate" in json_api_data["items"][0]["volumeInfo"]) else "Null"
            isbn_10="Null"
            isbn_13="Null"
            if "industryIdentifiers" in json_api_data["items"][0]["volumeInfo"]:
                for isbn_dict in json_api_data["items"][0]["volumeInfo"]["industryIdentifiers"]:
                    if(isbn_dict["type"]=="ISBN_10"):
                        isbn_10=isbn_dict["identifier"]

                    if(isbn_dict["type"]=="ISBN_13"):
                        isbn_13=isbn_dict["identifier"]

    
    return jsonify({"title":book_item[2],\
                "author":book_item[3],\
                "publishedDate":published_date,\
                "ISBN_10":isbn_10,\
                "ISBN_13":isbn_13,\
                "reviewCount":rating_count,\
                "averageRating":average_rating \
                })




@app.route("/register/validity", methods=["POST"])
def check_registration():
    
    username=request.form.get("username_register")
    password=request.form.get("password_register")
    firstName=request.form.get("firstName")
    lastName=request.form.get("lastName")
    print(f"first name={firstName}")
    print(f"last name={lastName}")
    print(f"username={username}")
    print(f"password name={password}")
    if username=="" or password=="" or firstName=="" or lastName=="":
        return render_template("error.html", message="one or more fields of the registration is/are empty. please, return again and correct your faults.", type_error="registration")
    ##check if there  same username in database or not
    if db.execute("select * from users where username=:username",{"username":username}).rowcount>0:  ##this username exists in database
        return render_template("error.html", message="This username already exists in database. please, add a new username or return back to login page to sign in", type_error="registration")
    

    ##then add it to database if it doesn't exist
    db.execute("INSERT INTO users (username, password, firstName, lastName) values (:username, :password, :firstName, :lastName)",\
              {"username":username, "password":password, "firstName":firstName, "lastName":lastName})

    ##finally, return that the registration is submitted successfully.
    db.commit()
    return render_template("success_submit.html", submit_type="register")
    
# @app.route("/register/success")
# def success():
#     return render_template("success_submit.html")

if __name__== "__main__" :
    # with app.app_context(): ##to run this flask application
    #     main()
    app.run(debug=True)