from flask import Flask, render_template, request, redirect
from werkzeug import secure_filename
app = Flask(__name__)


@app.route('/uploader', methods = ['GET','POST'])
def upload():
 new=nrecs[['UserID','ProductID','Rating']]
 new['Recommendations'] = list(zip(new.ProductID, new.Rating))
 res=new[['UserID','Recommendations']]
 res_new=res['Recommendations'].groupby([res.UserID]).apply(list).reset_index()
 pd.options.display.max_colwidth = 500
 return render_template('simple.html', tables=[res_new.to_html(classes='data')], titles='')

@app.route('/download-csv', methods = ['GET'])
def download():
return res_new.to_csv('Recommendations.csv')

from flask import Flask, render_template, send_file
app = Flask(__name__)

@app.route('/uploader', methods = ['GET','POST'])
def upload():
    new=nrecs[['UserID','ProductID','Rating']]
    new['Recommendations'] = list(zip(new.ProductID, new.Rating))
    res=new[['UserID','Recommendations']]
    res_new=res['Recommendations'].groupby([res.UserID]).apply(list).reset_index()

    # store the dataframe on the server.
    res_new.to_csv('Recommendations.csv')

    pd.options.display.max_colwidth = 500
    return render_template('simple.html', tables=[res_new.to_html(classes='data')], titles='')

@app.route('/download-csv', methods = ['GET'])
def download():

    # return the CSV file to the user here.
    return send_file('Recommendations.csv')

from flask import Flask, render_template, session
app = Flask(__name__)
# secret key is needed for session
app.secret_key = 'your secret key'

@app.route('/uploader', methods = ['GET','POST'])
def upload():
    new=nrecs[['UserID','ProductID','Rating']]
    new['Recommendations'] = list(zip(new.ProductID, new.Rating))
    res=new[['UserID','Recommendations']]
    res_new=res['Recommendations'].groupby([res.UserID]).apply(list).reset_index()

    session['reco_df'] = res_new

    pd.options.display.max_colwidth = 500
    return render_template('simple.html', tables=[res_new.to_html(classes='data')], titles='')

@app.route('/download-csv', methods = ['GET'])
def download():
    return session['reco_df'].to_csv('Recommendations.csv')