Code review and sanitation. More understanding of concepts

frontend/app.py

@@ -2,7 +2,10 @@ import pymongo
 from flask import Flask, request, render_template, url_for, redirect
 
 app = Flask(__name__)
-
+myclient = pymongo.MongoClient("mongodb://admin:pass@localhost:27017")
+mydb = myclient["groclist_db"]
+mycol_users = mydb["groclist_users"]
+username=""
 
 @app.route("/", methods=['GET', 'POST'])
 def groclist_home():
@@ -15,29 +18,28 @@ def groclist_home():
 
 	return render_template('index.html',error=error)
 
-@app.route("/welcome")
-def groclist_welcome():
-	return render_template("welcome.html")
-
 @app.route("/login", methods=['GET', 'POST'])
 def groclist_login():
 	error = None
 	if request.method == 'POST':
-		myclient = pymongo.MongoClient("mongodb://admin:pass@localhost:27017")
-		mydb = myclient["groclist_db"]
-		mycol = mydb["groclist_users"]
 		username = request.form['username']
 		password = request.form['password']
-		name = ""
-		if mycol.find_one({"username": username, "password": password}):
-			# for user_info in mycol.find({}, {"name": 0}):
-			#	print("Welkom", user_info)
+		if mycol_users.find_one({"username": username, "password": password}):
 			return redirect(url_for('groclist_welcome'))
 		else:
 			error = 'Username of wachtwoord onbekend. Probeer opnieuw'
 
 	return render_template("login.html", error=error)
 
+@app.route("/welcome", methods=['GET', 'POST'])
+def groclist_welcome():
+	if request.method == 'GET':
+		userid = mycol_users.find_one({"username": username}, {"_id": 1})
+		print(userid)
+		return render_template("welcome.html", userid=userid)
+	else:
+		error = "Userid is niet bekend. Database defect"
+		return render_template("index.html", error=error)
 
 app.add_url_rule("/welcome", "welcome", groclist_welcome)