I have just started to learn flask but I am stuck with this 405 error
# Weather App using Flask
## imports
import main
from flask import Flask
from flask import render_template
from flask import request
app = Flask(__name__)
## initalisation
#app.route('/')
def main_page(methods=["GET", "POST"]):
if request.method == "POST":
city = request.form("city")
print(city)
return render_template("main.html")
if __name__ == "__main__":
app.run(debug=True)
the main.html is
{% extends "base.html" %}
{% block content %}
<form method="POST">
<p><input type="text" name="city"></p>
<p><input type="submit" value="Submit"></p>
</form>
{% endblock %}
the POST is in the methods argument, but I cannot pinpoint where the error is
thanks in advance
Instead of having the methods list in the view function's parameters, you should have it in the brackets that follow your decorator, like so:
#app.route('/',methods=["GET","POST"])
def main_page():
# your view function
This will allow this route to be accessed through both GET and POST requests.
Related
I'm trying to execute a def/python script from flask, when clicked on button... but can't seem to figure it out.
Here's my Python Code
from flask import Flask, redirect, url_for, render_template, request
import webbrowser
app = Flask(__name__)
#app.route("/")
def home():
return render_template("index.html")
def contact():
if "open" in request.form:
print("Test")
elif "close" in request.form:
print("Test 2")
return render_template('contact.html')
if __name__ == "__main__":
app.run(debug=True)
And here is my HTML Code
<html>
<head>
<title>Home page</title>
</head>
<body>
{% extends "base.html" %}
{% block title %}Home Page{% endblock %}
{% block content %}
<h1>Test</h1>
<input type="submit" name="open" value="Open">
<input type="submit" name="close" value="Close">
{% endblock %}
</body>
</html> ```
I don't know what is in {% block content %} but you need to have a form in order to call backend where you provide the url route that you want to call and the method you want to use (usually with forms it's POST). Also in the /contact endpoint you need to provide #app.route('/contact') and that it would accept POST request #app.route('/contact', methods=['POST']). Modify your python and HTML to look like this:
from flask import Flask, redirect, url_for, render_template, request, jsonify
import webbrowser
app = Flask(__name__)
#app.route("/")
def home():
return render_template("index.html")
#app.route('/contact', methods=['POST'])
def contact():
result = False
if "open" in request.form:
result = activate_lamp() # expecting True as a result of function
elif "close" in request.form:
result = deactivate_lamp()
return jsonify({'result': result}) # expecting True as a result of function
if __name__ == "__main__":
app.run(debug=True)
<html>
<head>
<title>Home page</title>
</head>
<body>
<h1>Test</h1>
<form action="{{ url_for('contact') }}" method="post">
<input type="submit" name="open" value="Open">
<input type="submit" name="close" value="Close">
</form>
</body>
</html>
The jsonify will return an object to the front end with default 200 response code. Then you can either do something with it or ignore it. The idea is that in the route you can call other functions, but you must return a valid HTTP response to the front-end, e.g. jsonify, or plain return '', 200 might be enough.
Problem transferring variables across views I tried using sessions and could not get the connection to work. Say I have two pages, a home and page2. I have a flask app that will take user input from the home and print out input on page2.
For example, if you start my app, you will see this as the home page:
This part works fine, I am able to enter a value.
What I want to happen next, is after you click submit, page2 is generated showing what was just entered:
Whatever string value was entered on home should show up in the highlighted portion.
I have the following app.py file:
from flask import Flask, render_template, request, session
app = Flask(__name__)
#app.route('/', methods=['GET', 'POST'])
def home():
stringval = ''
if request.method == 'POST' and 'stringval' in request.form:
stringval = request.form.get('stringval')
session["stringvalue_topass"] = stringval
return render_template('page2.html', stringval = stringval)
return render_template("home.html")
#app.route('/page2', methods=['GET', 'POST'])
def page2():
stringvalue_get = session.get('stringvalue_topass')
return render_template('page2.html', stringvalue_get = stringvalue_get)
if __name__ == '__main__':
app.run(debug=True)
The following home.html:
<!doctype html>
<h1>Enter Value </h1>
<div class="main">
<form class="pure-form" method="POST" action="/page2">
stringval:<br>
<input type="text" name="stringval"><br>
<button type="submit" class="pure-button pure-button-primary" value="Submit">Submit!</button>
</form>
</div>
</body>
And the following page2.html
<!doctype html>
<h1>You have selected </h1>
<div class="main">
{% if stringvalue_get %}
<pre>
{% print(stringvalue_get) %}
</pre>
{% endif %}
</div>
</body>
Okay, there are a few issues here. Firstly, the action attribute of your form in home.html is set to "/page2". This means that when the form is submitted, the POST request is going to the /page2 endpoint rather than to the /home endpoint, where you have written the code for handling the form submission. We can fix this by just deleting the action attribute, as this means the form will post to then endpoint that loaded it - in this case /home.
Secondly, Flask sessions cannot be used without setting a secret key to encrypt the session. This can be done by assigning a value to app.secret_key, like so:
app = Flask(__name__)
app.secret_key = b"my_secret_key"
Finally, instead of passing the string to the template like so: render_template('page2.html', stringval = stringval), (note also that this should be stringval_get = stringval), you can access the session object directly from templates already. So, in all, we can change your application code to:
app.py:
from flask import Flask, render_template, request, session
app = Flask(__name__)
app.secret_key = b"my_secret_key"
#app.route('/', methods=['GET', 'POST'])
def home():
if request.method == 'POST' and 'stringval' in request.form:
session["stringvalue_topass"] = request.form.get('stringval')
return render_template('page2.html')
return render_template("home.html")
#app.route('/page2', methods=['GET', 'POST'])
def page2():
return render_template('page2.html')
And your templates to:
home.html:
<!doctype html>
<h1>Enter Value </h1>
<div class="main">
<form class="pure-form" method="POST">
stringval:<br>
<input type="text" name="stringval"><br>
<button type="submit" class="pure-button pure-button-primary" value="Submit">Submit!</button>
</form>
</div>
</body>
page2.html:
<!doctype html>
<h1>You have selected </h1>
<div class="main">
{% if 'stringvalue_topass' in session %}
<pre>
{% print(session["stringvalue_topass"]) %}
</pre>
{% endif %}
</div>
</body>
I am learning Flask and I've incurred into a supposedly beginners error:
Method Not Allowed The method is not allowed for the requested URL.
The thing is that, even though I reduce the code into something really simple, I can't find it. As far as I can see, the POST method is correctly set up (I will use comments to explain it).
The files are:
flaskblog.py
from flask import Flask, render_template, url_for, flash, redirect, request
from forms import RegistrationForm
app = Flask(__name__)
app.config['SECRET_KEY'] = '5791628bb0b13ce0c676dfde280ba245'
#app.route("/")
#app.route('/home', methods=['GET', 'POST']) # As one can see, the POST method is written there.
def home():
form = RegistrationForm()
return render_template('home.html', title='Home', form=form)
if __name__ == '__main__':
app.run(debug=True)
home.html
{% extends "layout.html" %}
{% block content %}
<div class="content-section">
<form method="POST" action=""> # The POST method is written there as well.
{{ form.hidden_tag() }}
<fieldset class="form-group">
<legend class="border-bottom mb-4">Join Today</legend>
<div class="form-group">
{{ form.username.label(class="form-control-label") }}
{{ form.username(class="form-control form-control-lg") }}
</div>
</fieldset>
<div class="form-group">
{{ form.submit(class="btn btn-outline-info") }}
</div>
</form>
</div>
{% endblock content %}
forms.py
from flask_wtf import FlaskForm
from wtforms import StringField, PasswordField, SubmitField, BooleanField
from wtforms.validators import DataRequired, Length, Email, EqualTo
class RegistrationForm(FlaskForm):
username = StringField('Username', validators=[DataRequired(), Length(min=2, max=20)])
submit = SubmitField('Sign Up')
I get the error when I submit the form, any help would be greatly appreciated!
Thanks!
You're not distinguishing between GET and POST requests appropriately in your home route. Flask defaults the incoming request, from the client, as a GET request since your definitions are off. However, this is an issue because the incoming request is actually a POST request as we can see from your form:
<form method="POST" action=""> # The POST method is written there as well.
Perhaps you could try modifying your home route to handle both POST/GET requests approriately, something along the lines of:
#app.route("/")
#app.route('/home', methods=['GET', 'POST'])
def home():
form = RegistrationForm()
# POST request
if form.validate_on_submit():
return redirect(url_for(<route>)) #route to be rendered if form properly validates
# GET request
return render_template('home.html', title='Home', form=form)
Hopefully that helps!
Im having trouble getting anything from the shown HTML form
I always get "ValueError: View function did not return a response"
Can somebody help me out here please? I have tried every variation of request.get that I can find on the web. Also if I specify my form should use post it uses get anyway - anybody know why this is?
Im new to flask so forgive my ignorance!
Thanks in advance.
The python file (routes.py)
from flask import Flask, render_template, request
import os
app = Flask(__name__)
musicpath = os.listdir(r"C:\Users\Oscar\Music\iTunes\iTunes Media\Music")
lsize = str(len(musicpath))
looper = len(musicpath)
#app.route('/')
def home():
return render_template('home.html', lsize=20, looper=looper, musicpath=musicpath)
#app.route('/pop', methods=['POST', 'GET'])
def pop():
if request.method == "GET":
text = request.args.get('som')
return text
#Have tried every variation of request.get
#app.route('/about')
def about():
name = "Hello!"
return render_template('about.html', name=name)
if __name__ == '__main__':
app.run(debug=True)
The html file (home.html)
{% extends "layout.html" %}
{% block content %}
<div class="jumbo">
<h2>A Music app!<h2>
</div>
<div>
{% if lsize %}
<form action="/pop">
<select id="som" size="20">
{% for i in range(looper):%}
<option value="{{i}}">{{ musicpath[i] }}</option>
{% endfor %}
</select>
</form>
{% endif %}
</div>
Select,
{% endblock %}
You don't have a name attribute on your select element. That is the attribute that browsers use to send information in forms; without it no data will be sent.
Note also that your pop handler does not do anything if the method is POST, even though you explicitly say you accept that method.
Im having trouble getting anything from the shown HTML form
I always get "ValueError: View function did not return a response"
Can somebody help me out here please? I have tried every variation of request.get that I can find on the web. Also if I specify my form should use post it uses get anyway - anybody know why this is?
Im new to flask so forgive my ignorance!
Thanks in advance.
The python file (routes.py)
from flask import Flask, render_template, request
import os
app = Flask(__name__)
musicpath = os.listdir(r"C:\Users\Oscar\Music\iTunes\iTunes Media\Music")
lsize = str(len(musicpath))
looper = len(musicpath)
#app.route('/')
def home():
return render_template('home.html', lsize=20, looper=looper, musicpath=musicpath)
#app.route('/pop', methods=['POST', 'GET'])
def pop():
if request.method == "GET":
text = request.args.get('som')
return text
#Have tried every variation of request.get
#app.route('/about')
def about():
name = "Hello!"
return render_template('about.html', name=name)
if __name__ == '__main__':
app.run(debug=True)
The html file (home.html)
{% extends "layout.html" %}
{% block content %}
<div class="jumbo">
<h2>A Music app!<h2>
</div>
<div>
{% if lsize %}
<form action="/pop">
<select id="som" size="20">
{% for i in range(looper):%}
<option value="{{i}}">{{ musicpath[i] }}</option>
{% endfor %}
</select>
</form>
{% endif %}
</div>
Select,
{% endblock %}
The Problem is that your HTML form does not have a name.
request.args.get("som") needs an HTML form input with the name "som"
<select name="som" id="som" size="20">
Just change that line and add a name. The form is not interested in the id attribute.
You don't specified the method of the form, you have to do it! For example use this<form method="POST action"/pop">
Your form action is /pop. That means that if you submit the form it will do a POST request to the address /pop. Your code does only return a value for a GET request, therefore Flask complains you do not return anything. Write some code to process a POST request and return a text or rendered template.
BTW, in the code for GET you refer to request.args.get('som'); this gives you request arguments (i.e. in the URL), not from the form. som is in the form, so you cannot refer to it this way.