Flask putting form into URL - python

I've been working on a form that sends data to a scraper and simultaneously generates a URL from form input. The returned templates works flawlessly, but the URL change ends up giving me the entire form in the URL and I can't figure out why.
The URL ends up looking like this:
http://localhost/options/%3Cinput%20id%3D%22symbol%22%20name%3D%22symbol%22%20type%3D%22text%22%20value%3D%22%22%3E
I'd like it to look like this:
http://localhost/options/ABC
Form class:
class OptionsForm(Form):
symbol = StringField('Enter a ticker symbol:', validators=[Required(), Length(min=1, max=5)])
submit = SubmitField('Get Options Quotes')
Views:
# Where the form data ends up
#app.route('/options/<symbol>', methods=['GET', 'POST'])
def options(symbol):
# Created this try/except so I could test functionality - for example, I can do 'localhost/options/ABC' and it works
try:
symbol = request.form['symbol']
except:
pass
return render_template('options.html', symbol=symbol, company_data=OS.pull_data(symbol, name=True))
# Where the form lives
#app.route('/', methods=['GET', 'POST'])
def index():
form = OptionsForm()
print(form.errors)
if form.validate_on_submit():
return redirect(url_for('options', symbol=form.symbol.data))
return render_template('index.html', options_form=form)
Template:
<div id="options_div">
<form method="POST" name="symbol_form" action="{{ url_for('options', symbol=options_form.symbol) }}">
{{ options_form.hidden_tag() }}
{{ options_form.symbol(size=10) }}
{{ options_form.submit(size=10) }}
</form>
Any help would be appreciated.

Try adding enctype='multipart/form-data' to the form tag. It looks like your form is using application/x-www-form-urlencoded, the default.
Edit OK so check this out. When your template is being rendered there is no value in that data attribute (In the url_for call). When not referencing the data attribute (as your original question shows), you're referencing the actual form element (which is why you see all of that html being passed in the url). Here are your options (that I see):
Use some kind of frontend javascript to bind the form's action attribute to the value in the input box. Something like angular would help for this (but is overkill if you don't use any of its other features).
Just have the form POST to /options (no symbol in url). Then, grab the symbol attribute from the form data.

Related

MultiFileField Doesn't Return Files, returns _str_

I'm trying to upload multiple images using WTForms in Flask using "MultiFileField, however, it returns a string instead of the file object.
So I tried using the below:
request.files.getlist(form.upload_field.data)
But it returns an empty list, so anyway I can handle this to save the photos to a directory
There is documentation of file uploads with Flask here, and you are going about it the right way through accessing the request.files object. I've come across two ways to get an empty list back from there:
1. enctype form html attribute not set
Here's an example template that renders the MultipleFileField():
template = """
<form action="" method="POST" enctype="multipart/form-data">
{{ form.upload_field() }}
{{ form.submit() }}
</form>
"""
If I remove the enctype=... part, the list of files returns empty, where it otherwise would have values. A page on the internet says:
This value is required when you are using forms that have a file upload control
2. Passing the wrong Key to request.files.getlist()
request.files is a werkzeug.MultiDict, which is a mapping of keys to values, designed to handle having multiple values for the same key.
Using the same form template as above, inspecting the keys of request.files (print(list(request.files.keys()))) upon POST reveals ['upload_field'].
werkzeug.MultiDict.getlist has a single required parameter:
key - The key to be looked up.
So the only key in the MultiDict instance at this point is the string 'upload_field', if we want to get anything back from the getlist method, this needs to be the key that we pass to getlist. In your example code, you pass the value of the form.upload_field.data attribute (which in my tests is None). Change that to 'upload_field' and you should be away.
Here's a working minimal example that will print the result of calling request.files.getlist() upon form submit. Run the script, visit http://127.0.0.1:5000 in your browser, upload a couple of files and watch the terminal output.
from flask import Flask, render_template_string, request
from wtforms import Form, MultipleFileField, SubmitField
app = Flask(__name__)
class MyForm(Form):
upload_field = MultipleFileField()
submit = SubmitField()
template = """
<form action="" method="POST" enctype="multipart/form-data">
{{ form.upload_field() }}
{{ form.submit() }}
</form>
"""
#app.route("/", methods=["GET", "POST"])
def route():
form = MyForm()
if request.method == "POST":
print(request.files.getlist("upload_field"))
return render_template_string(template, form=form)
if __name__ == "__main__":
app.run(debug=True)

When handling a form POST in a Django views.py, it appears to ignore the HttpResponse type

I have a Django application that generates a table of data. I have a form where you enter parameters and click one button to see the results or another to download a CSV. Seeing the results is working, but downloading the CSV is not.
I handle the response in the views.py, set the content type and disposition, and return the response. Rather than downloading the CSV, it displays the data as text. (I tried both StreamingHttpResponse and plain HttpResponse.) The same exact code works when handling a URL passing in the parameters. So, I tried a HttpResponseRedirect instead, and it does nothing. I even tried just redirecting to a plain URL, with no effect. I believe the response type is being ignored, but I don't know why.
html:
<form action="" method="post" class="form" id="form1">
{{ form.days }} {{ form.bgguserid }}
<input type="submit" value="Go!" id="button-blue"/>
<input type="submit" name="csv-button" value="CSV" id="csv-button"/>
</form>
views.py attempt 1:
def listgames(request, bgguserid, days=360):
if 'csv-button' in request.POST:
# create CSV in variable wb
response = StreamingHttpResponse(wb, content_type='text/csv')
response['Content-Disposition'] = 'attachment; filename="collectionvalue.csv"'
return response
attempt 2, the same but with:
response = HttpResponseRedirect ('/collection/{0}/csv/{1}/'.format(bgguserid,days))
I'm open to other solutions like a client-side redirect to the functioning URL, but I don't want to lose the form validation, and my HTML/javascript skills are weak.
I figured out the problem.
The code in views.py (which I partly copied from somewhere) was creating a new HttpRequest object from the return value of the form handling method.
def indexform(request):
if request.method == 'POST':
form = IndexForm(request.POST)
# Check if the form is valid:
if form.is_valid():
# process the data in form.cleaned_data as required
response = listgames(request, bgguserid=form.cleaned_data['bgguserid'], days=form.cleaned_data['days'])
# redirect to a new URL:
return HttpRequest(response)
By changing that last line to just return response, it works as intended. Sorry for wasting anyone's time.

I want something to be executed through django

I know this question was asked before, but none worked for me. I have this code that I want it to be executed when a button is clicked and a message is passed
import time
from sinchsms import SinchSMS
number = '+yourmobilenumber'
message = 'I love SMS!'
client = SinchSMS(your_app_key, your_app_secret)
print("Sending '%s' to %s" % (message, number))
response = client.send_message(number, message)
message_id = response['messageId']
response = client.check_status(message_id)
while response['status'] != 'Successful':
print(response['status'])
time.sleep(1)
response = client.check_status(message_id)
print(response['status'])
Basically, what I need is to add an input in a template "HTML File", this input get passed to the message variable in the code above, same with the number. I can easily do that with instances, but how can the below get executed when a button is clicked from the form in the template?
I'm kinda newbie in Django and still finding my way
Here is the tutorial that explains how to make the python file, but execute it from the shell, not a django application.
I hope I was clear describing my problem and any help would be appreciated!
All you need is a form with a message field. In a view, you want to show that form and when the user press submit, you want to execute your script.
Here is some pseudo-code:
urls.py
url('^my-page/' my_views.my_view, name='my-page'),
forms.py
SmsForm(forms.Form):
message = fields.CharField(...)
my_views.py
def my_view(request):
form = SmsForm(data=request.POST or None)
if request.method == 'POST':
if form.is_valid():
send_sms(form.cleaned_data['message']) # do this last
messages.success(request, "Success")
return HttpResponseRedirect(request.path)
else:
messages.warning(request, "Failure")
return render(request, 'my_template.html', {'form': form})
Check the Django documentation about urls, views, forms and messages and proceed step by step:
get the page to load
get the form to load
get the form submission to work and simply show "Success" or "Failure"
finally, write the send_sms function (you've almost done it)
Lets start from the dust cloud.
What you are asking is mostly about how the web pages work. You need to know how to pass parameters using HTML. There are lots of ways to do it. But with django there is a pattern.
You need a url, and a view to catch any requests. Then you need to create a template and a form inside it. With this form you could create some requests to send data to your view.
To create you need to edit urls.py inside your project add an url:
urls.py
from django.conf.urls import url
from my_app.views import my_view
urlpatterns = [
...
url(r'^my_url$', my_view, name='my_view')
...
]
For more about urls please look at URL dispatcher page at documentation.
Then create your view inside your app which is my_app in my example. Edit my_app/views.py
my_app/views.py
from django.http import HttpResponse
def my_view(request):
return HttpResponse('IT WORKS!')
This way you get a working view which could be accessed with path /my_url. If you run ./manage.py runserver you could access your view from http://localhost:8000/my_url.
To create a form you need to create a template. By default django searches app directories for templates. Create a templates directory in your app, in our case my_app/templates and create an HTML file inside. For example my_app/templates/my_form.html. But i advice to create one more directory inside templates directory. my_app/templates/my_app/my_form.html. This will prevent template conflicts. You can check Templates page at documentation for more.
my_app/templates/my_app/my_form.html
<html>
<body>
<form action="/my_url" method="POST">
{% csrf_token %}
<input type="text" name="number">
<input type="text" name="message">
<input type="submit" value="Run My Code">
</form>
</body>
</html>
This is the one of the ways of creating your form. But I do not recommend it. I will make it prettier. But first lets "Make it work", edit your views.py:
csrf_token is a django builtin template tag, to put CSRF token into your form. By default django requires CSRF tokens at every post
request.
my_app/views.py
from django.http import HttpResponse
from django.shortcuts import render
def my_view(request):
if request.method == 'GET':
return render('my_app/my_form.html')
elif request.method == 'POST':
# get post parameters or None as default value
number = request.POST.get('number', None)
message = request.POST.get('message', None)
# check if parameters are None or not
if number is None or message is None:
return HttpResponse('Number and Message should be passed')
# your code goes here
...
return HttpResponse('Your code result')
Till this point the purpose of this answer was "Making it work". Lets convert it nice and clean. First of all we would create Form. Forms are like models, which helps you create forms as objects. It also handles form validations. Forms are saved inside forms directory generally. Create my_app/forms.py and edit it:
my_app/forms.py
from django import forms
class MyForm(forms.Form):
number = forms.CharField(max_length=15, required=True)
message = forms.CharField(max_length=160, required=True)
Put your form inside your template:
my_app/templates/my_app/my_form.html
<html>
<body>
<form action="{% url 'my_view' %}" method="POST">
{% csrf_token %}
{{ form }}
</form>
</body>
</html>
Besides the form, the action of the HTML form tag is also changed.
url template tag is used to get url form url name specified in urls.py.
Instead of url tag, {{ request.path }} could have been used.
Create a form instance and pass it to the template rendering:
my_app/views.py
from django.http import HttpResponse
from django.shortcuts import render
from .forms import MyForm
def my_view(request):
if request.method == 'GET':
form = MyForm()
return render('my_app/my_form.html', {'form': form})
elif request.method == 'POST':
form = MyForm(request.POST)
# check if for is not valid
if not form.is_valid():
# return same template with the form
# form will show errors on it.
return render('my_app/my_form.html', {'form': form})
# your code goes here
...
return HttpResponse('Your code result')
You can use class based vies to write your view, but it's not necessary. I hope it helps.
You can create a view that takes up query parameters from the url and use it for further implementation. Then you can create a link/button in the html template which can redirect you to that url. For example:
in urls.py:
url(r'^run_a/(?P<msg>\w{0,25})/(?P<num>\w{0,25})/$', yourcode, name='get_msg'),
in template:
submit
in views.py:
def get_msg(request,msg,num):
message=msg
number=num
#rest of the code
Hope this helps :)

Using POST for flask url

I've been looking at other stack questions but I am still confused on a concept that I think is very simple to most people on here. Basically, I'm trying to understand how my data from my form will post to my url route when form.validate_on_submit. Apologies in advance for bad terminology with Get/Post
I have the following form using WTForms:
class Info(Form):
name = StringField('Name', validators=[Length(0, 64)],filters=[lambda x: x or None])
submit = SubmitField('Submit')
Then in my views.py I use the form.
#main.route('/people/', methods=('GET', 'POST'))
def person():
form = Info()
if form.validate_on_submit():
name = form.name.data
return redirect(url_for('.find_person', name=name))
return render_template('mytemplate.html', form=form)
I would want the url to post to something like #main.route/people/.
Then in find_person() I would be able to use request.form to get the arguments. Thanks in advance
In your HTML template, when setting up your form tags, make sure it looks like:
<form action="{{ url_for('people') }}" method="post">
<...content of your form here...>
</form>
I'm trying to understand how my data from my form will post to my url route when form.validate_on_submit
Your form data is implicitly fetched from flask.request.form during the construction of your Info object. From the doc for flask_wtf.Form.__init__: "If formdata is not specified, this will use flask.request.form. Explicitly pass formdata = None to prevent this."

What is the cause of the Bad Request Error when submitting form in Flask application?

After reading many similar sounding problems and the relevant Flask docs, I cannot seem to figure out what is generating the following error upon submitting a form:
400 Bad Request
The browser (or proxy) sent a request that this server could not understand.
While the form always displays properly, the bad request happens when I submit an HTML form that ties to either of these functions:
#app.route('/app/business', methods=['GET', 'POST'])
def apply_business():
if request.method == 'POST':
new_account = Business(name=request.form['name_field'], email=request.form['email_field'], account_type="business",
q1=request.form['q1_field'], q2=request.form['q2_field'], q3=request.form['q3_field'], q4=request.form['q4_field'],
q5=request.form['q5_field'], q6=request.form['q6_field'], q7=request.form['q7_field'],
account_status="pending", time=datetime.datetime.utcnow())
db.session.add(new_account)
db.session.commit()
session['name'] = request.form['name_field']
return redirect(url_for('success'))
return render_template('application.html', accounttype="business")
#app.route('/app/student', methods=['GET', 'POST'])
def apply_student():
if request.method == 'POST':
new_account = Student(name=request.form['name_field'], email=request.form['email_field'], account_type="student",
q1=request.form['q1_field'], q2=request.form['q2_field'], q3=request.form['q3_field'], q4=request.form['q4_field'],
q5=request.form['q5_field'], q6=request.form['q6_field'], q7=request.form['q7_field'], q8=request.form['q8_field'],
q9=request.form['q9_field'], q10=request.form['q10_field'],
account_status="pending", time=datetime.datetime.utcnow())
db.session.add(new_account)
db.session.commit()
session['name'] = request.form['name_field']
return redirect(url_for('success'))
return render_template('application.html', accounttype="student")
The relevant part of HTML is
<html>
<head>
<title>apply</title>
</head>
<body>
{% if accounttype=="business" %}
<form action="{{ url_for('apply_business') }}" method=post class="application_form">
{% elif accounttype=="student" %}
<form action="{{ url_for('apply_student') }}" method=post class="application_form">
{% endif %}
<p>Full Name:</p>
<input name="name_field" placeholder="First and Last">
<p>Email Address:</p>
<input name="email_field" placeholder="your#email.com">
...
The problem for most people was not calling GET or POST, but I am doing just that in both functions, and I double checked to make sure I imported everything necessary, such as from flask import request. I also queried the database and confirmed that the additions from the form weren't added.
In the Flask app, I was requesting form fields that were labeled slightly different in the HTML form. Keeping the names consistent is a must. More can be read at this question Form sending error, Flask
The solution was simple and uncovered in the comments. As addressed in this question, Form sending error, Flask, and pointed out by Sean Vieira,
...the issue is that Flask raises an HTTP error when it fails to find a
key in the args and form dictionaries. What Flask assumes by default
is that if you are asking for a particular key and it's not there then
something got left out of the request and the entire request is
invalid.
In other words, if only one form element that you request in Python cannot be found in HTML, then the POST request is not valid and the error appears, in my case without any irregularities in the traceback. For me, it was a lack of consistency with spelling: in the HTML, I labeled various form inputs
<input name="question1_field" placeholder="question one">
while in Python, when there was a POST called, I grab a nonexistent form with
request.form['question1']
whereas, to be consistent with my HTML form names, it needed to be
request.form['question1_field']

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