We Keep Coding

Flask form data empty [duplicate]

This question already has answers here:
Sending data from HTML form to a Python script in Flask
(2 answers)
Closed 1 year ago.
I've created a form with flask. This is the python code that handles the requests that come from this form:
#app.route("/submitclips/", methods=['GET', 'POST'])
def submitclips():
print(request)
print(request.method)
result = request.form.to_dict(flat=False)
print(result)
print(request.data)
HTML code:
<form action="/submitclips" method="POST">
<input type="hidden" name="taskpath" value="paththotask">
<table>
<th>Video</th>
<th>Mute</th>
<th>Delete</th>
<th>Keep</th>
<tr>
<td>
<video width="320" height="240" controls>
<source src="videosource.mp4" type="video/mp4">
</video>
</td>
<td>
<input type="radio" id="name$mute" name="name" value="mute">
</td>
<td>
<input type="radio" id="name$delete" name="name" value="delete">
</td>
<td>
<input type="radio" id="name$keep" name="name" value="keep" checked>
</td>
</tr>
</table>
<input type="submit">
</form>
This is a table and has more than one row, I changed the values to make it more readable. I guarantee that all names are unique where they are supposed to be unique though.
It has some code below it, but it crashes there because the form seems to be empty. I have checked the HTML and it's all correct, all inputs have a name. I also recorded the network traffic on google chrome to test this and I can see that all data in the form is present in the request data. So I'm pretty sure it's correct on the front-end. The problem is that it just doesn't show up in this method. In the code you can see several print statements and all of these show me empty data and not the data that I could see in my chrome browser. The method is GET, I don't know if it should be GET. In HTML I selected it to be a POST method, but if I remove the GET option from the python code, it gives me a "method not allowed" error.
I don't know what to do, this is some older code that used to work on my windows machine. I didn't change anything about it, but now I'm working on linux and it's completely broken, none of the forms work, it's all empty data.

Here you have mentioned that the endpoint /submitclips has methods GET and POST. It means that whenever i hit the url "baseurl/submitclips" then this function will be executed. Inside the function you have not specified for which method you will have what response, i.e if i call the endpoint using GET or POST you will process it the same way. This is not a good practice. I suggest you put something like :
if request.method == 'POST' or if request.method == 'GET' to separate the execution based on the type of method.
Now coming to the HTML, you must have the HTML from where you are sending the request to the server. If that data is coming from a form, then as part of the form you can add two attributes,
<form method="post"> and <form action="/submitclips"> to specify that on submit of this form,you will be sending the form data through POST method to the "/submitclips" url. It will look like this.
<form method="post" action="/submitclips"">
For the Server side,
def submitclips():
if request.method == 'POST' :
print(request)
print(request.method)
result = request.form.to_dict(flat=False)
print(result)
print(request.data)
It should work after that.

I have found the error. My HTML code would submit the form to "/submitclips" while the python code received requests from "/submitclips/". I don't know why this is wrong though, the tutorial that I followed for flask told me specifically that putting a slash at the end meant that it could receive requests from both "/submitclips" and "/submitclips/". This also worked earlier on my windows machine, but doesn't work anymore on my linux machine. I'm glad it's solved, but if anyone has an explanation for why this is wrong, feel free to answer.

Grabbing the value of a HTML form input field?

There's a web page similar to: www.example.com/form.php
I want to use Python to grab one of the values from the HTML form on the page. For example, if the form had I could get the value "test" returned
I have googled this extensively but most relate to posting form data, or have advice to use Django or cgi-bin. I don't have access to the server directly so I can't do that.
I thought the library REQUESTS could do it but I can't see it in the documentation.
HTML:
<html>
<body>
<form method="" action="formpost.php" name="form1" id="form1">
<input type="text" name"field1" value="this is field1">
<input type="hidden" name="key" value="secret key field">
</form>
</body>
As an example, I'd like something like this in Python:
import special_library
html = special_library.get("http://www.example.com/form.php")
print html.get_field("wanted")
Has anyone got any suggestions to achieve this? Or any libraries I may not have thought of or been aware of?

You can use requests library, and lxml
Try this:
import requests
from lxml import html
s = requests.Session()
resp = s.get("http://www.example.com/form.php")
doc = html.fromstring(resp.text)
wanted_value = doc.xpath("//input[#class='wanted_class_name']/#value")
print(wanted_value)
You can check following resources:
requests
xpath

Django/Python: Pulling value from template into views.py

I currently have a search function in my views.py file like so:
def json_search(request):
query = request.GET.get('query')
api_key = locu_api
url = 'https://api.locu.com/v1_0/venue/search/?api_key=' + api_key
locality = query.replace(' ', '%20')
category =
final_url = url + "&locality=" + locality + "&category=" + category
json_obj = urllib2.urlopen(final_url)
decoded_data = json.load(json_obj)
return render(request, 'loc_search.html',
{'objects': decoded_data['objects']})
What I have set up is a drop-down search bar whereby I want the category variable within my json_search() function to automatically be assigned to the selected option on the drop-down bar before the form is submitted using the submit button. The search bar looks like this :
And the code like this:
<form action="{% url 'search' %}">
<div class="input-group">
<input name="query" input id="address" type="textbox" placeholder="City or Zipcode" class="form-control datebox">
<div class="input-group-btn">
<button class="btn btn-default" type="submit" id="addressSearch">Search</button>
<button name = "category_query" tabindex="-3" data-toggle="dropdown" class="btn btn-default dropdown-toggle" type="button">
<span class="caret"></span>
<span class="sr-only">Toggle Dropdown</span>
</button>
<ul class="dropdown-menu" >
<li>Resturant</li>
<li>Activities</li>
<li>Bar / Club</li>
<li class="divider"></li>
<li>other</li>
</ul>
</div>
</div>
</form>
Is this even possible?

You would have to get the value back to the backend view code in some fashion in order for that to happen.
It would be possible to do so prior submitting the form. For example, you could use an Ajax call within the template code to hit the same URL serviced by the json_search function, passing category in the URL, and then pulling it out of request.GET.
If you wanted it to be assigned upon dropdown selection, you would want to attach a click event handler via jQuery to that dropdown, and then in that handler's function, get the selected value, and then add it to the Ajax call back to your json_search function.
In your json_search code, you'll want to differentiate handling the submit (which should be a POST) vs. general GET handling (perhaps based on whether various parameters are present in the URL).
Edit in response to comment from OP:
It's certainly not trivial, especially if you've not worked with Ajax before, but it shouldn't be too bad overall (and once you get the hang of it, this paradigm can be used for all sorts of interaction with other modules like Datatables and many others, not to mention your own Django backend).
While there are many different ways to do this, I'm a fan of using jQuery's when in conjunction with done (used in examples on the same page). The when lets you fire off multiple asynchronous Ajax requests, and the done acts as a join point where you wait for them to finish before proceeding.

Yes, this is possible, you would make all the links in the dropdown have a onclick handler which would need to save the category. Then instead of a url for the form you would use a submit function which would send your form data + the category.
That is something easy to do with angular + ui.bootstrap.
with jQuery
http://plnkr.co/edit/iBY2n9dq8Tn95IUGwNAB?p=preview
You need to transform your links not to have a valid href and instead call a function, e.g.:
Restaurant
and add a hidden field for the category
<input name="category" input="" id="category" type="hidden" placeholder="Category" class="form-control" />
and some easy javascript
function setCategory(category) {
alert('category (hidden) = ' + category);
$('#category').val(category);
}

Sending data to server flask html

I am trying to create a simple checkbox that sends the data to server here is my html code.
<form action="." method="POST">
<div class="checksheet">
<input id="XML Parser" class="checkbox" type="checkbox"/>XML Parser
<input id="Feed Parser" class="checkbox" type="checkbox"/>Feed Parser
<input id="Text Parser" class="checkbox" type="checkbox"/>Text Parser
<input id="Case Normalization" class="checkbox" type="checkbox"/>Case Normalization
<input id="Stemmer" class="checkbox" type="checkbox"/> Stemmer
</div>
<div class="submit"><input type="submit" value="Send" name="raw_text"></div>
</form>
What I am trying to do is very similar to the question asked here: Send Data from a textbox into Flask?
But except with the text box.. I have checkboxes.
But I get this error:
Not Found
The requested URL was not found on the server.
If you entered the URL manually please check your spelling and try again.
MY server side code (in flask) is:
#app.route('/raw_text.html')
def home ():
file = "sample.xml"
contents = open(file).read()
contents = contents.decode('utf-8')
return render_template('raw_text.html', contents=contents,file=file)
#app.route('/raw_text.html',methods=['POST'])
def get_data():
print "REQUEST ",request.form()
data = request.form['raw_text']
print data
return "Processed"
Any suggestions.
Thanks

A few things:
Your checkbox elements need a name attribute, this is what is used when the data is sent to the back end. Each checkbox that is related to each other needs to have the same name.
Your action attribute needs to point to a URL. If you are posting it to the same page as the form, you can remove the attribute.
ID's cannot contain spaces.
To be accessible the check boxes need <label>s,

Submitting a form in mechanize

I'm having issues submitting the result of a form submission (I can submit a form, but I can't submit the form on the page that follows the first).
I have:
browser = mechanize.Browser()
browser.set_handle_robots(False)
browser.open('https://www.example.com/login')
browser.select_form(nr=0)
browser.form['j_username'] = 'username'
browser.form['j_password'] = 'password'
req = browser.submit()
This works, as print req results in
`
<body onload="document.forms[0].submit()">
<noscript>
<p>
<strong>Note:</strong> Since your browser does not support JavaScript,
you must press the Continue button once to proceed.
</p>
</noscript>
<form action="https://www.example.com/Shibboleth.sso/SAML2/POST" method="post">
<div>
<input type="hidden" name="RelayState" value="cookie:95ca495c"/>
<input type="hidden" name="SAMLResponse" value="really long encoded value"/>
</div>
<noscript>
<div>
<input type="submit" value="Continue"/>
</div>
</noscript>
</form>
</body>
`
But I get errors when I try to use req.select_form(nr=0)
I assume this is probably from something along the lines of how mechanize returns objects from submit() and that I'm going about this the wrong way.
Any input or guidance would be appreciated :)

try again browser.select_form(nr=0) instead of req.select_form(nr=0). (after submitting or clicking a link or so, the new response is considered as an actual browser page - like in a browser :) )