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,
Related
Lets say I have 2 radio buttons in my html script, of which one is checked by default:
<form action="" method="post">
<div class="radio-option checked">
<input type="radio" name="radioName" value="val_1"/>
</div>
<div class="radio-option">
<input type="radio" name="radioName" value="val_2"/>
</div>
<div>
<input type="submit" value="Confirm and continue"/>
</div>
</form>
If I click the submit button without clicking the other radio button, I get an error:
Bad Request The browser (or proxy) sent a request that this server
could not understand.
This happens because there is no value which is being transfered if a radio button is checked by default but not being selected with the mouse afterwards! This is what request.form shows me ImmutableMultiDict([]). If I select the other radio button with the mouse and click the submit button it shows me values ImmutableMultiDict(['radioName', 'val_2'])
I tried to catch the error like this, but it didn't work out:
if request.form == '':
flash('error')
return render_template('default_template.html')
How can I handle this within flask?
How can I set a default value, which can be sent to the server?
You could perform a check within flask. Check if request.form has items or if its empty and throw the error in that case.
A simple way of knowing if its empty would be, for example:
if len(request.form) == 0:
print('Error: The form is empty')
else:
print('The form has data, we can proceed')
Another way is:
if 'radioName' not in request.form:
print('Error: The form is empty')
...
But maybe flask has a better way of doing this or there are better practices to follow in these cases.
On the other hand, in the html snippet that you posted, none of the inputs is checked by default.
You have the checked css class on a div but not the checked attribute in an input with type=radio.
The correct use of checked attribute would be as follows:
<form action="" method="post">
<div class="radio-option checked">
<input type="radio" name="radioName" value="val_1" checked/>
</div>
<div class="radio-option">
<input type="radio" name="radioName" value="val_2"/>
</div>
<div>
<input type="submit" value="Confirm and continue"/>
</div>
</form>
This way, the radio input with value val_1, will be checked by default, populating the dictionary that goes to the server.
For more information, check out: https://developer.mozilla.org/en-US/docs/Web/HTML/Element/input/radio
You can also avoid sending empty forms to the server using the required attribute to make sure that the user fills the form as expected.
To learn more about this: https://developer.mozilla.org/en-US/docs/Learn/HTML/Forms/Form_validation
I hope it helps!
So I'm writing a web crawler to batch download PDFs from my university's website, as I don't fancy downloading them one by one.
I've got most the code working, using the 'requests' module. The issue is, you have to be signed in to a university account to access the PDFs, so I've set up requests to use cookies to sign into my university account before downloading the PDFs, however the HTML form to sign in on the university page is rather peculiar.
I've abstracted the HTML which can be found here:
<form action="/login" method="post">
<fieldset>
<div>
<label for="username">Username:</label>
<input id="username" name="username" type="text" value="" />
<label for="password">Password:</label>
<input id="password" name="password" type="password" value=""/>
<input type="hidden" name="lt" value="" />
<input type="hidden" name="execution" value="*very_long_encrypted_code*" />
<input type="hidden" name="_eventId" value="submit" />
<input type="submit" name="submit" value="Login" />
</div>
</fieldset>
</form>
Firstly the action parameter in the form does not reference a PHP file which I don't understand. Is action="/login" referencing the page itself, or http://www.blahblah/login/login? (the HTML is taken from the page http://www.blahblah/login.
Secondly, what's with all the 'hidden' inputs? I'm not sure how this page is taking the given login data and passing it to a PHP script.
This has led to the failure of the requests sign on in my python script:
import requests
user = input("User: ")
passw = input("Password: ")
payload = {"username" : user, "password" : passw}
s = requests.Session()
s.post(loginURL, data = payload)
r = s.get(url)
I would have thought this would take the login data and sign me into the page, but r is just assigned the original logon page. I'm assuming it's to do with the strange PHP interation in the HTML. Any ideas what I need to change?
EDIT: Thought I'd also mention there is no javascript on the page at all. Purely HTML & CSS
What you are looking at is likely a CSRF token
The linked answer is very good, but a summary is, these tokens used to make sure that you can't send malicious requests to a site from another page in your web browser. In this case it is a bit silly, because logging in has no consequences. It was likely added automatically by the framework your university website uses.
You will have to extract this token from the login page before doing your login POST and then include it with your data.
The full steps would be the following:
Fetch the login page
extract the token with e.g. BeautifulSoup or requests-html
Send the login request:
payload = {"username" : user, "password" : passw, "execution": token}
I have a form that accepts image uploads:
<form name="upload" enctype="multipart/form-data" method="post" class="form-horizontal">
<div class="control-group">
<div class="span2">
<label for="image" class="control-label">Upload image:</label>
</div>
<div class="span10">
<input id="image" name="image" type="file" class="span7" accept="image/*"/>
</div>
</div>
<div class="form-group">
<div class="span2"></div>
<div class="span10">
<button class="btn btn-medium btn-primary" type="submit">Submit</button>
</div>
</div>
</form>
When I request.vars['image'], the following is returned:
FieldStorage('image', 'a.png', '\x89PNG\r\n\x1a\n\x00...')
How do I access these items? If I attempt to work with it as I would a dict, I receive an error that the object is not indexable. I've never worked with FieldStorage before, so I'm not exactly sure what I need to do to access this data.
If anyone else is interested, this worked:
request.vars['image'].filename
request.vars['image'].value
For the file name and binary data, respectively. Just needed a quick summary of the available attributes: http://python.about.com/od/cgiformswithpython/ss/pycgitut1_3.htm
This is extremely helpful if you are trying to check some aspects of a file before trying to process a form. I wanted to get the sha256 hash of an uploaded file and make sure it hadn't been uploaded before. The upload is in a field Field('file', 'upload').
Originally, I used the following, but this consumes the data in request.vars.file so that, after successful processing, the file written to disk is empty.
file_contents = request.vars.file.read()
form.vars.file_hash = hashlib.sha256(file_contents).hexdigest()
form.vars.file_length = len(file_contents)
However, in the updated code below datasci's answer allows you to access the data without consuming it from request.vars.file. Might be obvious, but it took a long time for me to figure out what was going on!
# Is there a file - the value will be None when the page first loads and
# can be 'str' if submit is pressed without a file selected.
if request.vars.file != None and not isinstance(request.vars.file, str):
form.vars.file_name = request.vars.file.filename
form.vars.file_hash = hashlib.sha256(request.vars.file.value).hexdigest()
form.vars.file_size= len(request.vars.file.value)
if form.process(onvalidation=validate_dataset_upload).accepted:
# notify upload has worked
response.flash = ('Upload successful. A validation check will be run and '
'you will get an email with the results when it finishes.')
All of this means that the validate_dataset_upload function can now check form.vars.file_hash does not already exist in the underlying table.
I'm trying to get to grips with web2py/python. I want to get the user to fill in a search form, the term they search for is sent to my python script which should send the query to the blekko API and output the results to them in a new HTML page. I've implemented the following code but instead of my normal index page appearing, I'm getting the html response directly from blekko with '%(query)' /html appearing in it's search bar. Really need some help with this!
HTML form on the default/index.html page
<body>
<div id="MainArea">
<p align="center">MY SEARCH ENGINE</p>
<form name="form1" method="get" action="">
<label for="SearchBar"></label>
<div align="center">
<input name="SearchBar" type="text" id="SearchBar" value="" size = "100px"><br />
<input name="submit" type="submit" value="Search">
</div>
</form>
<p align="center"> </p>
Python code on the default.py controller
import urllib2
def index():
import urllib2
address = "http://www.blekko.com/?q='%(query)'+/html&auth=<mykey>"
query = request.vars.query
response = urllib2.urlopen(address)
html=response.read()
return html
I think you are misunderstanding how string formatting works. You need to put the address and query together still:
address = "http://www.blekko.com/?q='%(query)s'+/html&auth=<mykey>" % dict(query=request.vars.query)
Add a hidden field to your form, call it "submitted". Then reformat your controller function as such:
import urllib2
def index():
if request.vars.submitted:
address = "http://www.blekko.com/?q='%(query)'+/html&auth=<mykey>"
query = request.vars.query
response = urllib2.urlopen(address)
html=response.read()
return html
else:
return dict()
This will show your index page unless the form was submitted and the page received the "submitted" form variable.
The /html doesn't do anything. Glad your question got answered. There is python client code for the blekko search api here: https://github.com/sampsyo/python-blekko
I need to allow users to upload content directly to Amazon S3. This form works:
<form action="https://me.s3.amazonaws.com/" method="post" enctype='multipart/form-data' class="upload-form">{% csrf_token %}
<input type="hidden" name="key" value="videos/test.jpg">
<input type="hidden" name="AWSAccessKeyId" value="<access_key>">
<input type="hidden" name="acl" value="public-read">
<input type="hidden" name="policy" value="{{policy}}">
<input type="hidden" name="signature" value="{{signature}}">
<input type="hidden" name="Content-Type" value="image/jpeg">
<input type="submit" value="Upload" name="upload">
</form>
And in the function, I define policy and signature. However, I need to pass two variables to the form -- Content-Type and Key, which will only be known when the user presses the upload button. Thus, I need to pass these two variables to the template after the POST request but before the re-direction to Amazon.
It was suggested that I use urllib to do this. I have tried doing so the following way, but I keep getting an inscrutable HTTPError. This is what I currently have:
if request.method == 'POST':
# define the variables
urllib2.urlopen("https://me.amazonaws.com/",
urllib.urlencode([('key','videos/test3.jpg'),
('AWSAccessKeyId','<access_key'),
('acl','public-read'),
('policy',policy),
('signature',signature),
('Content-Type',content_type),
('file',file)]))
I have also tried hardcoding all the values instead of using variables but still get the same error. What am I doing incorrectly and what do I need to change to be able to redirect the form to Amazon, so the content can be uploaded directly to Amazon?
I recommend watching the form do its work with Firebug, enabled and set to the Net tab.
After completing the POST, click its [+] icon to expand, study the Headers, POST, Response tabs to see what you are missing and/or doing wrong.
Next separate this script from Django and put into a standalone file. Add one thing at a time to it and retest until it works. The lines below should increase visibility into your script.
import httplib
httplib.HTTPConnection.debuglevel = 1
I tried poking around with urllib myself, but as I don't have an account on AWS I didn't get farther than getting a 400 Bad Request response. Seems like a good sign, probably I just need valid host and key params etc.