This is my sample HTML file
<html>
<head>
<title>
</title>
</head>
<body>
<form action="">
Value a:<br>
<input type="text" name="Va">
<br>
Value b:<br>
<input type="text" name="Vb">
<br><br>
<input type="submit">
</form>
<textarea rows="4" cols="10">
</textarea>
<p>
</p>
</body>
</html>
And a given template Tornado server code:(I also need help on the explanation of each section of the following code)
import tornado.ioloop
import tornado.web
import tornado.httpserver
import tornado.gen
import tornado.options
tornado.options.parse_command_line()
class APIHandler(tornado.web.RequestHandler):
#tornado.web.asynchronous
def get(self):
self.render('template.html')
#tornado.gen.engine
def post(self):
try:
num = int(self.get_argument('num'))
except:
num = 5
self.render('template.html')
app = tornado.web.Application([(r"/next_rec",APIHandler),])
if __name__ == "__main__":
server = tornado.httpserver.HTTPServer(app)
server.bind(48763)
server.start(5)
tornado.ioloop.IOLoop.current().start()
and finally my python code:
if __name__ == '__main__':
a = int(raw_input())
b = int(raw_input())
print a+b
I am using a simple 'a+b' function to test out this feature. But my problem is I can't figure out a way to link them together. So my ultimate goal is to click on the "Submit" button on the HTML, pass on two values to the Tornado server, use it as input in my python script and finally show the output in the text area of the HTML or on another page. I'm know there are tons of information on the web, but I'm completely new to Tornado (near 0 knowledge) and most of them I can't really understand. Help on methods or keywords for search is much appreciated, thank you very much. (please keep answers as basic as possible, it will help a lot, thanks!)
First of all you should check the official documentation. It is quite simple and it targets the newcomers.
Also in this short guide, the sections of a similar code as your is being explained with simplicity.
Now for your code:
On your template you need to specify that the form should send a post request on submit by adding <form method="post" id="sum_form">
Also you need to make sure that you will be submit the data added in the form on an event: $("#sum_form").submit();
On your post method you need to read the passed numbers from your client's form, add them and then send them back to the template as a parameter.
For example:
def post(self):
numA = int(self.get_argument('Va'))
numB = int(self.get_argument('VB'))
sumAB = numA + numB
self.render('template.html',sumAB=sumAB)
In you template.html you need to add a field where you will display the passed sum as a jinja variable : {{sumAB}}
Related
I am trying to display a timer of 5minutes (for example). I am using flask.
I know it could be good to use javascript but I really want to do it with python.
I have two issues:
First issue: display of the timer - issue to overwrite
I wrote a function for the timer in python which is supposed to display (for example for 50 seconds):
00:50 then remove 00:50 and have00:49, and so on...
But it is displaying:
00:50
00:49
00:48
...
Here is my code: screen.py
from flask import Flask, Response, request, render_template, render_template_string, stream_with_context
import time
app = Flask(__name__)
timing=0
#app.route('/content', methods=['POST', 'GET']) # render the content a url differnt from index. This will be streamed into the iframe
def content():
global timing
timing = 10
# if request.form.get("submit"):
# timing = request.form['timing']
# print(timing)
def countdown(t):
while t:
mins, secs = divmod(t, 60)
timer = '{:02d}:{:02d}'.format(mins, secs)
print(timer, end="\r")
yield timer
time.sleep(1)
t -= 1
# return timer
return app.response_class(countdown(timing)) #at the moment the time value is hardcoded in the function just for simplicity
# return render_template('display.html')
#app.route('/')
def index():
value = "Bonjour"
title_html = value
return render_template('display.html', message=title_html) # render a template at the index. The content will be embedded in this template
if __name__ == '__main__':
app.run(use_reloader=False)
I would like to find the equivalence of print(timer, end="\r") for yield in order to overwrite the value of timer and not see all the results when it's decreasing. I hope my explanation is clear.
Second issue: Input value of the timer
As you can see in my code screen.py, my value for timing is hardcoded timing=10. But I would like to allow the user to enter the value he wants in input like that:
if request.form.get("submit"):
timing = request.form['timing']
print(timing)
You can see these lines in screen.py, I commented them to leave timing=10 because when I write these lines I obtain the following error:
Method Not Allowed
The method is not allowed for the requested URL.
127.0.0.1 - - [02/Aug/2021 12:50:26] "POST / HTTP/1.1" 405 -
Here is the HTML Code linked to my python code display.html:
<!DOCTYPE HTML>
<html>
<head>
<link rel="stylesheet" href='/static/main.css'/>
<title>your dish</title>
</head>
<body>
<h1>{{message}}! Here are some informations about your dish:</h1>
<h2> countdown </h2>
<!-- <p>{{message}}</p> -->
<form method="POST" action=".">
<p><input name="timing" value="{{timing}}" placeholder="Enter your time"></p>
<input type="submit" name="submit" value="submit">
</form>
<div>
<iframe frameborder="0" noresize="noresize"
style='background: transparent; width: 100%; height:100%;' src="{{ url_for('content')}}"></iframe>
</div>
</body>
</html>
How can I avoid this error and take into consideration the value entered by the user in the input field of my display.html?
I tryed to run your script locally but I am not sure where do you expect to see the timer; I assume you used the countdown func from here.
I would like to propose you a different approach: stream dynamically the counter to the web page using an iframe:
from flask import Flask, render_template, Response
import time
app = Flask(__name__)
#app.route('/content') # render the content a url differnt from index. This will be streamed into the iframe
def content():
def timer(t):
for i in range(t):
time.sleep(5) #put 60 here if you want to have seconds
yield str(i)
return Response(timer(10), mimetype='text/html') #at the moment the time value is hardcoded in the function just for simplicity
#app.route('/')
def index():
return render_template('test.html.jinja') # render a template at the index. The content will be embedded in this template
if __name__ == '__main__':
app.run(use_reloader=False)
then add an iframe where do you prefer in your html
<!doctype html>
<head>
<title>Title</title>
</head>
<body>
<h2> countdown </h2>
<div>
<iframe frameborder="0" noresize="noresize"
style='background: transparent; width: 100%; height:100%;' src="{{ url_for('content')}}"></iframe>
</div>
</body>
The result will be a dynamic countdown on your web-page
countdown
0123456789
you can see it done quick and dirty here on my repl
While it's not tuned around your application yet, (and not particularly beautiful graphically) you can modify the function to accept an input from the user with a form (I see you actually did already in your app), or also tune the countdown function directly.
t = request.form['t']
and adding to your html the form
<form method="post" action=".">
<p><input name="t" placeholder="your time"/></p>
<p><input type="submit" value="Submit"/></p>
</form>
You have the same route #app.route("/") appearing 3 times. The system will pick the first one which simply displays display.html. And I suspect even that will currently not work because your page is expecting values for message, timing but those attributes don't exist in your first route.
You should try something like
#app.route("/", methods=['POST', 'GET'])
def display():
page = 'display.html'
params = {"message":"", "timing":0} # initialize values for both message and timing. These will be returned when user loads the page (a GET call)
if request.method == 'POST':
timing = request.values.get("timing")
# do whatever processing you want
params["timing"] = <your computed value>
params["message"] = <your message>
params["message_2"] = <your other message>
return render_template(page, **params)
Delete all the other routes you have for #app.route("/")
I have exactly the same problem as this post
Python submitting webform using requests
but your answers do not solve it. When I execute this HTML file called api.htm in the browser, then for a second or so I see its page.
Then the browser shows the data I want with the URL https://api.someserver.com/api/ as as per the action below. But I want the data written to a file so I try the Python 2.7 script below.
But all I get is the source code of api.htm Please put me on the right track!
<html>
<body>
<form id="ID" method="post" action="https://api.someserver.com/api/ ">
<input type="hidden" name="key" value="passkey">
<input type="text" name="start" value ="2015-05-01">
<input type="text" name="end" value ="2015-05-31">
<input type="submit" value ="Submit">
</form>
<script type="text/javascript">
document.getElementById("ID").submit();
</script>
</body>
</html>
The code:
import urllib
import requests
def main():
try:
values = {'start' : '2015-05-01',
'end' : '2015-05-31'}
req=requests.post("http://my-api-page.com/api.htm",
data=urllib.urlencode(values))
filename = "datafile.csv"
output = open(filename,'wb')
output.write(req.text)
output.close()
return
main()
I can see several problems:
Your post target URL is incorrect. The form action attribute tells you where to post to:
<form id="ID" method="post" action="https://api.someserver.com/api/ ">
You are not including all the fields; type=hidden fields need to be posted too, but you are ignoring this one:
<input type="hidden" name="key" value="passkey">
Do not URL-encode your POST variables yourself; leave this to requests to do for you. By encoding yourself requests won't recognise that you are using an application/x-www-form-urlencoded content type as the body. Just pass in the dictionary as the data parameters and it'll be encoded for you and the header will be set.
You can also stream the response straight to a file object; this is helpful when the response is large. Switch on response streaming, make sure the underlying raw urllib3 file-like object decodes from transfer encoding and use shutil.copyfileobj to write to disk:
import requests
import shutil
def main():
values = {
'start': '2015-05-01',
'end': '2015-05-31',
'key': 'passkey',
}
req = requests.post("http://my-api-page.com/api.htm",
data=values, stream=True)
if req.status_code == 200:
with open("datafile.csv", 'wb') as output:
req.raw.decode_content = True
shutil.copyfileobj(req.raw, output)
There may still be issues with that key value however; perhaps the server sets a new value for each session, coupled with a cookie, for example. In that case you'd have to use a Session() object to preserve cookies, first do a GET request to the api.htm page, parse out the key hidden field value and only then post. If that is the case then using a tool like robobrowser might just be easier.
What is the simplest way to display the Python ystockquote (http://goldb.org/ystockquote.html) module output in HTML? I am creating an HTML dashboard which will be run locally on my computer and want to insert the stock output results into the designated HTML placeholders. I am hoping that because it is local I can avoid many CGI and server requirements.
I would use a templating system (see the Python wiki article). jinja is a good choice if you don't have any particular preferences. This would allow you to write HTML augmented with expansion of variables, control flow, etc. which greatly simplifies producing HTML automatically.
You can simply write the rendered HTML to a file and open it in a browser, which should prevent you from needing a webserver (though running python -m SimpleHTTPServer in the directory containing the HTML docs will make them available under http://localhost:8000)
Here is a simple server built using web.py (I have been playing with this for a while now, so this was a fun question to answer)
import web
import ystockquote
urls = (
'/', 'index'
)
app = web.application(urls, globals())
class index:
def POST(self):
history = ystockquote.get_historical_prices(web.input()['stock'], web.input()['start'], web.input()['end'])
head = history[0]
html = '<html><head><link href="//netdna.bootstrapcdn.com/twitter-bootstrap/2.3.1/css/bootstrap-combined.min.css" rel="stylesheet"><body><table class="table table-striped table-bordered table-hover"><thead><tr><th>{}<th>{}<th>{}<th>{}<th>{}<th>{}<th>{}<tbody>'.format(*head)
for row in history[1:]:
html += "<tr><td>{}<td>{}<td>{}<td>{}<td>{}<td>{}<td>{}".format(*row)
return html
def GET(self):
return """<html>
<head><link href='//netdna.bootstrapcdn.com/twitter-bootstrap/2.3.1/css/bootstrap-combined.min.css' rel='stylesheet'>
<body>
<form method='POST' action='/'><fieldset>
Symbol <input type='input' name='stock' value='GOOG'/><br/>
From <input type='input' name='start' value='20130101'/><br/>
To <input type='input' name='end' value='20130506'/><br/>
<input type='submit' class='btn'/></fieldset></form>"""
if __name__ == "__main__":
app.run()
I'm trying to get a HTML Gui on my simple SL4A Python app. the only thing I need to perform is ask the user for 1 input string at the start of my app.
For debugging purposes I started of simple. Unfortunately even this won't function.
Any idea's what's wrong here? (I've tried several pieces of code like this and all have the same issue)
Python code:
import android
loop = True
droid = android.Android()
droid.webViewShow('/sdcard/sl4a/scripts/screen.html')
while loop:
res = droid.waitForEvent('data')
if res:
print str(res)
HTML code
<html>
<head>
<script>
var droid = new Android();
var fiets = function() {
droid.postEvent("data", document.getElementById("gsm").value);
}
</script>
</head>
<body onload:"fiets()">
<form onsubmit="fiets(); return false;">
<label for="say">What would you like to say?</label>
<input type="text" id="gsm" value="99999999" />
<input type="submit" value="Store" />
</form>
</body>
</html>
the error message is repeatedly (the number 3114 is incremental):
java.lang.NullPointerException
Result(id=3114, result=None, error=u'java.lang.NullPointerException')
update:
http://www.mithril.com.au/android/doc/EventFacade.html
As we go I read waitForEvent is deprecated in r4. I should use eventWaitFor instead.
This takes the error away but doesn't make the example function. Python script prints nothing.
update2:
droid.postEvent should become droid.eventPost
droid.waitForEvent('data') should become droid.waitForEvent('data')
In javascript and python.
Problem Solved
I want user to enter a sentence then I break up that sentence into a list. I got the html page down but i have trouble passing that sentence to python.
How do I properly send the user input to be processed by python and output it to a new page?
There are many Python web frameworks. For example, to break up a sentence using bottle:
break-sentence.py:
#!/usr/bin/env python
from bottle import request, route, run, view
#route('/', method=['GET', 'POST'])
#view('form_template')
def index():
return dict(parts=request.forms.sentence.split(), # split on whitespace
show_form=request.method=='GET') # show form for get requests
run(host='localhost', port=8080)
And the template file form_template.tpl that is used both to show the form and the sentence parts after processing in Python (see index() function above):
<!DOCTYPE html>
<title>Break up sentence</title>
%if show_form:
<form action="/" method="post">
<label for="sentence">Input a sentence to break up</label>
<input type="text" name="sentence" />
</form>
%else:
Sentence parts:<ol>
%for part in parts:
<li> {{ part }}
%end
</ol>
%end
request.forms.sentence is used in Python to access user input from <input name="sentence"/> field.
To try it you could just download bottle.py and run:
$ python break-sentence.py
Bottle server starting up (using WSGIRefServer())...
Listening on http://localhost:8080/
Hit Ctrl-C to quit.
Now you can visit http://localhost:8080/.
Have you tried Google? This page sums up the possibilities, and is one of the first results when googling 'python html'.
As far as I know, the two easiest options for your problem are the following.
1) CGI scripting. You write a python script and configure it as a CGI-script (in case of most HTTP-servers by putting it in the cgi-bin/ folder). Next, you point to this file as the action-attribute of the form-tag in your HTML-file. The python-script will have access to all post-variables (and more), thus being able to process the input and write it as a HTML-file. Have a look at this page for a more extensive description. Googling for tutorials will give you easier step-by-step guides, such as this one.
2) Use Django. This is rather suited for larger projects, but giving it a try on this level may provide you certain insights, and wetting your appetite for future work ;)