I'm trying to save a chart by converting SVG to PNG with a Python script.
So I start storing the svg data in a variable with :
var svgdata = Ext.draw.engine.SvgExporter.generate(chart.surface);
When I do alert(svgdata), I can see that this output is correct.
But when I send it to the server like this :
Ext.draw.engine.ImageExporter.defaultUrl = "data/svg_to_png.py?svgdata="+svgdata;
The svgdata that has been sent looks like this :
<?xml version=
I'm new to extjs, please help me on this one. What is the right way to send svg data to my python script and render a png image ?
This is my python script :
import cairo
import cgi
import rsvg
print "Content-type: image/png\n\n"
arguments = cgi.FieldStorage()
img = cairo.ImageSurface(cairo.FORMAT_ARGB32, 640,480)
ctx = cairo.Context(img)
handler= rsvg.Handle(None, str(arguments["svgdata"]))
handler.render_cairo(ctx)
img.write_to_png("svg.png")
HELP ME PLEASE!
<div style="display:none;">
<iframe id="file_download_iframe" src="blank.html"></iframe>
</div>
You will need a blank html page on your server for this to work properly in all browsers. Basically the blank.html page is an empty page to satisfy that the ifram always has a page in it.
Then you need a basic form hidden somewhere too:
<div style="display:none;">
<form
id = "file_download_iframe_form"
name = "file_download_iframe_form"
target = "file_download_iframe"
method = "post"
action = "data/svg_to_png.py"
>
<input type="hidden" id="svgdata" name="svgdata"/>
</form>
</div>
Then have a javascript function like this:
function getImage(svgdata){
var form = document.getElementById("file_download_iframe_form");
document.getElementById("svgdata").value = svgdata;
form.submit();
};
Related
I wonder if someone can help me. I'm trying to do something like the following to get input events from a HTML text box and send them to a python function.
textarea = cgi.FieldStorage()
chars = textarea.getvalue('1')
def MyPythonFunction():
'Do something with chars'
print(<textarea oninput=MyPythonFunction() </textarea>)
I've tried all kinds of things but can't get it to work.
Thanks in advance
First, the oninput keyword of the textarea HTML tag expects JavaScript code and would interpret mypythonfunction to be a JavaScript function. You need to output an HTML form that contains a SUBMIT tag such that when the form is submitted it invokes your server-side script: the form might look like:
<form name="f" action="my_script.py" method="post">
<textarea name="chars"></textarea>
<br>
<input type="submit" name="submit" value="Submit">
</form>
Your server side script, my_script.py, which must be executable, might look like:
#!/usr/bin/env python
import cgi
import cgitb
cgitb.enable()
form = cgi.FieldStorage()
chars = form.getvalue('chars')
If you really wanted to process input a character at a time, then you would remove the SUBMIT HTML tag, put back the oninput keyword. But then you would have to specify a JavaScript function that would get invoked whenever the contents of the textarea changed. This function would have to use a technique called AJAX to invoke your server-side Python script passing the contents of the TEXTAREA as an argument. This is a rather advanced topic, but you can investigate this.
I have a Flask server and I want to render a base64 image in HTML page.
Flask Code:
new_image_string = base64.b64encode(buff.getvalue()).decode("utf-8")
return render_template('perspective_result.html', img_data=new_image_string)
HTML CODE:
<img src="data:image/jpeg;base64,+img_data" alt="img_data" id="imgslot"/>
I am getting the below error from browser console:
GET data:image/jpeg;base64,+img_data 0 ()
Where did I go wrong?
<img src="data:image/jpeg;base64,{{ img_data }}" alt="img_data" id="imgslot"/>
This is the way we can solve this.
1.First Add A empty Image Tag Without A Source
2.Then With Javascript preprocess the base64 data string
3.update the Image src with updated base64 data
<img src="" id="img" alt="Chart" height="100" width="100">
<script>
data = "{{data}}"
data = data.replace("b'", "") //to get rid of start curly brace code
data = data.replace("'", "") //to get rid of end curly bracecode
document.getElementById("img").src = "data:image/png;base64,"+data; // set src
</script>
I'm trying to show some badge images I made for a RANK APP I've been working for. It's 10 images that should be shown specific for each driver.
I'm not an expert on coding, but I keep searching and studying ways to solve the problem I've been through.
I firstly tried to send base64 images from the API to the browser, using this code:
<!-- language: python -->
for img in imglist: #loop for creating a list of base64 images from a list of image dir.
imgcode = base64.encodestring(open(imgdir + img,"rb").read())
imgcodelist.append(imgcode)
for driver in sortdriverList: #loop for taking drivers points and turn it into RANK img
if (driver['Races'] < 21):
driver['Rank'] = str(imgcodelist[9])
[...]
The second loop is longer than that, stil what I've shown to you above makes any driver that wasn't participating in more than 21 races, be part of a 'NON CLASSIFIED' badge.
I used AngularJS to try to show the base64 image using the code below.
'<html>'
<td><img src="data:image/png;base64,{{ '{{driver.Rank}}'}}"></td>
[driver.Rank] should be the base64 code string. When I run the app, the image is not shown, instead I see the very code of the image inside the table =/
Then I tried to turn [driver.Rank] into a dir string for "img src=", using the codes below.
<!-- language: python -->
imglist = ["notclassified.png", etc...]
imgdir = "static/images/"
for item in sortdriverList:
if (item['Races'] < 21):
item['Points'] = imgdir + imglist[9]
and in my HTML I changed the img src to:
'<html>'
<img src= {{ '{{driver.Rank}}' }}>
and now it shows the directory of the images.
I've been searching for CSS ways to make it possible.
I coudn't find a solution yet.
It's hard to tell what's going on since only segments are pasted, but I'm guessing it has to do with how you are escaping the code. Maybe you could paste the generated code in chrome.
Sometimes seeing a working example helps.
angular.module('App', [])
.controller('DriverCtrl', DriverCtrl);
function DriverCtrl($scope) {
// base64 encode 1x1 black pixel
this.Rank = 'R0lGODlhAQABAIAAAAUEBAAAACwAAAAAAQABAAACAkQBADs=';
}
<div ng-app="App">
<div ng-controller="DriverCtrl as driver">
<div>Rank: {{driver.Rank}}</div>
<span>Image:</span>
<img ng-src="data:image/png;base64,{{driver.Rank}}">
</div>
</div>
<script src="https://ajax.googleapis.com/ajax/libs/angularjs/1.2.23/angular.min.js"></script>
I am trying to fill in a html form using python code, the idea is that an agent sends data to the html webpage. After that another python script collects the data (cgi is used). I tried quite some options but I am not able to change the value of the form named 'os' using the agent script. When I fill in the form by hand everything works well and the collector takes over.
If more information is needed i happely provide it.
I hope someone can help me.
Agent script:
import requests
url = 'http://127.0.0.1/PythonApp/website.html'
data = {'os':'test12345'}
session = requests.session()
r = requests.post(url, data)
print(r.status_code, r.reason)
print(r.text)
HTML page:
<html>
<head>Text</head>
<body>
<form action="postmethod.py" method="POST">
<input type="text" name="os" value="abc">
</form>
</body>
</html>
Collector (postmethod.py):
import cgi
# print header
print("Content-type: text/html\n\n")
print("<h2>Arguments</h2>")
form = cgi.FieldStorage()
arg1 = str(form.getvalue('os'))
miauw = ("os: " +arg1+"<br>")
print(miauw)
I am creating a Google App Engine web application written in Python, and I would like to create a drop down box that displays different values corresponding to pages of a book that a user could choose from. I would like the action of the drop down box to be to direct the user to the page that corresponds to this link:
<a href='/viewpage/{{bookpage.key}}'>{{ bookpage.page }} </a>
The "bookpage" entity is passed to the html
Thank you!
David
Use a Jump Menu. Here is a pretty straight forward implementation.
Basically you'll just add a bit of JavaScript, and instead of writing an a tag, you'll write an option:
<option value='/viewpage/{{bookpage.key}}'>{{ bookpage.page }} </option>
What about <option value='/viewpage/{{bookpage.key.id}}'>{{bookpage.page}}</option>?
I hope it's not a dumb answer.
I'm not familiar with the google-app-engine but, the following javascript seems to do what you want. The python could generate the array variables on the server side, and then everything else would work properly.
I included the hardcoded arrays so you can see what is going on, but you can replace the arrays with the python code(assuming bookpage is some kind of dictionary):
i = 0
for bp in bookpage.keys():
print("mysites["+str(i)+"] = "+ bookpage[bp])+";"
print("sitenames["+str(i)+"] = "+sitenames[bp])+";"
i+=1
<html>
<body>
<script type="text/javascript">
var mysites= new Array();
mysites[0] = "http://www.google.com"; //Generate this line with python
mysites[1] = "http://www.bing.com"; //Generate this line with python
mysites[2] = "http://www.yahoo.com"; //Generate this line with python
var sitenames = new Array();
sitenames[0] = "Google"; //Generate this line with python
sitenames[1] = "Bing"; //Generate this line with python
sitenames[2] = "Yahoo"; //Generate this line with python
function changeLink(){
var index = document.getElementById("theselect").selectedIndex
document.getElementById("thelink").innerHTML=index;
var newlink = mysites[index];
var newstring = sitenames[index];
document.getElementById("thelink").href=newlink;
document.getElementById("thelink").innerHTML=sitenames[index];
}
</script>
<select id="theselect" onclick="changeLink()">
<option>Google</option>
<option>Bing</option>
<option>Yahoo</option>
</select>
<br />
<a id="thelink" href="http://www.google.com" > Google </a>
</body>
</html>
Clicking on the option box calls the changeLink() function, which then changes the link and the inner html of the tag.