HTML Rendering with Twisted.Web
Hello, I've asked a question before about using Jinja2 with Twisted.Web, but now I have a more general question about rendering HTML docs within a Twisted web application. All the examples on TwistedMatrix.com and the txTemplate adapter show that you pass the web page by either returning it as a string from render_Get or as a param in .render(). Is this true for all cases? This seems a bit inefficient when you have a file larger than <html><body> Hello, World!</body></html>. I've written an HTML file complete with .css and .js. How to I pass that document to my Twisted.Web resource? When I use the code below, the context replaces all markup from my HTML file. How do I get around this? How do you pass a larger HTML file to Twisted.Web? # -*- coding: utf-8 -* import os, sys from twisted.application import internet from twisted.web.resource import Resource from twisted.web import server from twisted.internet import reactor import txtemplate TEMPLATE_DIR = os.path.join(os.path.dirname(os.path.abspath(__file__)),"templates") class ThreadResource(Resource): def __init__(self): resource.Resource.__init__(self) self.loader = txtemplate.Jinja2TemplateLoader(TEMPLATE_DIR) def getChild(self, name, request): return self def render_GET(self, request): template_name = "base.html" template = self.loader.load(template_name) context = {"greeting": "Enter"} def cb(content): request.write(content) request.setResponseCode(200) request.finish() d = template.render(**context) d.addCallback(cb) return server.NOT_DONE_YET site = server.Site(ThreadResource()) reactor.listenTCP(8888, site) reactor.run()
Hi Jo, On Jun 26, 2013, at 10:52 AM, Jo as Queeniebee wrote:
Hello,
I've asked a question before about using Jinja2 with Twisted.Web, but now I have a more general question about rendering HTML docs within a Twisted web application.
All the examples on TwistedMatrix.com and the txTemplate adapter show that you pass the web page by either returning it as a string from render_Get or as a param in .render(). Is this true for all cases?
A Resource should either directly return bytes from a render* method, OR, return twisted.web.server.NOT_DONE_YET to indicate an asynchronous response will be returned *at some point*. API: http://twistedmatrix.com/documents/current/api/twisted.web.resource.IResourc... Also, these howtos may be useful to clarify the concept: http://twistedmatrix.com/documents/current/web/howto/web-in-60/asynchronous.... http://twistedmatrix.com/documents/current/web/howto/web-in-60/asynchronous-... If you're just loading up a template from disk and rendering it with local data, you may find that synchronous load/render/return works fine. If you find that you are blocking the web server from servicing other requests because you are querying a database, or fetching something from a remote service or something, then you'll want to go the asynchronous route. (Note that in your code below, there is really no reason to do it asynchronously)
This seems a bit inefficient when you have a file larger than <html><body> Hello, World!</body></html>.
If you are planning on streaming large amounts of data, then Twisted's producer/consumer api may be helpful: http://twistedmatrix.com/documents/current/core/howto/producers.html
I've written an HTML file complete with .css and .js. How to I pass that document to my Twisted.Web resource? When I use the code below, the context replaces all markup from my HTML file. How do I get around this? How do you pass a larger HTML file to Twisted.Web?
# -*- coding: utf-8 -*
import os, sys
from twisted.application import internet from twisted.web.resource import Resource from twisted.web import server from twisted.internet import reactor
import txtemplate
TEMPLATE_DIR = os.path.join(os.path.dirname(os.path.abspath(__file__)),"templates")
class ThreadResource(Resource): def __init__(self): resource.Resource.__init__(self) self.loader = txtemplate.Jinja2TemplateLoader(TEMPLATE_DIR)
def getChild(self, name, request): return self
def render_GET(self, request): template_name = "base.html" template = self.loader.load(template_name) context = {"greeting": "Enter"}
def cb(content): request.write(content) request.setResponseCode(200) request.finish()
d = template.render(**context) d.addCallback(cb) return server.NOT_DONE_YET
site = server.Site(ThreadResource()) reactor.listenTCP(8888, site) reactor.run() _______________________________________________
Your code looks fine (w/ a minor fixup in __init__). I did a quick test using your code and the context rendered fine. e.g. in 'base.html' I just have: Greeting: {{ greeting }} Maybe your template is malformed? Lucas
participants (2)
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Jo as Queeniebee -
Lucas Taylor