Flask-WeasyPrint¶
Make PDF with WeasyPrint in your Flask app.
- BSD licensed
- Python 2.6, 2.7 and 3.3
- Latest documentation on python.org
- Source, issues and pull requests on Github
- Releases on PyPI
Installation¶
Once you have WeasyPrint installed and working, just install the extension with pip:
$ pip install Flask-WeasyPrint
Introduction¶
Let’s assume you have a Flask application serving an HTML document at http://example.net/hello/ with a print-ready CSS stylesheet. WeasyPrint can render this document to PDF:
from weasyprint import HTML
pdf = HTML('http://example.net/hello/').write_pdf()
WeasyPrint will fetch the stylesheet, the images as well as the document itself over HTTP, just like a web browser would. Of course, going through the network is a bit silly if WeasyPrint is running on the same server as the application. Flask-WeasyPrint can help:
from my_flask_application import app
from flask_weasyprint import HTML
with app.test_request_context(base_url='http://example.net/'):
# /hello/ is resolved relative to the context’s URL.
pdf = HTML('/hello/').write_pdf()
Just import HTML() or CSS()
from flask_weasyprint rather than weasyprint, and use them from
within a Flask request context.
For URLs below the application’s root URL, Flask-WeasyPrint will short-circuit
the network and make the request at the WSGI level, without leaving the
Python process.
Note that from a Flask view function you already are in a request context and
thus do not need test_request_context().
An example app¶
Here is a simple hello world application that uses Flask-WeasyPrint:
from flask import Flask, render_template, url_for
from flask_weasyprint import HTML, render_pdf
app = Flask(__name__)
@app.route('/hello/', defaults={'name': 'World'})
@app.route('/hello/<name>/')
def hello_html(name):
return render_template('hello.html', name=name)
@app.route('/hello_<name>.pdf')
def hello_pdf(name):
# Make a PDF from another view
return render_pdf(url_for('hello_html', name=name))
# Alternatively, if the PDF does not have a matching HTML page:
@app.route('/hello_<name>.pdf')
def hello_pdf(name):
# Make a PDF straight from HTML in a string.
html = render_template('hello.html', name=name)
return render_pdf(HTML(string=html))
templates/hello.html:
<!doctype html>
<title>Hello</title>
<link rel=stylesheet href="{{ url_for('static', filename='style.css') }}" />
<p>Hello, {{ name }}!</p>
<nav><a href="{{ url_for('hello_pdf', name=name) }}">Get as PDF</a></nav>
static/style.css:
body { font: 2em Fontin, serif }
nav { font-size: .7em }
@page { size: A5; margin: 1cm }
@media print {
nav { display: none }
}
render_pdf() helps making a Response with the correct
MIME type. You can give it an URL or an HTML object.
In the HTML you can use url_for() or relative URLs.
Flask-WeasyPrint will do the right thing to fetch resources and make
hyperlinks absolute in the PDF output.
In CSS, @page and @media print can be used to have print-specific
styles. Here the “Get as PDF” link is not displayed in the PDF itself,
although it still exists in the HTML.
API¶
-
flask_weasyprint.make_flask_url_dispatcher()[source]¶ Return an URL dispatcher based on the current request context.
You generally don’t need to call this directly.
The context is used when the dispatcher is first created but not afterwards. It is not required after this function has returned.
Dispatch to the context’s app URLs below the context’s root URL. If the app has a
SERVER_NAMEconfig, also accept URLs that have that domain name or a subdomain thereof.
-
flask_weasyprint.make_url_fetcher(dispatcher=None, next_fetcher=weasyprint.default_url_fetcher)[source]¶ Return an function suitable as a
url_fetcherin WeasyPrint. You generally don’t need to call this directly.If
dispatcheris not provided,make_flask_url_dispatcher()is called to get one. This requires a request context.Otherwise, it must be a callable that take an URL and return either
Noneor a(wsgi_callable, base_url, path)tuple. For Nonenext_fetcheris used. (By default, fetch normally over the network.) For a tuple the request is made at the WSGI level.wsgi_callablemust be a Flask application or another WSGI callable.base_urlis the root URL for the application whilepathis the path within the application. Typicallybase_url + pathis equal or equivalent to the passed URL.
-
flask_weasyprint.HTML(guess=None, **kwargs)[source]¶ Like weasyprint.HTML() but:
make_url_fetcher()is used to create anurl_fetcher- If
guessis not a file object, it is an URL relative to the current request context. This means that you can just pass a result fromflask.url_for(). - If
stringis passed,base_urldefaults to the current request’s URL.
This requires a Flask request context.
-
flask_weasyprint.CSS(guess=None, **kwargs)[source]¶ Like weasyprint.CSS() but:
make_url_fetcher()is used to create anurl_fetcher- If
guessis not a file object, it is an URL relative to the current request context. This means that you can just pass a result fromflask.url_for(). - If
stringis passed,base_urldefaults to the current request’s URL.
This requires a Flask request context.
-
flask_weasyprint.render_pdf(html, stylesheets=None, download_filename=None)[source]¶ Render a PDF to a response with the correct
Content-Typeheader.Parameters: - html – Either a
weasyprint.HTMLobject or an URL to be passed toflask_weasyprint.HTML(). The latter case requires a request context. - stylesheets – A list of user stylesheets, passed to
write_pdf() - download_filename – If provided, the
Content-Dispositionheader is set so that most web browser will show the “Save as…” dialog with the value as the default filename.
Returns: a
flask.Responseobject.- html – Either a
