For my django powered site, I am looking for an easy solution to convert dynamic html pages to pdf.
Pages include HTML and charts from Google visualization API (which is javascript based, yet including those graphs is a must).
This question is related to
python
html
django
pdf
pdf-generation
You can use iReport editor to define the layout, and publish the report in jasper reports server. After publish you can invoke the rest api to get the results.
Here is the test of the functionality:
from django.test import TestCase
from x_reports_jasper.models import JasperServerClient
"""
to try integraction with jasper server through rest
"""
class TestJasperServerClient(TestCase):
# define required objects for tests
def setUp(self):
# load the connection to remote server
try:
self.j_url = "http://127.0.0.1:8080/jasperserver"
self.j_user = "jasperadmin"
self.j_pass = "jasperadmin"
self.client = JasperServerClient.create_client(self.j_url,self.j_user,self.j_pass)
except Exception, e:
# if errors could not execute test given prerrequisites
raise
# test exception when server data is invalid
def test_login_to_invalid_address_should_raise(self):
self.assertRaises(Exception,JasperServerClient.create_client, "http://127.0.0.1:9090/jasperserver",self.j_user,self.j_pass)
# test execute existent report in server
def test_get_report(self):
r_resource_path = "/reports/<PathToPublishedReport>"
r_format = "pdf"
r_params = {'PARAM_TO_REPORT':"1",}
#resource_meta = client.load_resource_metadata( rep_resource_path )
[uuid,out_mime,out_data] = self.client.generate_report(r_resource_path,r_format,r_params)
self.assertIsNotNone(uuid)
And here is an example of the invocation implementation:
from django.db import models
import requests
import sys
from xml.etree import ElementTree
import logging
# module logger definition
logger = logging.getLogger(__name__)
# Create your models here.
class JasperServerClient(models.Manager):
def __handle_exception(self, exception_root, exception_id, exec_info ):
type, value, traceback = exec_info
raise JasperServerClientError(exception_root, exception_id), None, traceback
# 01: REPORT-METADATA
# get resource description to generate the report
def __handle_report_metadata(self, rep_resourcepath):
l_path_base_resource = "/rest/resource"
l_path = self.j_url + l_path_base_resource
logger.info( "metadata (begin) [path=%s%s]" %( l_path ,rep_resourcepath) )
resource_response = None
try:
resource_response = requests.get( "%s%s" %( l_path ,rep_resourcepath) , cookies = self.login_response.cookies)
except Exception, e:
self.__handle_exception(e, "REPORT_METADATA:CALL_ERROR", sys.exc_info())
resource_response_dom = None
try:
# parse to dom and set parameters
logger.debug( " - response [data=%s]" %( resource_response.text) )
resource_response_dom = ElementTree.fromstring(resource_response.text)
datum = ""
for node in resource_response_dom.getiterator():
datum = "%s<br />%s - %s" % (datum, node.tag, node.text)
logger.debug( " - response [xml=%s]" %( datum ) )
#
self.resource_response_payload= resource_response.text
logger.info( "metadata (end) ")
except Exception, e:
logger.error( "metadata (error) [%s]" % (e))
self.__handle_exception(e, "REPORT_METADATA:PARSE_ERROR", sys.exc_info())
# 02: REPORT-PARAMS
def __add_report_params(self, metadata_text, params ):
if(type(params) != dict):
raise TypeError("Invalid parameters to report")
else:
logger.info( "add-params (begin) []" )
#copy parameters
l_params = {}
for k,v in params.items():
l_params[k]=v
# get the payload metadata
metadata_dom = ElementTree.fromstring(metadata_text)
# add attributes to payload metadata
root = metadata_dom #('report'):
for k,v in l_params.items():
param_dom_element = ElementTree.Element('parameter')
param_dom_element.attrib["name"] = k
param_dom_element.text = v
root.append(param_dom_element)
#
metadata_modified_text =ElementTree.tostring(metadata_dom, encoding='utf8', method='xml')
logger.info( "add-params (end) [payload-xml=%s]" %( metadata_modified_text ) )
return metadata_modified_text
# 03: REPORT-REQUEST-CALL
# call to generate the report
def __handle_report_request(self, rep_resourcepath, rep_format, rep_params):
# add parameters
self.resource_response_payload = self.__add_report_params(self.resource_response_payload,rep_params)
# send report request
l_path_base_genreport = "/rest/report"
l_path = self.j_url + l_path_base_genreport
logger.info( "report-request (begin) [path=%s%s]" %( l_path ,rep_resourcepath) )
genreport_response = None
try:
genreport_response = requests.put( "%s%s?RUN_OUTPUT_FORMAT=%s" %(l_path,rep_resourcepath,rep_format),data=self.resource_response_payload, cookies = self.login_response.cookies )
logger.info( " - send-operation-result [value=%s]" %( genreport_response.text) )
except Exception,e:
self.__handle_exception(e, "REPORT_REQUEST:CALL_ERROR", sys.exc_info())
# parse the uuid of the requested report
genreport_response_dom = None
try:
genreport_response_dom = ElementTree.fromstring(genreport_response.text)
for node in genreport_response_dom.findall("uuid"):
datum = "%s" % (node.text)
genreport_uuid = datum
for node in genreport_response_dom.findall("file/[@type]"):
datum = "%s" % (node.text)
genreport_mime = datum
logger.info( "report-request (end) [uuid=%s,mime=%s]" %( genreport_uuid, genreport_mime) )
return [genreport_uuid,genreport_mime]
except Exception,e:
self.__handle_exception(e, "REPORT_REQUEST:PARSE_ERROR", sys.exc_info())
# 04: REPORT-RETRIEVE RESULTS
def __handle_report_reply(self, genreport_uuid ):
l_path_base_getresult = "/rest/report"
l_path = self.j_url + l_path_base_getresult
logger.info( "report-reply (begin) [uuid=%s,path=%s]" %( genreport_uuid,l_path) )
getresult_response = requests.get( "%s%s/%s?file=report" %(self.j_url,l_path_base_getresult,genreport_uuid),data=self.resource_response_payload, cookies = self.login_response.cookies )
l_result_header_mime =getresult_response.headers['Content-Type']
logger.info( "report-reply (end) [uuid=%s,mime=%s]" %( genreport_uuid, l_result_header_mime) )
return [l_result_header_mime, getresult_response.content]
# public methods ---------------------------------------
# tries the authentication with jasperserver throug rest
def login(self, j_url, j_user,j_pass):
self.j_url= j_url
l_path_base_auth = "/rest/login"
l_path = self.j_url + l_path_base_auth
logger.info( "login (begin) [path=%s]" %( l_path) )
try:
self.login_response = requests.post(l_path , params = {
'j_username':j_user,
'j_password':j_pass
})
if( requests.codes.ok != self.login_response.status_code ):
self.login_response.raise_for_status()
logger.info( "login (end)" )
return True
# see http://blog.ianbicking.org/2007/09/12/re-raising-exceptions/
except Exception, e:
logger.error("login (error) [e=%s]" % e )
self.__handle_exception(e, "LOGIN:CALL_ERROR",sys.exc_info())
#raise
def generate_report(self, rep_resourcepath,rep_format,rep_params):
self.__handle_report_metadata(rep_resourcepath)
[uuid,mime] = self.__handle_report_request(rep_resourcepath, rep_format,rep_params)
# TODO: how to handle async?
[out_mime,out_data] = self.__handle_report_reply(uuid)
return [uuid,out_mime,out_data]
@staticmethod
def create_client(j_url, j_user, j_pass):
client = JasperServerClient()
login_res = client.login( j_url, j_user, j_pass )
return client
class JasperServerClientError(Exception):
def __init__(self,exception_root,reason_id,reason_message=None):
super(JasperServerClientError, self).__init__(str(reason_message))
self.code = reason_id
self.description = str(exception_root) + " " + str(reason_message)
def __str__(self):
return self.code + " " + self.description
I get the code to generate the PDF from html template :
import os
from weasyprint import HTML
from django.template import Template, Context
from django.http import HttpResponse
def generate_pdf(self, report_id):
# Render HTML into memory and get the template firstly
template_file_loc = os.path.join(os.path.dirname(__file__), os.pardir, 'templates', 'the_template_pdf_generator.html')
template_contents = read_all_as_str(template_file_loc)
render_template = Template(template_contents)
#rendering_map is the dict for params in the template
render_definition = Context(rendering_map)
render_output = render_template.render(render_definition)
# Using Rendered HTML to generate PDF
response = HttpResponse(content_type='application/pdf')
response['Content-Disposition'] = 'attachment; filename=%s-%s-%s.pdf' % \
('topic-test','topic-test', '2018-05-04')
# Generate PDF
pdf_doc = HTML(string=render_output).render()
pdf_doc.pages[0].height = pdf_doc.pages[0]._page_box.children[0].children[
0].height # Make PDF file as single page file
pdf_doc.write_pdf(response)
return response
def read_all_as_str(self, file_loc, read_method='r'):
if file_exists(file_loc):
handler = open(file_loc, read_method)
contents = handler.read()
handler.close()
return contents
else:
return 'file not exist'
I just whipped this up for CBV. Not used in production but generates a PDF for me. Probably needs work for the error reporting side of things but does the trick so far.
import StringIO
from cgi import escape
from xhtml2pdf import pisa
from django.http import HttpResponse
from django.template.response import TemplateResponse
from django.views.generic import TemplateView
class PDFTemplateResponse(TemplateResponse):
def generate_pdf(self, retval):
html = self.content
result = StringIO.StringIO()
rendering = pisa.pisaDocument(StringIO.StringIO(html.encode("ISO-8859-1")), result)
if rendering.err:
return HttpResponse('We had some errors<pre>%s</pre>' % escape(html))
else:
self.content = result.getvalue()
def __init__(self, *args, **kwargs):
super(PDFTemplateResponse, self).__init__(*args, mimetype='application/pdf', **kwargs)
self.add_post_render_callback(self.generate_pdf)
class PDFTemplateView(TemplateView):
response_class = PDFTemplateResponse
Used like:
class MyPdfView(PDFTemplateView):
template_name = 'things/pdf.html'
After trying to get this to work for too many hours, I finally found this: https://github.com/vierno/django-xhtml2pdf
It's a fork of https://github.com/chrisglass/django-xhtml2pdf that provides a mixin for a generic class-based view. I used it like this:
# views.py
from django_xhtml2pdf.views import PdfMixin
class GroupPDFGenerate(PdfMixin, DetailView):
model = PeerGroupSignIn
template_name = 'groups/pdf.html'
# templates/groups/pdf.html
<html>
<style>
@page { your xhtml2pdf pisa PDF parameters }
</style>
</head>
<body>
<div id="header_content"> (this is defined in the style section)
<h1>{{ peergroupsignin.this_group_title }}</h1>
...
Use the model name you defined in your view in all lowercase when populating the template fields. Because its a GCBV, you can just call it as '.as_view' in your urls.py:
# urls.py (using url namespaces defined in the main urls.py file)
url(
regex=r"^(?P<pk>\d+)/generate_pdf/$",
view=views.GroupPDFGenerate.as_view(),
name="generate_pdf",
),
Try wkhtmltopdf with either one of the following wrappers
django-wkhtmltopdf or python-pdfkit
This worked great for me,supports javascript and css or anything for that matter which a webkit browser supports.
For more detailed tutorial please see this blog post
If you have context data along with css and js in your html template. Than you have good option to use pdfjs.
In your code you can use like this.
from django.template.loader import get_template
import pdfkit
from django.conf import settings
context={....}
template = get_template('reports/products.html')
html_string = template.render(context)
pdfkit.from_string(html_string, os.path.join(settings.BASE_DIR, "media", 'products_report-%s.pdf'%(id)))
In your HTML you can link extranal or internal css and js, it will generate best quality of pdf.
https://github.com/nigma/django-easy-pdf
Template:
{% extends "easy_pdf/base.html" %}
{% block content %}
<div id="content">
<h1>Hi there!</h1>
</div>
{% endblock %}
View:
from easy_pdf.views import PDFTemplateView
class HelloPDFView(PDFTemplateView):
template_name = "hello.html"
If you want to use django-easy-pdf on Python 3 check the solution suggested here.
Source: Stackoverflow.com