report_server.py

import os
from ast import literal_eval
import tempfile
import subprocess

from flask import Flask, abort, request, Response
from flask.ext.mako import MakoTemplates, render_template

from destral.openerp import OpenERPService
from destral.transaction import Transaction

os.environ.update({
    'OPENERP_DB_NAME': '',
    'OPENERP_DB_USER': '',
    'OPENERP_DB_PASSWORD': '',
    'OPENERP_DB_HOST': '',
    'OPENERP_ADDONS_PATH': '',
    'OPENERP_ROOT_PATH': '',
    'OPENERP_MONGODB_NAME': '',
    'OPENERP_MONGODB_HOST': '',
    'EMPOWERING_COMPANY_ID': '',
    'EMPOWERING_DEBUG': '',
    'EMPOWERING_CERT_FILE': '',
    'EMPOWERING_KEY_FILE': ''
})


app = Flask(__name__)
mako = MakoTemplates(app)
app.template_folder = os.getcwd()


def arg_eval(var):
    try:
        return literal_eval(var)
    except Exception:
        return var


class RenderReport(object):
    def __init__(self, content):
        self.content = content
        self.html_file = tempfile.mkstemp(suffix='.html')[1]
        with open(self.html_file, 'w') as f:
            f.write(content)
        self.output = tempfile.mkstemp(suffix='.pdf')[1]
    
    def __enter__(self):
        return self

    def __exit__(self, exc_type, exc_val, exc_tb):
        os.unlink(self.html_file)
        os.unlink(self.output)

    def render(self):
        command = [
            'wkhtmltopdf',
            '--margin-top', '0',
            '--margin-bottom', '0',
            '--margin-left', '0',
            '--margin-right', '0',
            '--page-size', 'A4',
            '--orientation', 'Portrait',
            '--load-error-handling', 'ignore',
            self.html_file,
            self.output
        ]
        subprocess.call(command)
        with open(self.output, 'r') as f:
            return f.read()
        

@app.route('/<path:report>')
def index(report):
    app.logger.info('Rendering report: %s', report)
    if not os.path.exists(report):
        abort(404)
    args = {}
    for key, value in request.args.iteritems():
        args[key] = arg_eval(value)
    if 'ids' not in args:
        abort(404)
    if 'model' not in args:
        abort(404)
    service = OpenERPService()
    with Transaction().start(service.db_name) as txn:
        objects = service.pool.get(args['model']).browse(txn.cursor, txn.user, args['ids'])
        html =  render_template(report, objects=objects, **args)
        with RenderReport(html) as rnd:
            pdf = rnd.render()
            return Response(pdf, mimetype='application/pdf')


if __name__ == '__main__':
    app.run(debug=True)