Below example gives u an idea. 

In main.py

from odoo import models, fields, api

from werkzeug import url_encode

class SimpleControllerModel(models.Model):

    _name ="simple.controller"

    name = fields.Char(string="name")

    age = fields.Integer(string="age")

    designation = fields.Selection([('sw','software'),('salesman','Salesman')])

    @api.multi

    def webpage(self):

        values = dict(self._context.get('params', {}))

        print dict(self._context.get('params',{}))

        values.update({

            'model': self._name,

            'id': self.id

#        HERE PASS THE VALUES U NEED.      ID is passed along with the context.

            })

        return{

               'type': 'ir.actions.act_url',

               'target': 'self',

               'url': '/details/employee/%s/%s' % (self.name,self.id)

#             'url': '/details/employee/%s/%s' % (self.id,url_encode(values))

               }

Then Define  Controller: Like below

from odoo import http

from odoo.http import request

class SimpleController(http.Controller):

#    @http.route(["/details/employee"],type='http',auth="user",methods=['GET'],website=True)

    @http.route(['/details/employee/<model("simple.controller"):name>',

                 '/details/employee/<model("simple.controller"):name>/<model("simple.controller"):id>',

                 '/details/employee/<string:id>',

                 '/details/employee'],

                type='http',auth="public",methods=['GET'],website=True)

    def view(self,name,**kwargs):

        print "controllerview"

        if kwargs.get('model', False) == 'simple.controller':

                action_xml_id = 'simple_controller.action_simple_controller'

        action_id = request.env.ref(action_xml_id).id

        kwargs.update({

                'action': action_id,

            })

        values = dict(kwargs)

        return request.render('simple_controller.simple_controller_templateid', values)

In template.xml.. Define below code

<odoo>

<template id="simple_controller.simple_controller_templateid" name="simple_controller">

    <t t-call="website.layout">

    <div class="pull-left css_editable_mode_hidden">

                <ul class="list-inline">

                    <li>

                        <a class="btn btn-danger"

                            t-att-href="'/web#return_label=Website&amp;model=%s&amp;id=%s&amp;action=%s&amp;view_type=form' % (model, id, action)">

                            <span class="fa fa-long-arrow-left" />

                            Back

                            <span t-esc="test" />

                        </a>

                    </li>

                </ul>

            </div>

    </t>

</template>

</odoo>