Setting up a calendar server with Plone 2

by Kamon Ayeva — last modified Dec 06, 2009 09:27 PM
How to configure Plone as an iCal server.

Objective

Use Plone 2 and a few open source components to build an iCalendar server.

What is iCalendar

Short answer : iCalendar is a standard text file format for calendar files.

Long answer : Internet Calendaring and Scheduling Core Object Specification (iCalendar) - read the RFC 2445 ;)

What is PloneiCalendar

PloneiCalendar is a simple product designed by Ingeniweb to handle calendar files in Plone.

It is based on the iCalendar file format. iCalendar can be used to transport personal calendaring information between applications of your choice whether they are personal information managers, email systems or web browsers.

Once an iCalendar is created in plone, you can share it with other users or groups, keep it private or modify it by using standard calendar applications like mozilla calendar or ical.

The iCalendar view allows user to view the calendar by launching the default application for calendar files or download the file.

What you need

Server side :

Client side :

or

(or Ximian Evolution or KOrganizer or whatever - may be even Outlook ;) )

Starting a webdav server

To allow webdav transaction in zope you will have to put these line in zope.conf : 

    <webdav-source-server>

      address myical-dav.domain.com:8090

      force-connection-close off

    </webdav-source-server>

DNS & Apache configuration

Assuming you have 2 hosts declared in your DNS for your box :

  • myical.domain.com

and

  • myical-dav.domain.com

Configure your Apache, so that, to access your website, one use this link : 

    myical.domain.com 8080

and use the webdav server, one have this : 

    myical-dav.domain.com to port 8090

Installation

Plone 2 :

Install Plone2.

PloneiCalendar :

Untar the product in the Product folder of zope.

Install PloneiCalendar. The installation is fully automatic, use the quickinstaller tool.

Settings

To return a correct link to webdav server, you have to customize the ics_url.py python script in iCalendar skin. In portal_skins/ploneicalendar/ics_url.py click on customize.

Original script is : 

    from string import replace

    url = context.absolute_url()

    return replace(url, 'http', 'webcal')

Replace it by : 

    from string import replace

    url = context.absolute_url()

    url = replace(url, 'http', 'webcal')

    return replace(url, 'myical.', 'myical-dav.')

This will return an url like that : 

    webcal://mycal-dav.domain.com/

What does the installation do

At the installation of the product, two roles are created : LocalReader and LocalWriter.

These roles will be used as local roles, to allow access to icalendar products in plone.

How does it work

It works like a classic file in plone.

Go in the user folder. Add an iCalendar.

Fill in the form :

Give a title, it will be the name of your iCalendar.

Give a short description.

Upload an existing ics file (if any)

Note that all fields are optionnal. If no title is given, a random id is generated. If no ics file is given, the product proposes an virgin ics file.

Share my Calendar

You can share your iCalendar. Click on sharing. This screen is showing the users or the groups that have local permissions on your iCalendar.

Permissions :

  • LocalReader can only see an icalendar but cannot modify it.
  • LocalWriter can see and modify an icalendar.

Note that when you create an icalendar, you are shown in sharing view as LocalWriter.

You can choose to assign local roles to group or to users.

NB : This screen is NOT the sharing tab of Plone 2; it's a simplified and specialiserd version for PloneiCalendar

View my iCalendar

There are several ways to see an iCalendar.

Plone :

In iCalendar View, the link "Click here to view the file". It launches the default application to see calendar files.

Use an application :

If you are on Apple, use ical else you can use Mozilla Calendar. The two applications are the same, at the difference that mozilla calendar can read and write on a calendar, and iCal can only read or write on it.

Modify my icalendar

To modify your iCalendar, you must have LocalWriter role (read : you must own this calendar or be allowed by its owner to write into it)

  • with Mozilla Calendar :

    Click to view the iCalendar and modify it. Do not forget to publish it.

  • with iCal :

    You have to subscribe to an iCalendar (with its webdav url).

Future - Roadmap

Next version of PloneiCalendar will integrate a parser and display calendar-based content directly into Plone. Any volunteers welcome !

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