Integrating Outlook Calendar to Website / Other - php

Question

When the users add events to the online calendar they also can be added to the outlook calendar (synchronize). Obviously a site built using PHP can not integrate with desktop application directly, so I am looking alternative options.
Options I found:
Using PHP ICAL library creates an .ics file and the user can download it and install. Not the most user friendly way of doing it, might work.
Use SharePoint or exchange server- but have no previous experience working Microsoft technologies, so it not ideal.
Use Google Calendar and Zend Library (gdata), create online calendar and add events to that. Then using Google Calendar Sync tool the user can sync the online calendar to outlook. But the problem here is the all users need a gmail account to use the Sync tool, it not ideal when you have thousands of users on the site. Unless I create one global gmail account and create many calendars on that account, if that even possible.
Questions:
Are there any outlook plug-ins paid or free (ideally) that can achieve this?
Are there any web service/ APIs that can achieve this?
Any other ideas or solutions?

Answer 1

Office 365 comes with an REST API that can be used to read/write to calendars.
Here's some documentation on this. http://msdn.microsoft.com/office/office365/api/calendar-rest-operations
Alternatively, the EWS Managed API might be able to help you: http://msdn.microsoft.com/en-us/library/office/dd633696(v=exchg.80).aspx and
http://msdn.microsoft.com/en-us/library/office/dd633702(v=exchg.80).aspx

Answer 2

you could do this by having the outlook subscribe to the online calendar.
with phpicalendar you can have other clients subscribe to your calendars (here)
you may want to tweak the generated .ics file to include X-PUBLISHED-TTL - Recommended update interval for subscription to the calendar

Answer 3

To get the calender event follow these step:
Sign in to Calendar
On the toolbar, click Share
Select the calendar that you want to export/embed.
Click Get a link.
Under Show event details (click Create)
Note: If step number 5 is already performed, just skip it and click Link to event details
Copy the link that you needed and paste it on the desired program/website.

Answer 4

Use EWS exchange webservice to achieve this.
If it is a website with a no. of users u will need to create OU in exchange server and add a admin user who has read permissions to all accounts in the DL.
EWS exposes endpoints where in u can fetch the calendar mail add read and do all kind of operations.

Answer 5

Building off Rahul's idea but using a different approach - Microsoft provides something similar to a "RSS feed" that auto updates each time you GET the URL, except it's an feed of "ICS" event data:
Open up Outlook Web Access (OWA), e.g. if you are using a microsoft.com account the URL might be https://outlook.live.com/calendar/ (if you are using some other Microsoft 365 account the URL may be different)
On the top right, click the Settings icon
Click View all Outlook Settings
Click Calendar > Shared Calendars > and under Publish a calendar, select the calendar, then under Select permissions, choose as appropriate, then click Publish
It will give you HTML and ICS links. Copy the ICS link URL.
Use your favourite programming language/tool/software to periodically do a HTTPS request (using CURL or AJAX or some other HTTP fetch) using GET method to the URL you got in step 5. You will get back a bunch of calendar data in ICS format. Use this however you need. You may be able to find some pre-written code from elsewhere that parses ICS data for you, or you can manually create your own parser code if you have to.