Contacting a contact list: A tutorial

Previously I have shown how it is possible to grab a visitors contact list, with their permission and login details, from Gmail, MSN messenger and AOL instant messenger (AIM). I left those scripts at the stage of having a great long list of emails you want to contact but no way yet to actually contact them. Obviously we want to send out an email to each contact but what is the best way to do this?

In this tutorial I'm only going to look at Gmail and MSN messenger contact lists because as I have posted previously I still have concerns about contacting the screen names from an AIM contact list by email. I’m going to briefly look at grabbing a contact list from both a Gmail account and an MSN messenger account. I'm then going to display these contacts back to the user so they can select which contacts they actually want to contact. Then I'm going to look at one way to send an email to all the contacts the user selects.

This whole process can be broken down into three parts: getting the login details, getting the contacts and displaying them to the user and then finally emailing those contacts the user wished to contact. The process could be reduced into just two steps if we didn't allow the user to choose which of their contacts they wanted to contact. The reason for this additional step is that most of us have more than one group of friends with whom we share different passions. Your user probably will not wish to let the friends they met at last month's heavy metal concert know about a great new Spanish wine they discovered last night. The same could be said about the friends they met at the wine society and the dates of an upcoming concert they are looking forward to. The more control your visitors feel they have the more likely they are to actually use the system.

Ok, that's enough discussion for now. Let's look at some actual code. The first stage is to get the users login details.

get_login_details.php


This first script is fairly basic, just a simple html form and some text to explain to the user what is going on.

The second script takes the login details from the first script and actually fetches the user’s contacts.

choose_contacts.php


Different things have to happen for MSN messenger and Gmail so on line 8 we have an ‘if’ statement to check which type of contact list we are going to fetch. After this the contact list for MSN messenger and Gmail can be fetched in a few lines of code. I’ve already covered exactly what is going on in previous posts so I will not go into detail here. The end result however is that we have an array, ‘returned_emails’, that contains all the contacts.

The list of emails is converted into a table as part of a form. At present all emails are checked so will be passed to the send email script unless unselected by the user.

I’m going to keep the sending emails step simple and use the PHP mail function. This is fine for basic text emails but you might want to look at alternative solutions (phpmailer or one of the myriad other email sending classes available) to send more complex emails, using html and embedded images for example.

send_emails.php


This third page is relatively simple, the list of emails we want to contact are returned in the $_POST array. I simply cycle through the array and send an email to each email present.

So there you have it, a simple step-by-step guide to contacting an entire contacts list. I hope you find it useful.

The whole tool can be tried out here (no actual emails are sent) and the files discussed above can be downloaded here. The class for interacting with the MSN service can be downloaded from this post and instructions on getting the gmail library are available here.