Click here to close now.

Welcome!

You will be redirected in 30 seconds or close now.

ColdFusion Authors: Yakov Fain, Maureen O'Gara, Nancy Y. Nee, Tad Anderson, Daniel Kaar

Related Topics: ColdFusion

ColdFusion: Article

Creating a Remember Me Login

Implementing a login script on your site

Many of my articles in this column have dealt with theoretical concepts and syntax of implementing those concepts in ColdFusion. In this article, I want to concentrate on the implementation steps you might take when building something.

Most Web applications have a "sign me up" feature that allows users to register. Registered users often have access to additional information or features that anonymous users don't. I'm going to walk you through the process of creating a simple login form, including database authentication and a "remember me" checkbox.

The Database
Before you start coding this application, you'll need to create a database. Most login schemes include a username and password. You can put that information in a table called Users. The table will also need a unique identifier, called a primary key in database terms. Here is a sample of data from the table:

UserIDUsernamePassword
1 Jeff Houser
2 CFDJ Author
3 ColdFusion Macromedia

Normally, a users table would have much more information than just a username and password. A name, address, and e-mail address are common additions. For the purposes of this example, we'll keep it simple. In a real-world application, you should consider encrypting the passwords in your database for security purposes. You can do this using ColdFusion's hash function. More information about the hash function is located at Click Here. You would use the hash function before saving the user's password into the database. For the purposes of this example, the passwords will remain in plain text.

You could implement a login script using just the users table we defined, but you'll find it limiting. The user is either logged in, or not logged in. There is no distinction between different levels of access. Suppose, for example, that anonymous users can look at products, registered users can post reviews of products, and admin users can change product information. You'll need something more than an "Authenticated" or "Not Authenticated" security structure. To do this we'll need to be able to group users into security groups. The SecurityGroups table will need a primary key and a group name. This is an example of some possible groups:

GroupIDGroupName
1 Admin
2 Anonymous
3 Registered

You'll also need an intersection or linking table to associate a user with his or her groups. This table will contain the GroupID and the UserID. The reason for creating this as a separate table is so that a single user can be in multiple groups, and a single group can have multiple users inside of it. This is known as a many-to-many relationship in the world of database design.

Here is an example of the SecurityUserGroups intersection table:

GroupIDUserID
1 (Admin) 1 (Jeff / Houser)
3 (Registered) 1 (Jeff / Houser)
3 (Registered) 3 (ColdFusion / Macromedia)

I added the group and user names next to the ID in parentheses to more easily show the relations. In a relational database, you would store only the ID. Our finished database structure is seen in Figure 1.

Before accessing this database from your ColdFusion code, you'll have to create a datasource in the ColdFusion administrator. Setting up the datasource is beyond the scope of this article, but it's a pretty straightforward task and you can read about setting up datasources for any database at Click Here.

The Login Form
With our database ready for use, we can start examining the login form. Most forms have two parts: an input page and a processing page. The input page asks for the username and password. It also has a checkbox for a "Remember Me" functionality. The code behind the form is shown in Listing 1.

The login form can be seen here: (Figure 2)

Enter Jeff in the username field and Houser in the password field. Check the Remember Me box and click submit. This brings us to the processing page (see Listing 2).

The RememberMe form variable value comes from a checkbox. If not checked when the form is submitted, the variable will not exist on the form processing page. You can use the cfparam tag to default if this situation occurs. The second step in the process is to validate the user's login information against the database. The cfquery tag is used to run the database query. The query joins the users table and the SecurityUserGroups table, where the username and password fields are equal to the input of the form. The query retrieves all information from the users table and the list of GroupIDs from the intersection table. If the database stored hashed passwords, we would change the query comparison to:

Users.password = '#hash(form.password)#'

This allows us to correctly compare two hashed values, not plain text passwords. This way we are keeping the user's password information secure.

We can check the RecordCount variable of our query to see if the query returned any rows. If the query did not return any rows, then the user did not enter a valid username and password combination. The login should fail. If rows are returned, then the login was a success. The code creates two session variables to process the login. To make use of session variables, you'll have to use the cfapplication tag. ColdFusion's application framework is beyond the scope of this article; however, you can read about it at Click Here.

The first value, LoggedIn, is a Boolean value that specifies that the user has logged in. I would default this value to false when the session is initialized. The second variable, groups, contains a list of all the groups that the user is in. The ValueList will give us a list from the column in the query.

Later in your application, when you have to decide whether a user should have access to a resource or not, you can use ListFind against the groups variable to see if the user is allowed. Here's an example:

 


<cfif ListFind(session.Groups, 1)>
 allow Access
<cfelse>
 No Access
</cfif>

If the user is in the admin group he or she can see the resulting HTML code, or access the corresponding resource. If not, then he or she will not be given access.

In this code, we are rolling our own security scheme. Many applications will use this approach, due to the complexity of security functions in the pre-CFMX days. However ColdFusion MX introduced a much improved security scheme using some new tags: cflogin, cfloginuser, and cflogout. They allow you to log in a user and set up a list of roles that ColdFusion will handle internally. The roles tie in with the role attributes of functions inside a ColdFusion component. These new tags are not in wide use yet, but they are definitely worth checking out if you are building an application from the ground up (livedocs.macromedia.com/coldfusion/6.1/htmldocs/appsecu6.htm). The reason I don't use them in my development is because my biggest project of the moment is being built to run off of BlueDragon, which does not yet support the functions.

Remembering the User
The one portion of code that I haven't explained yet is the "remember me" portion, so let's look at it in detail. There are many different ways you could implement the "remember me" portion of code. In most methods, you'll set a cookie on the user's machine, and store the same value in the database. When the user returns to the site, you can check to see if the cookie exists. If it does, you can retrieve the user's information from the database based on the cookie value. Simpler systems where security is not an issue may store the user's primary key ID. More complex systems with heavier security requirements may assign a UniqueID value, created with the CreateUUID function. Some systems I've worked with will store the CFID and CFTOKEN values generated by ColdFusion and used for session management, and use those to remember the user.

For the purposes of our sample, we are going to store the user's primary key as a cookie, but remember that in applications where security is a priority, this is probably not your best move. If form.RememberMe is set to true, then we use the cfcookie tag to create a cookie on the user's browser. We name the cookie UserID. The value is set to the UserID value returned from the query. It is set to never expire.

Setting the cookie is only the first step. When a user comes to the site, something will have to be implemented to check to see if we know who they are, or not. We are going to put this code in the Application.cfm. The code in the Application.cfm will look like an abbreviated version of the code in the login-processing page (see Listing 3).

First the code checks whether the IsLoggedIn session variable is defined. If it isn't, then this is the first time a user has come to the site. Next, we check if the UserID cookie variable exists. If it does, Next we run a query to get the user data based on the UserID. If the query finds the user, the code sets the two session variables. If not, it defaults them to the value. If the cookie doesn't exist at all, it defaults the session values.

Conclusion
This article demonstrated a simple method for implementing a login script on your site. It incorporated many common security elements and used many common ColdFusion tags. The approach I took in this article is not the only approach that could be used, but it is simple yet elegant. For those who want more, you can check out the authenticationAPI included in Macromedia's DRK 7. In my next column I'll talk more in depth about ColdFusion's application framework and the cfapplication tag, including setting up the session and application scopes.

More Stories By Jeffry Houser

Jeffry is a technical entrepreneur with over 10 years of making the web work for you. Lately Jeffry has been cooped up in his cave building the first in a line of easy to use interface components for Flex Developers at www.flextras.com . He has a Computer Science degree from the days before business met the Internet and owns DotComIt, an Adobe Solutions Partner specializing in Rich Internet Applications. Jeffry is an Adobe Community Expert and produces The Flex Show, a podcast that includes expert interviews and screencast tutorials. Jeffry is also co-manager of the Hartford CT Adobe User Group, author of three ColdFusion books and over 30 articles, and has spoken at various events all over the US. In his spare time he is a musician, old school adventure game aficionado, and recording engineer. He also owns a Wii. You can read his blog at www.jeffryhouser.com, check out his podcast at www.theflexshow.com or check out his company at www.dot-com-it.com.

Comments (0)

Share your thoughts on this story.

Add your comment
You must be signed in to add a comment. Sign-in | Register

In accordance with our Comment Policy, we encourage comments that are on topic, relevant and to-the-point. We will remove comments that include profanity, personal attacks, racial slurs, threats of violence, or other inappropriate material that violates our Terms and Conditions, and will block users who make repeated violations. We ask all readers to expect diversity of opinion and to treat one another with dignity and respect.


@ThingsExpo Stories
SYS-CON Events announced today the IoT Bootcamp – Jumpstart Your IoT Strategy, being held June 9–10, 2015, in conjunction with 16th Cloud Expo and Internet of @ThingsExpo at the Javits Center in New York City. This is your chance to jumpstart your IoT strategy. Combined with real-world scenarios and use cases, the IoT Bootcamp is not just based on presentations but includes hands-on demos and walkthroughs. We will introduce you to a variety of Do-It-Yourself IoT platforms including Arduino, Raspberry Pi, BeagleBone, Spark and Intel Edison. You will also get an overview of cloud technologies s...
The best mobile applications are augmented by dedicated servers, the Internet and Cloud services. Mobile developers should focus on one thing: writing the next socially disruptive viral app. Thanks to the cloud, they can focus on the overall solution, not the underlying plumbing. From iOS to Android and Windows, developers can leverage cloud services to create a common cross-platform backend to persist user settings, app data, broadcast notifications, run jobs, etc. This session provides a high level technical overview of many cloud services available to mobile app developers, includi...
“In the past year we've seen a lot of stabilization of WebRTC. You can now use it in production with a far greater degree of certainty. A lot of the real developments in the past year have been in things like the data channel, which will enable a whole new type of application," explained Peter Dunkley, Technical Director at Acision, in this SYS-CON.tv interview at @ThingsExpo, held Nov 4–6, 2014, at the Santa Clara Convention Center in Santa Clara, CA.
Health care systems across the globe are under enormous strain, as facilities reach capacity and costs continue to rise. M2M and the Internet of Things have the potential to transform the industry through connected health solutions that can make care more efficient while reducing costs. In fact, Vodafone's annual M2M Barometer Report forecasts M2M applications rising to 57 percent in health care and life sciences by 2016. Lively is one of Vodafone's health care partners, whose solutions enable older adults to live independent lives while staying connected to loved ones. M2M will continue to gr...
SYS-CON Events announced today that Ciqada will exhibit at SYS-CON's @ThingsExpo, which will take place on June 9-11, 2015, at the Javits Center in New York City, NY. Ciqada™ makes it easy to connect your products to the Internet. By integrating key components - hardware, servers, dashboards, and mobile apps - into an easy-to-use, configurable system, your products can quickly and securely join the internet of things. With remote monitoring, control, and alert messaging capability, you will meet your customers' needs of tomorrow - today! Ciqada. Let your products take flight. For more inform...
Containers and microservices have become topics of intense interest throughout the cloud developer and enterprise IT communities. Accordingly, attendees at the upcoming 16th Cloud Expo at the Javits Center in New York June 9-11 will find fresh new content in a new track called PaaS | Containers & Microservices Containers are not being considered for the first time by the cloud community, but a current era of re-consideration has pushed them to the top of the cloud agenda. With the launch of Docker's initial release in March of 2013, interest was revved up several notches. Then late last...
Dave will share his insights on how Internet of Things for Enterprises are transforming and making more productive and efficient operations and maintenance (O&M) procedures in the cleantech industry and beyond. Speaker Bio: Dave Landa is chief operating officer of Cybozu Corp (kintone US). Based in the San Francisco Bay Area, Dave has been on the forefront of the Cloud revolution driving strategic business development on the executive teams of multiple leading Software as a Services (SaaS) application providers dating back to 2004. Cybozu's kintone.com is a leading global BYOA (Build Your O...
While not quite mainstream yet, WebRTC is starting to gain ground with Carriers, Enterprises and Independent Software Vendors (ISV’s) alike. WebRTC makes it easy for developers to add audio and video communications into their applications by using Web browsers as their platform. But like any market, every customer engagement has unique requirements, as well as constraints. And of course, one size does not fit all. In her session at WebRTC Summit, Dr. Natasha Tamaskar, Vice President, Head of Cloud and Mobile Strategy at GENBAND, will explore what is needed to take a real time communications ...
SYS-CON Media announced today that @WebRTCSummit Blog, the largest WebRTC resource in the world, has been launched. @WebRTCSummit Blog offers top articles, news stories, and blog posts from the world's well-known experts and guarantees better exposure for its authors than any other publication. @WebRTCSummit Blog can be bookmarked ▸ Here @WebRTCSummit conference site can be bookmarked ▸ Here
SYS-CON Events announced today that GENBAND, a leading developer of real time communications software solutions, has been named “Silver Sponsor” of SYS-CON's WebRTC Summit, which will take place on June 9-11, 2015, at the Javits Center in New York City, NY. The GENBAND team will be on hand to demonstrate their newest product, Kandy. Kandy is a communications Platform-as-a-Service (PaaS) that enables companies to seamlessly integrate more human communications into their Web and mobile applications - creating more engaging experiences for their customers and boosting collaboration and productiv...
SYS-CON Events announced today that BroadSoft, the leading global provider of Unified Communications and Collaboration (UCC) services to operators worldwide, has been named “Gold Sponsor” of SYS-CON's WebRTC Summit, which will take place on June 9-11, 2015, at the Javits Center in New York City, NY. BroadSoft is the leading provider of software and services that enable mobile, fixed-line and cable service providers to offer Unified Communications over their Internet Protocol networks. The Company’s core communications platform enables the delivery of a range of enterprise and consumer calling...
The 17th International Cloud Expo has announced that its Call for Papers is open. 17th International Cloud Expo, to be held November 3-5, 2015, at the Santa Clara Convention Center in Santa Clara, CA, brings together Cloud Computing, APM, APIs, Microservices, Security, Big Data, Internet of Things, DevOps and WebRTC to one location. With cloud computing driving a higher percentage of enterprise IT budgets every year, it becomes increasingly important to plant your flag in this fast-expanding business opportunity. Submit your speaking proposal today!
So I guess we’ve officially entered a new era of lean and mean. I say this with the announcement of Ubuntu Snappy Core, “designed for lightweight cloud container hosts running Docker and for smart devices,” according to Canonical. “Snappy Ubuntu Core is the smallest Ubuntu available, designed for security and efficiency in devices or on the cloud.” This first version of Snappy Ubuntu Core features secure app containment and Docker 1.6 (1.5 in main release), is available on public clouds, and for ARM and x86 devices on several IoT boards. It’s a Trend! This announcement comes just as...
What exactly is a cognitive application? In her session at 16th Cloud Expo, Ashley Hathaway, Product Manager at IBM Watson, will look at the services being offered by the IBM Watson Developer Cloud and what that means for developers and Big Data. She'll explore how IBM Watson and its partnerships will continue to grow and help define what it means to be a cognitive service, as well as take a look at the offerings on Bluemix. She will also check out how Watson and the Alchemy API team up to offer disruptive APIs to developers.
The IoT Bootcamp is coming to Cloud Expo | @ThingsExpo on June 9-10 at the Javits Center in New York. Instructor. Registration is now available at http://iotbootcamp.sys-con.com/ Instructor Janakiram MSV previously taught the famously successful Multi-Cloud Bootcamp at Cloud Expo | @ThingsExpo in November in Santa Clara. Now he is expanding the focus to Janakiram is the founder and CTO of Get Cloud Ready Consulting, a niche Cloud Migration and Cloud Operations firm that recently got acquired by Aditi Technologies. He is a Microsoft Regional Director for Hyderabad, India, and one of the f...
SYS-CON Events announced today that Litmus Automation will exhibit at SYS-CON's 16th International Cloud Expo®, which will take place on June 9-11, 2015, at the Javits Center in New York City, NY. Litmus Automation’s vision is to provide a solution for companies that are in a rush to embrace the disruptive Internet of Things technology and leverage it for real business challenges. Litmus Automation simplifies the complexity of connected devices applications with Loop, a secure and scalable cloud platform.
In 2015, 4.9 billion connected "things" will be in use. By 2020, Gartner forecasts this amount to be 25 billion, a 410 percent increase in just five years. How will businesses handle this rapid growth of data? Hadoop will continue to improve its technology to meet business demands, by enabling businesses to access/analyze data in real time, when and where they need it. Cloudera's Chief Technologist, Eli Collins, will discuss how Big Data is keeping up with today's data demands and how in the future, data and analytics will be pervasive, embedded into every workflow, application and infra...
As Marc Andreessen says software is eating the world. Everything is rapidly moving toward being software-defined – from our phones and cars through our washing machines to the datacenter. However, there are larger challenges when implementing software defined on a larger scale - when building software defined infrastructure. In his session at 16th Cloud Expo, Boyan Ivanov, CEO of StorPool, will provide some practical insights on what, how and why when implementing "software-defined" in the datacenter.
SYS-CON Media announced today that @ThingsExpo Blog launched with 7,788 original stories. @ThingsExpo Blog offers top articles, news stories, and blog posts from the world's well-known experts and guarantees better exposure for its authors than any other publication. @ThingsExpo Blog can be bookmarked. The Internet of Things (IoT) is the most profound change in personal and enterprise IT since the creation of the Worldwide Web more than 20 years ago.
The world's leading Cloud event, Cloud Expo has launched Microservices Journal on the SYS-CON.com portal, featuring over 19,000 original articles, news stories, features, and blog entries. DevOps Journal is focused on this critical enterprise IT topic in the world of cloud computing. Microservices Journal offers top articles, news stories, and blog posts from the world's well-known experts and guarantees better exposure for its authors than any other publication. Follow new article posts on Twitter at @MicroservicesE