Welcome!

You will be redirected in 30 seconds or close now.

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

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
Identity is in everything and customers are looking to their providers to ensure the security of their identities, transactions and data. With the increased reliance on cloud-based services, service providers must build security and trust into their offerings, adding value to customers and improving the user experience. Making identity, security and privacy easy for customers provides a unique advantage over the competition.
SYS-CON Events announced today that Commvault, a global leader in enterprise data protection and information management, has been named “Bronze Sponsor” of SYS-CON's 19th International Cloud Expo, which will take place on November 1–3, 2016, at the Santa Clara Convention Center in Santa Clara, CA. Commvault is a leading provider of data protection and information management solutions, helping companies worldwide activate their data to drive more value and business insight and to transform moder...
SYS-CON Events has announced today that Roger Strukhoff has been named conference chair of Cloud Expo and @ThingsExpo 2016 Silicon Valley. The 19th Cloud Expo and 6th @ThingsExpo will take place on November 1-3, 2016, at the Santa Clara Convention Center in Santa Clara, CA. "The Internet of Things brings trillions of dollars of opportunity to developers and enterprise IT, no matter how you measure it," stated Roger Strukhoff. "More importantly, it leverages the power of devices and the Interne...
Personalization has long been the holy grail of marketing. Simply stated, communicate the most relevant offer to the right person and you will increase sales. To achieve this, you must understand the individual. Consequently, digital marketers developed many ways to gather and leverage customer information to deliver targeted experiences. In his session at @ThingsExpo, Lou Casal, Founder and Principal Consultant at Practicala, discussed how the Internet of Things (IoT) has accelerated our abil...
Digital innovation is the next big wave of business transformation based on digital technologies of which IoT and Big Data are key components, For example: Business boundary innovation is a challenge to excavate third-party business value using IoT and BigData, like Nest Business structure innovation may propose re-building business structure from scratch, as Uber does in the taxicab industry The social model innovation is also a big challenge to the new social architecture with the design fr...
So, you bought into the current machine learning craze and went on to collect millions/billions of records from this promising new data source. Now, what do you do with them? Too often, the abundance of data quickly turns into an abundance of problems. How do you extract that "magic essence" from your data without falling into the common pitfalls? In her session at @ThingsExpo, Natalia Ponomareva, Software Engineer at Google, provided tips on how to be successful in large scale machine learning...
If you had a chance to enter on the ground level of the largest e-commerce market in the world – would you? China is the world’s most populated country with the second largest economy and the world’s fastest growing market. It is estimated that by 2018 the Chinese market will be reaching over $30 billion in gaming revenue alone. Admittedly for a foreign company, doing business in China can be challenging. Often changing laws, administrative regulations and the often inscrutable Chinese Interne...
Why do your mobile transformations need to happen today? Mobile is the strategy that enterprise transformation centers on to drive customer engagement. In his general session at @ThingsExpo, Roger Woods, Director, Mobile Product & Strategy – Adobe Marketing Cloud, covered key IoT and mobile trends that are forcing mobile transformation, key components of a solid mobile strategy and explored how brands are effectively driving mobile change throughout the enterprise.
In his session at @ThingsExpo, Kausik Sridharabalan, founder and CTO of Pulzze Systems, Inc., will focus on key challenges in building an Internet of Things solution infrastructure. He will shed light on efficient ways of defining interactions within IoT solutions, leading to cost and time reduction. He will also introduce ways to handle data and how one can develop IoT solutions that are lean, flexible and configurable, thus making IoT infrastructure agile and scalable.
Data is an unusual currency; it is not restricted by the same transactional limitations as money or people. In fact, the more that you leverage your data across multiple business use cases, the more valuable it becomes to the organization. And the same can be said about the organization’s analytics. In his session at 19th Cloud Expo, Bill Schmarzo, CTO for the Big Data Practice at EMC, will introduce a methodology for capturing, enriching and sharing data (and analytics) across the organizati...
Internet of @ThingsExpo has announced today that Chris Matthieu has been named tech chair of Internet of @ThingsExpo 2016 Silicon Valley. The 6thInternet of @ThingsExpo will take place on November 1–3, 2016, at the Santa Clara Convention Center in Santa Clara, CA.
SYS-CON Events announced today that Bsquare has been named “Silver Sponsor” of SYS-CON's @ThingsExpo, which will take place on November 1–3, 2016, at the Santa Clara Convention Center in Santa Clara, CA. For more than two decades, Bsquare has helped its customers extract business value from a broad array of physical assets by making them intelligent, connecting them, and using the data they generate to optimize business processes.
A strange thing is happening along the way to the Internet of Things, namely far too many devices to work with and manage. It has become clear that we'll need much higher efficiency user experiences that can allow us to more easily and scalably work with the thousands of devices that will soon be in each of our lives. Enter the conversational interface revolution, combining bots we can literally talk with, gesture to, and even direct with our thoughts, with embedded artificial intelligence, wh...
Video experiences should be unique and exciting! But that doesn’t mean you need to patch all the pieces yourself. Users demand rich and engaging experiences and new ways to connect with you. But creating robust video applications at scale can be complicated, time-consuming and expensive. In his session at @ThingsExpo, Zohar Babin, Vice President of Platform, Ecosystem and Community at Kaltura, will discuss how VPaaS enables you to move fast, creating scalable video experiences that reach your...
In his keynote at 18th Cloud Expo, Andrew Keys, Co-Founder of ConsenSys Enterprise, provided an overview of the evolution of the Internet and the Database and the future of their combination – the Blockchain. Andrew Keys is Co-Founder of ConsenSys Enterprise. He comes to ConsenSys Enterprise with capital markets, technology and entrepreneurial experience. Previously, he worked for UBS investment bank in equities analysis. Later, he was responsible for the creation and distribution of life sett...
Cloud computing is being adopted in one form or another by 94% of enterprises today. Tens of billions of new devices are being connected to The Internet of Things. And Big Data is driving this bus. An exponential increase is expected in the amount of information being processed, managed, analyzed, and acted upon by enterprise IT. This amazing is not part of some distant future - it is happening today. One report shows a 650% increase in enterprise data by 2020. Other estimates are even higher....
SYS-CON Events announced today that SoftLayer, an IBM Company, has been named “Gold Sponsor” of SYS-CON's 18th Cloud Expo, which will take place on June 7-9, 2016, at the Javits Center in New York, New York. SoftLayer, an IBM Company, provides cloud infrastructure as a service from a growing number of data centers and network points of presence around the world. SoftLayer’s customers range from Web startups to global enterprises.
19th Cloud Expo, taking place November 1-3, 2016, at the Santa Clara Convention Center in Santa Clara, CA, will feature technical sessions from a rock star conference faculty and the leading industry players in the world. Cloud computing is now being embraced by a majority of enterprises of all sizes. Yesterday's debate about public vs. private has transformed into the reality of hybrid cloud: a recent survey shows that 74% of enterprises have a hybrid cloud strategy. Meanwhile, 94% of enterpri...
Businesses are struggling to manage the information flow and interactions between all of these new devices and things jumping on their network, and the apps and IT systems they control. The data businesses gather is only helpful if they can do something with it. In his session at @ThingsExpo, Chris Witeck, Principal Technology Strategist at Citrix, will discuss how different the impact of IoT will be for large businesses, expanding how IoT will allow large organizations to make their legacy ap...
In his general session at 18th Cloud Expo, Lee Atchison, Principal Cloud Architect and Advocate at New Relic, discussed cloud as a ‘better data center’ and how it adds new capacity (faster) and improves application availability (redundancy). The cloud is a ‘Dynamic Tool for Dynamic Apps’ and resource allocation is an integral part of your application architecture, so use only the resources you need and allocate /de-allocate resources on the fly.