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
In his keynote at 19th Cloud Expo, Sheng Liang, co-founder and CEO of Rancher Labs, discussed the technological advances and new business opportunities created by the rapid adoption of containers. With the success of Amazon Web Services (AWS) and various open source technologies used to build private clouds, cloud computing has become an essential component of IT strategy. However, users continue to face challenges in implementing clouds, as older technologies evolve and newer ones like Docker c...
"MobiDev is a software development company and we do complex, custom software development for everybody from entrepreneurs to large enterprises," explained Alan Winters, U.S. Head of Business Development at MobiDev, in this SYS-CON.tv interview at 21st Cloud Expo, held Oct 31 – Nov 2, 2017, at the Santa Clara Convention Center in Santa Clara, CA.
22nd International Cloud Expo, taking place June 5-7, 2018, at the Javits Center in New York City, NY, and co-located with the 1st DXWorld Expo 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 ...
@DevOpsSummit at Cloud Expo, taking place November 12-13 in New York City, NY, is co-located with 22nd international CloudEXPO | first international DXWorldEXPO and will feature technical sessions from a rock star conference faculty and the leading industry players in the world.
JETRO showcased Japan Digital Transformation Pavilion at SYS-CON's 21st International Cloud Expo® at the Santa Clara Convention Center in Santa Clara, CA. The Japan External Trade Organization (JETRO) is a non-profit organization that provides business support services to companies expanding to Japan. With the support of JETRO's dedicated staff, clients can incorporate their business; receive visa, immigration, and HR support; find dedicated office space; identify local government subsidies; get...
Dion Hinchcliffe is an internationally recognized digital expert, bestselling book author, frequent keynote speaker, analyst, futurist, and transformation expert based in Washington, DC. He is currently Chief Strategy Officer at the industry-leading digital strategy and online community solutions firm, 7Summits.
Bill Schmarzo, author of "Big Data: Understanding How Data Powers Big Business" and "Big Data MBA: Driving Business Strategies with Data Science," is responsible for setting the strategy and defining the Big Data service offerings and capabilities for EMC Global Services Big Data Practice. As the CTO for the Big Data Practice, he is responsible for working with organizations to help them identify where and how to start their big data journeys. He's written several white papers, is an avid blogge...
In past @ThingsExpo presentations, Joseph di Paolantonio has explored how various Internet of Things (IoT) and data management and analytics (DMA) solution spaces will come together as sensor analytics ecosystems. This year, in his session at @ThingsExpo, Joseph di Paolantonio from DataArchon, added the numerous Transportation areas, from autonomous vehicles to “Uber for containers.” While IoT data in any one area of Transportation will have a huge impact in that area, combining sensor analytic...
Bill Schmarzo, author of "Big Data: Understanding How Data Powers Big Business" and "Big Data MBA: Driving Business Strategies with Data Science," is responsible for setting the strategy and defining the Big Data service offerings and capabilities for EMC Global Services Big Data Practice. As the CTO for the Big Data Practice, he is responsible for working with organizations to help them identify where and how to start their big data journeys. He's written several white papers, is an avid blogge...
Charles Araujo is an industry analyst, internationally recognized authority on the Digital Enterprise and author of The Quantum Age of IT: Why Everything You Know About IT is About to Change. As Principal Analyst with Intellyx, he writes, speaks and advises organizations on how to navigate through this time of disruption. He is also the founder of The Institute for Digital Transformation and a sought after keynote speaker. He has been a regular contributor to both InformationWeek and CIO Insight...
Michael Maximilien, better known as max or Dr. Max, is a computer scientist with IBM. At IBM Research Triangle Park, he was a principal engineer for the worldwide industry point-of-sale standard: JavaPOS. At IBM Research, some highlights include pioneering research on semantic Web services, mashups, and cloud computing, and platform-as-a-service. He joined the IBM Cloud Labs in 2014 and works closely with Pivotal Inc., to help make the Cloud Found the best PaaS.
It is of utmost importance for the future success of WebRTC to ensure that interoperability is operational between web browsers and any WebRTC-compliant client. To be guaranteed as operational and effective, interoperability must be tested extensively by establishing WebRTC data and media connections between different web browsers running on different devices and operating systems. In his session at WebRTC Summit at @ThingsExpo, Dr. Alex Gouaillard, CEO and Founder of CoSMo Software, presented ...
I think DevOps is now a rambunctious teenager - it's starting to get a mind of its own, wanting to get its own things but it still needs some adult supervision," explained Thomas Hooker, VP of marketing at CollabNet, in this SYS-CON.tv interview at DevOps Summit at 20th Cloud Expo, held June 6-8, 2017, at the Javits Center in New York City, NY.
CloudEXPO New York 2018, colocated with DXWorldEXPO New York 2018 will be held November 11-13, 2018, in New York City and will bring together Cloud Computing, FinTech and Blockchain, Digital Transformation, Big Data, Internet of Things, DevOps, AI, Machine Learning and WebRTC to one location.
DevOpsSummit New York 2018, colocated with CloudEXPO | DXWorldEXPO New York 2018 will be held November 11-13, 2018, in New York City. Digital Transformation (DX) is a major focus with the introduction of DXWorldEXPO within the program. Successful transformation requires a laser focus on being data-driven and on using all the tools available that enable transformation if they plan to survive over the long term. A total of 88% of Fortune 500 companies from a generation ago are now out of bus...
Everything run by electricity will eventually be connected to the Internet. Get ahead of the Internet of Things revolution. In his session at @ThingsExpo, Akvelon expert and IoT industry leader Sergey Grebnov provided an educational dive into the world of managing your home, workplace and all the devices they contain with the power of machine-based AI and intelligent Bot services for a completely streamlined experience.
DXWorldEXPO | CloudEXPO are the world's most influential, independent events where Cloud Computing was coined and where technology buyers and vendors meet to experience and discuss the big picture of Digital Transformation and all of the strategies, tactics, and tools they need to realize their goals. Sponsors of DXWorldEXPO | CloudEXPO benefit from unmatched branding, profile building and lead generation opportunities.
In his keynote at 19th Cloud Expo, Sheng Liang, co-founder and CEO of Rancher Labs, discussed the technological advances and new business opportunities created by the rapid adoption of containers. With the success of Amazon Web Services (AWS) and various open source technologies used to build private clouds, cloud computing has become an essential component of IT strategy. However, users continue to face challenges in implementing clouds, as older technologies evolve and newer ones like Docker c...
"Evatronix provides design services to companies that need to integrate the IoT technology in their products but they don't necessarily have the expertise, knowledge and design team to do so," explained Adam Morawiec, VP of Business Development at Evatronix, in this SYS-CON.tv interview at @ThingsExpo, held Oct 31 – Nov 2, 2017, at the Santa Clara Convention Center in Santa Clara, CA.
WebRTC is great technology to build your own communication tools. It will be even more exciting experience it with advanced devices, such as a 360 Camera, 360 microphone, and a depth sensor camera. In his session at @ThingsExpo, Masashi Ganeko, a manager at INFOCOM Corporation, introduced two experimental projects from his team and what they learned from them. "Shotoku Tamago" uses the robot audition software HARK to track speakers in 360 video of a remote party. "Virtual Teleport" uses a multip...