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
Sensor-enabled things are becoming more commonplace, precursors to a larger and more complex framework that most consider the ultimate promise of the IoT: things connecting, interacting, sharing, storing, and over time perhaps learning and predicting based on habits, behaviors, location, preferences, purchases and more. In his session at @ThingsExpo, Tom Wesselman, Director of Communications Ecosystem Architecture at Plantronics, will examine the still nascent IoT as it is coalescing, including what it is today, what it might ultimately be, the role of wearable tech, and technology gaps stil...
The Internet of Things (IoT) is causing data centers to become radically decentralized and atomized within a new paradigm known as “fog computing.” To support IoT applications, such as connected cars and smart grids, data centers' core functions will be decentralized out to the network's edges and endpoints (aka “fogs”). As this trend takes hold, Big Data analytics platforms will focus on high-volume log analysis (aka “logs”) and rely heavily on cognitive-computing algorithms (aka “cogs”) to make sense of it all.
With several hundred implementations of IoT-enabled solutions in the past 12 months alone, this session will focus on experience over the art of the possible. Many can only imagine the most advanced telematics platform ever deployed, supporting millions of customers, producing tens of thousands events or GBs per trip, and hundreds of TBs per month. With the ability to support a billion sensor events per second, over 30PB of warm data for analytics, and hundreds of PBs for an data analytics archive, in his session at @ThingsExpo, Jim Kaskade, Vice President and General Manager, Big Data & Ana...
In the consumer IoT, everything is new, and the IT world of bits and bytes holds sway. But industrial and commercial realms encompass operational technology (OT) that has been around for 25 or 50 years. This grittier, pre-IP, more hands-on world has much to gain from Industrial IoT (IIoT) applications and principles. But adding sensors and wireless connectivity won’t work in environments that demand unwavering reliability and performance. In his session at @ThingsExpo, Ron Sege, CEO of Echelon, will discuss how as enterprise IT embraces other IoT-related technology trends, enterprises with i...
When it comes to the Internet of Things, hooking up will get you only so far. If you want customers to commit, you need to go beyond simply connecting products. You need to use the devices themselves to transform how you engage with every customer and how you manage the entire product lifecycle. In his session at @ThingsExpo, Sean Lorenz, Technical Product Manager for Xively at LogMeIn, will show how “product relationship management” can help you leverage your connected devices and the data they generate about customer usage and product performance to deliver extremely compelling and reliabl...
One of the biggest impacts of the Internet of Things is and will continue to be on data; specifically data volume, management and usage. Companies are scrambling to adapt to this new and unpredictable data reality with legacy infrastructure that cannot handle the speed and volume of data. In his session at @ThingsExpo, Don DeLoach, CEO and president of Infobright, will discuss how companies need to rethink their data infrastructure to participate in the IoT, including: Data storage: Understanding the kinds of data: structured, unstructured, big/small? Analytics: What kinds and how responsiv...
Since 2008 and for the first time in history, more than half of humans live in urban areas, urging cities to become “smart.” Today, cities can leverage the wide availability of smartphones combined with new technologies such as Beacons or NFC to connect their urban furniture and environment to create citizen-first services that improve transportation, way-finding and information delivery. In her session at @ThingsExpo, Laetitia Gazel-Anthoine, CEO of Connecthings, will focus on successful use cases.
Sensor-enabled things are becoming more commonplace, precursors to a larger and more complex framework that most consider the ultimate promise of the IoT: things connecting, interacting, sharing, storing, and over time perhaps learning and predicting based on habits, behaviors, location, preferences, purchases and more. In his session at @ThingsExpo, Tom Wesselman, Director of Communications Ecosystem Architecture at Plantronics, will examine the still nascent IoT as it is coalescing, including what it is today, what it might ultimately be, the role of wearable tech, and technology gaps stil...
The true value of the Internet of Things (IoT) lies not just in the data, but through the services that protect the data, perform the analysis and present findings in a usable way. With many IoT elements rooted in traditional IT components, Big Data and IoT isn’t just a play for enterprise. In fact, the IoT presents SMBs with the prospect of launching entirely new activities and exploring innovative areas. CompTIA research identifies several areas where IoT is expected to have the greatest impact.
Wearable devices have come of age. The primary applications of wearables so far have been "the Quantified Self" or the tracking of one's fitness and health status. We propose the evolution of wearables into social and emotional communication devices. Our BE(tm) sensor uses light to visualize the skin conductance response. Our sensors are very inexpensive and can be massively distributed to audiences or groups of any size, in order to gauge reactions to performances, video, or any kind of presentation. In her session at @ThingsExpo, Jocelyn Scheirer, CEO & Founder of Bionolux, will discuss ho...
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...
Roberto Medrano, Executive Vice President at SOA Software, had reached 30,000 page views on his home page - http://RobertoMedrano.SYS-CON.com/ - on the SYS-CON family of online magazines, which includes Cloud Computing Journal, Internet of Things Journal, Big Data Journal, and SOA World Magazine. He is a recognized executive in the information technology fields of SOA, internet security, governance, and compliance. He has extensive experience with both start-ups and large companies, having been involved at the beginning of four IT industries: EDA, Open Systems, Computer Security and now SOA.
From telemedicine to smart cars, digital homes and industrial monitoring, the explosive growth of IoT has created exciting new business opportunities for real time calls and messaging. In his session at @ThingsExpo, Ivelin Ivanov, CEO and Co-Founder of Telestax, shared some of the new revenue sources that IoT created for Restcomm – the open source telephony platform from Telestax. Ivelin Ivanov is a technology entrepreneur who founded Mobicents, an Open Source VoIP Platform, to help create, deploy, and manage applications integrating voice, video and data. He is the co-founder of TeleStax, a...
The industrial software market has treated data with the mentality of “collect everything now, worry about how to use it later.” We now find ourselves buried in data, with the pervasive connectivity of the (Industrial) Internet of Things only piling on more numbers. There’s too much data and not enough information. In his session at @ThingsExpo, Bob Gates, Global Marketing Director, GE’s Intelligent Platforms business, to discuss how realizing the power of IoT, software developers are now focused on understanding how industrial data can create intelligence for industrial operations. Imagine ...
Operational Hadoop and the Lambda Architecture for Streaming Data Apache Hadoop is emerging as a distributed platform for handling large and fast incoming streams of data. Predictive maintenance, supply chain optimization, and Internet-of-Things analysis are examples where Hadoop provides the scalable storage, processing, and analytics platform to gain meaningful insights from granular data that is typically only valuable from a large-scale, aggregate view. One architecture useful for capturing and analyzing streaming data is the Lambda Architecture, representing a model of how to analyze rea...
SYS-CON Events announced today that Vitria Technology, Inc. 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. Vitria will showcase the company’s new IoT Analytics Platform through live demonstrations at booth #330. Vitria’s IoT Analytics Platform, fully integrated and powered by an operational intelligence engine, enables customers to rapidly build and operationalize advanced analytics to deliver timely business outcomes for use cases across the industrial, enterprise, and consumer segments.
The explosion of connected devices / sensors is creating an ever-expanding set of new and valuable data. In parallel the emerging capability of Big Data technologies to store, access, analyze, and react to this data is producing changes in business models under the umbrella of the Internet of Things (IoT). In particular within the Insurance industry, IoT appears positioned to enable deep changes by altering relationships between insurers, distributors, and the insured. In his session at @ThingsExpo, Michael Sick, a Senior Manager and Big Data Architect within Ernst and Young's Financial Servi...
SYS-CON Events announced today that Open Data Centers (ODC), a carrier-neutral colocation provider, will exhibit at SYS-CON's 16th International Cloud Expo®, which will take place June 9-11, 2015, at the Javits Center in New York City, NY. Open Data Centers is a carrier-neutral data center operator in New Jersey and New York City offering alternative connectivity options for carriers, service providers and enterprise customers.
When it comes to the Internet of Things, hooking up will get you only so far. If you want customers to commit, you need to go beyond simply connecting products. You need to use the devices themselves to transform how you engage with every customer and how you manage the entire product lifecycle. In his session at @ThingsExpo, Sean Lorenz, Technical Product Manager for Xively at LogMeIn, will show how “product relationship management” can help you leverage your connected devices and the data they generate about customer usage and product performance to deliver extremely compelling and reliabl...
SYS-CON Events announced today that CodeFutures, a leading supplier of database performance tools, has been named a “Sponsor” of SYS-CON's 16th International Cloud Expo®, which will take place on June 9–11, 2015, at the Javits Center in New York, NY. CodeFutures is an independent software vendor focused on providing tools that deliver database performance tools that increase productivity during database development and increase database performance and scalability during production.