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

Using Querysims to Analyze Log Files

Using Querysims to Analyze Log Files

Query simulations, or querysims, are a means of simulating returned records from a database when no database exists. This article explores a method of using the <cf_querysim> tag to create an easy approach to custom log file processing.

Querysims 101
The <cf_querysim> custom tag was developed by Hal Helms as a tool to make development of Fusebox applications less linear. The idea was to disconnect the front-end CFML development from the back-end database and query development. To do this, <cf_querysim> provides a way to generate ColdFusion recordsets without querying a database. Instead, lines of text data are converted into a recordset.

As an example, let's imagine we're building a site that needs to display a list of employees. We need to retrieve each employee's first and last names, employee identification number, department, and supervisor ID number from the database. A <cfquery> to satisfy this requirement is shown in Listing 1. All the listings in this article have Fusedoc blocks at the top to document the function of the template. More information on Fusedoc can be found at www.fusebox.org or www.halhelms.com.

Listing 2 details dspEmployees.cfm, a template that produces a table based on the data returned by qryGetEmployees.cfm.

To tie the two together, we include them in a calling template, exampleOne.cfm, shown in Listing 3. This technique separates the back-end data portion of the code from the front-end display portion, another idea used extensively in Fusebox.

The end result, produced by running exampleOne.cfm, is shown in Figure 1. This is familiar territory for most Cold-Fusion developers. The twist comes when we want to develop and test the display component of this example before the database exists. This allows us to continue development regardless of whether there's a database yet.

To accomplish this goal, we need a way to make qryGetEmployees.cfm produce output just as though the database was done. This is where the querysim custom tag comes in. Listing 4 shows a version of qryGetEmployees.cfm that creates a querysim of desired data. The first line inside the <cf_querysim> tag defines the name of the recordset that will be produced, the second line specifies field names, and the remaining lines specify the data.

When we run exampleOne.cfm using the new querysim, the output looks exactly the same as it did in Figure 1. The querysim has taken away the need for the database.

Common Uses for Querysims
As shown in the previous examples, querysims were developed to allow developers to get on with the work of creating an application's front end without having a complete database on hand. This means that the project's participants can work in parallel, reducing the calendar time required to build the application. ColdFusion coders can work on their side of the application, supported by querysims to represent live data, while database developers work independently on the back end. As query files are written, using SQL, they're put in the application in place of the querysims that stand in their stead.

Querysims can be useful in other ways as well. For example, most of us have had to build a form to be used to add and edit data. When adding a record, we need a blank form. When editing a record, we need the form to populate with data from the database. One typical solution to this problem is to create conditional logic for each input on the form, populating the input with data if a record is available, otherwise leaving the input without a value.

Querysims make this task much more manageable. We start with the idea that a form is always in edit mode. The only difference between creating a new record and editing an existing record is that, in the case of creating, we're really editing a record with all blank fields. So we create a single piece of conditional logic at the top of the form that checks to see if we're editing a record. If not, we create a recordset using <cf_querysim>. This recordset has one record with all blank fields. This way, the code that displays the record's values for editing won't throw an error for a creation action - the recordset always exists, regardless of whether we're editing an existing record or creating a new one. Listing 5 shows a simple example of this technique.

Notice that there is no conditional logic inside the form in Listing 5. All the work is done by the querysim. Regardless of whether we're creating or editing a user, we always deal with a recordset, so there's no need for cluttered conditional logic.

Parallel development and form manipulation are powerful uses of querysims, but something came up that led me to explore more ways to take advantage of them.

The Problem
Now that we've had a quick tour of querysims, I'll get into the subject problem for this article. I recently had a request to create a project status page for one of my clients. The request was to provide daily status reports on the project using a Web page.

The restrictions on creating such a page were interesting, though. The client asked that it be quick, easy, cheap, and attractive. Quick means "Don't spend much of my money putting it together," easy means "Don't spend much of my money by making it time-consuming to update," cheap means "Don't spend much of my money," and attractive means "You're not allowed to shove a plain text page at me."

For a bunch of developers, this should be an easy request. After all, everyone on my team can write HTML, so it would be an easy matter to pop up a page of HTML and let everyone edit it daily to add their progress notes. We certainly could have gone this way, but this particular client has a habit of changing his mind, particularly where layout-related things are concerned. So I fully expected him to change his mind at some point about how he wanted these daily updates presented. That, combined with my ingrained Fusebox thinking that tells me to separate data from process and presentation, led me to consider something different.

The Solution: Idea One
The approach was simply to create a query file with a querysim in it to contain the daily update log. The querysim would present the log data for a display file to render for the user. With this approach, if the presentation requirements changed, we could just change the display file. In addition, we'd be able to use the same query file as input to a variety of displays, just in case things got interesting.

The query file I worked up is shown in Listing 6. I refer to this as "Idea One" as it became the foundation for more ideas in the same vein.

Listing 7 shows the display file I used to process the log, and Figure 2 shows the log displayed in a browser, again using a calling file (ideaOne.cfm) to pull together the query and display files.

Left at this point, the solution might have been fine. However, the ways of Fusebox, once learned, aren't easily ignored. Having developers editing the log data right in the querysim definition made me a little nervous. Everyone on the project knew better than to mess around with the CFML and to simply edit the data inside the <cf_querysim> tag, but on the off chance that someone would slip a finger and accidentally delete the starting bracket on the </cf_querysim> closing tag, I decided I needed to keep the data somewhere other than embedded directly in the <cf_querysim> tag. Enter Idea Two.

The Solution: Idea Two
Probably the simplest part of the solution, Idea Two represents the true power of this approach. The idea is simple: separate the data from the <cf_querysim> tag through the use of <cfinclude>. Using this idea, the qryWorkLog.cfm file became two files. The first is qryWorkLog2.cfm, which is just qryWorkLog.cfm with a small modification to remove the data and replace it with a <cfinclude> tag. The second is WorkLog.txt, which contains the data removed from qryWorkLog.cfm. These two files are shown in Listings 8 and 9.

The end result is the same output as shown in Figure 2. Nothing has really changed about the data or how it's presented. On the back end, though, we now have a standalone text file that can be edited without fear of breaking the querysim code.

Having implemented this solution, I looked at WorkLog.txt and realized it was nothing more than a simple log file, much like those generated by Web servers. That realization led me back to some discussions from various listservs and newsgroups about Web statistics packages and parsing server logs. It occurred to me that the use of querysims represented an easy way to import a server log into a CF recordset for further processing. And so we go on to The Next Idea.

The Next Idea: Server Logs to Recordsets
The records in a querysim data file are pipe-delimited. That is, each field is separated from the next by a vertical pipe (or bar) character. Most server logs simply have spaces between fields, making them problematic to parse efficiently. In order to use the querysim tag, I'd have to take one of two approaches. I could either modify the querysim tag to parse the server log, or I could modify the server log to comply with the querysim tag's requirements. Because spaces aren't particularly good delimiters to begin with, I decided on the latter approach.

Fortunately, I do most of my work on servers that run Apache, so modifying the server log was really very simple. I went into the Apache configuration file, httpd.conf, and added the following line along with the other LogFormat lines:

LogFormat "%h|%l|%u|%t|\"%r\"|%>s|%b" pipedcommon

This defines a new log format called "pipedcommon", which is identical to the common server log format except that it uses pipes instead of spaces between fields. I then modified the CustomLog directive to use this new log format:

CustomLog logs/access.log pipedcommon

A quick restart of Apache and it was ready to go. Every request to the server causes a line to be written to the access log, so I made a few page requests to add lines to a new log file, creating the file in Listing 10.

Then I took a copy of the log file over to my ColdFusion test directory, where I had a new file waiting for it. This file, qryWebLog.cfm, is shown in Listing 11. It's identical in concept to the qryWorkLog2.cfm file seen in Listing 8, but the querysim has a different name and the field headings are altered to match the format of the server's access log. In addition, I've added a <cfdump> tag to the end of the file to quickly show that the server log has indeed been processed into a recordset.

For live use I created a display file (dspWebLog.cfm) and a calling file (nextIdea.cfm), similar to the examples shown earlier, to create an attractive display of the access log's data. These files are shown in Listings 12 and 13, and the output from running nextIdea.cfm is shown in Figure 3.

As you can see, the Web log is neatly displayed in the browser window, in just the format I specified. This is the launching point for whatever sort of log analysis you might wish to perform. Particularly with ColdFusion's query-of-query capability, you could do just about any sort of analysis you might want on this recordset.

Other Applications for Querysims
As you think about querysims, of course, more and more uses for them become apparent. You can take advantage of <cf_querysim> any time you might want to convert text data into a recordset without worrying about a custom parser.

For example, you might want to create a bulk loader for text data. With <cf_querysim> loading the data into a recordset for you, loading the data into a database becomes a simple matter of looping over the recordset with a <cfquery> to insert the data. No doubt your imagination will be able to come up with its own uses for this extraordinarily useful custom tag.

More Stories By Jeff Peters

Jeff Peters works for Open Source Data Integration Software company XAware.

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
Enterprises have taken advantage of IoT to achieve important revenue and cost advantages. What is less apparent is how incumbent enterprises operating at scale have, following success with IoT, built analytic, operations management and software development capabilities - ranging from autonomous vehicles to manageable robotics installations. They have embraced these capabilities as if they were Silicon Valley startups.
The standardization of container runtimes and images has sparked the creation of an almost overwhelming number of new open source projects that build on and otherwise work with these specifications. Of course, there's Kubernetes, which orchestrates and manages collections of containers. It was one of the first and best-known examples of projects that make containers truly useful for production use. However, more recently, the container ecosystem has truly exploded. A service mesh like Istio addr...
Predicting the future has never been more challenging - not because of the lack of data but because of the flood of ungoverned and risk laden information. Microsoft states that 2.5 exabytes of data are created every day. Expectations and reliance on data are being pushed to the limits, as demands around hybrid options continue to grow.
Poor data quality and analytics drive down business value. In fact, Gartner estimated that the average financial impact of poor data quality on organizations is $9.7 million per year. But bad data is much more than a cost center. By eroding trust in information, analytics and the business decisions based on these, it is a serious impediment to digital transformation.
Business professionals no longer wonder if they'll migrate to the cloud; it's now a matter of when. The cloud environment has proved to be a major force in transitioning to an agile business model that enables quick decisions and fast implementation that solidify customer relationships. And when the cloud is combined with the power of cognitive computing, it drives innovation and transformation that achieves astounding competitive advantage.
Digital Transformation: Preparing Cloud & IoT Security for the Age of Artificial Intelligence. As automation and artificial intelligence (AI) power solution development and delivery, many businesses need to build backend cloud capabilities. Well-poised organizations, marketing smart devices with AI and BlockChain capabilities prepare to refine compliance and regulatory capabilities in 2018. Volumes of health, financial, technical and privacy data, along with tightening compliance requirements by...
As IoT continues to increase momentum, so does the associated risk. Secure Device Lifecycle Management (DLM) is ranked as one of the most important technology areas of IoT. Driving this trend is the realization that secure support for IoT devices provides companies the ability to deliver high-quality, reliable, secure offerings faster, create new revenue streams, and reduce support costs, all while building a competitive advantage in their markets. In this session, we will use customer use cases...
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 settlement products to hedge funds and investment banks. After, he co-founded a revenue cycle management company where he learned about Bitcoin and eventually Ethereal. Andrew's role at ConsenSys Enterprise is a mul...
DXWorldEXPO LLC announced today that "Miami Blockchain Event by FinTechEXPO" has announced that its Call for Papers is now open. The two-day event will present 20 top Blockchain experts. All speaking inquiries which covers the following information can be submitted by email to [email protected] Financial enterprises in New York City, London, Singapore, and other world financial capitals are embracing a new generation of smart, automated FinTech that eliminates many cumbersome, slow, and expe...
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.
The best way to leverage your Cloud Expo presence as a sponsor and exhibitor is to plan your news announcements around our events. The press covering Cloud Expo and @ThingsExpo will have access to these releases and will amplify your news announcements. More than two dozen Cloud companies either set deals at our shows or have announced their mergers and acquisitions at Cloud Expo. Product announcements during our show provide your company with the most reach through our targeted audiences.
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...
With 10 simultaneous tracks, keynotes, general sessions and targeted breakout classes, @CloudEXPO and DXWorldEXPO are two of the most important technology events of the year. Since its launch over eight years ago, @CloudEXPO and DXWorldEXPO have presented a rock star faculty as well as showcased hundreds of sponsors and exhibitors! In this blog post, we provide 7 tips on how, as part of our world-class faculty, you can deliver one of the most popular sessions at our events. But before reading...
Cloud Expo | DXWorld Expo have announced the conference tracks for Cloud Expo 2018. Cloud Expo will be held June 5-7, 2018, at the Javits Center in New York City, and November 6-8, 2018, at the Santa Clara Convention Center, Santa Clara, CA. Digital Transformation (DX) is a major focus with the introduction of DX Expo 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 ov...
DXWordEXPO New York 2018, colocated with CloudEXPO 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.
DXWorldEXPO LLC announced today that ICOHOLDER named "Media Sponsor" of Miami Blockchain Event by FinTechEXPO. ICOHOLDER give you detailed information and help the community to invest in the trusty projects. Miami Blockchain Event by FinTechEXPO has opened its Call for Papers. The two-day event will present 20 top Blockchain experts. All speaking inquiries which covers the following information can be submitted by email to [email protected] Miami Blockchain Event by FinTechEXPO also offers s...
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.
Digital Transformation and Disruption, Amazon Style - What You Can Learn. Chris Kocher is a co-founder of Grey Heron, a management and strategic marketing consulting firm. He has 25+ years in both strategic and hands-on operating experience helping executives and investors build revenues and shareholder value. He has consulted with over 130 companies on innovating with new business models, product strategies and monetization. Chris has held management positions at HP and Symantec in addition to ...
Cloud-enabled transformation has evolved from cost saving measure to business innovation strategy -- one that combines the cloud with cognitive capabilities to drive market disruption. Learn how you can achieve the insight and agility you need to gain a competitive advantage. Industry-acclaimed CTO and cloud expert, Shankar Kalyana presents. Only the most exceptional IBMers are appointed with the rare distinction of IBM Fellow, the highest technical honor in the company. Shankar has also receive...
With tough new regulations coming to Europe on data privacy in May 2018, Calligo will explain why in reality the effect is global and transforms how you consider critical data. EU GDPR fundamentally rewrites the rules for cloud, Big Data and IoT. In his session at 21st Cloud Expo, Adam Ryan, Vice President and General Manager EMEA at Calligo, examined the regulations and provided insight on how it affects technology, challenges the established rules and will usher in new levels of diligence arou...