|By Jeff Peters||
|June 28, 2002 12:00 AM EDT||
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.
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.
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.
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...
Apr. 19, 2015 06:30 AM EDT Reads: 2,184
SYS-CON Events announced today that On the Avenue Marketing Group, a sales and marketing firm that utilizes events to market and sell products to consumers, 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. On the Avenue Marketing Group (OTA) is a sales and marketing firm that utilizes events to market and sell products to consumers. On behalf of our clients, we attend thousands of fairs, festivals, expos, concerts, conferences, and sporting events annually, helping them reach millions of individuals ...
Apr. 19, 2015 06:30 AM EDT Reads: 3,151
SYS-CON Events announced today that ActiveState, the leading independent Cloud Foundry and Docker-based PaaS provider, has been named “Silver Sponsor” of SYS-CON's DevOps Summit New York, which will take place June 9-11, 2015, at the Javits Center in New York City, NY. ActiveState believes that enterprises gain a competitive advantage when they are able to quickly create, deploy and efficiently manage software solutions that immediately create business value, but they face many challenges that prevent them from doing so. The Company is uniquely positioned to help address these challenges thro...
Apr. 19, 2015 06:15 AM EDT Reads: 2,750
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.
Apr. 19, 2015 06:00 AM EDT Reads: 2,431
SYS-CON Events announced today that Alert Logic, the leading provider of Security-as-a-Service solutions for the cloud, has been named “Bronze Sponsor” of SYS-CON's 16th International Cloud Expo® and DevOps Summit 2015 New York, which will take place June 9-11, 2015, at the Javits Center in New York City, NY, and the 17th International Cloud Expo® and DevOps Summit 2015 Silicon Valley, which will take place November 3–5, 2015, at the Santa Clara Convention Center in Santa Clara, CA.
Apr. 19, 2015 05:45 AM EDT Reads: 1,771
SYS-CON Events announced today that Akana, formerly SOA Software, has been named “Bronze Sponsor” of SYS-CON's 16th International Cloud Expo® New York, which will take place June 9-11, 2015, at the Javits Center in New York City, NY. Akana’s comprehensive suite of API Management, API Security, Integrated SOA Governance, and Cloud Integration solutions helps businesses accelerate digital transformation by securely extending their reach across multiple channels – mobile, cloud and Internet of Things. Akana enables enterprises to share data as APIs, connect and integrate applications, drive part...
Apr. 19, 2015 05:00 AM EDT Reads: 1,808
SYS-CON Events announced today that CommVault has been named “Bronze 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 City, NY, and the 17th International Cloud Expo®, which will take place on November 3–5, 2015, at the Santa Clara Convention Center in Santa Clara, CA. A singular vision – a belief in a better way to address current and future data management needs – guides CommVault in the development of Singular Information Management® solutions for high-performance data protection, universal availability and sim...
Apr. 19, 2015 04:45 AM EDT Reads: 1,745
SYS-CON Events announced today that SafeLogic has been named “Bag Sponsor” of SYS-CON's 16th International Cloud Expo® New York, which will take place June 9-11, 2015, at the Javits Center in New York City, NY. SafeLogic provides security products for applications in mobile and server/appliance environments. SafeLogic’s flagship product CryptoComply is a FIPS 140-2 validated cryptographic engine designed to secure data on servers, workstations, appliances, mobile devices, and in the Cloud.
Apr. 19, 2015 04:30 AM EDT Reads: 1,857
SYS-CON Events announced today that StorPool Storage 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. StorPool is distributed storage software that allows service providers, enterprises and other cloud builders to run data storage on standard x86 servers, instead of using expensive and inefficient storage arrays (SAN).
Apr. 19, 2015 04:00 AM EDT Reads: 1,984
SYS-CON Events announced today that Site24x7, the cloud infrastructure monitoring service, 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. Site24x7 is a cloud infrastructure monitoring service that helps monitor the uptime and performance of websites, online applications, servers, mobile websites and custom APIs. The monitoring is done from 50+ locations across the world and from various wireless carriers, thus providing a global perspective of the end-user experience. Site24x7 supports monitoring H...
Apr. 19, 2015 02:30 AM EDT Reads: 1,829
SYS-CON Events announced today that Intelligent Systems Services 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. Established in 1994, Intelligent Systems Services Inc. is located near Washington, DC, with representatives and partners nationwide. ISS’s well-established track record is based on the continuous pursuit of excellence in designing, implementing and supporting nationwide clients’ mission-critical systems. ISS has completed many successful projects in Healthcare, Commercial, Manufacturing, ...
Apr. 19, 2015 02:15 AM EDT Reads: 2,393
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...
Apr. 19, 2015 02:00 AM EDT Reads: 1,004
SYS-CON Events announced today that B2Cloud, a provider of enterprise resource planning software, 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. B2cloud develops the software you need. They have the ideal tools to help you work with your clients. B2Cloud’s main solutions include AGIS – ERP, CLOHC, AGIS – Invoice, and IZUM
Apr. 19, 2015 02:00 AM EDT Reads: 3,157
SYS-CON Events announced today that Tufin, the market-leading provider of Security Policy Orchestration Solutions, 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. As the market leader of Security Policy Orchestration, Tufin automates and accelerates network configuration changes while maintaining security and compliance. Tufin's award-winning Orchestration Suite™ gives IT organizations the power and agility to enforce security policy across complex, multi-vendor enterprise networks. With more than 1...
Apr. 19, 2015 01:45 AM EDT Reads: 3,310
VoxImplant has announced full WebRTC support in the newest versions of its Android SDK and iOS SDK. The updated SDKs, which enable audio and video calls on mobile devices, are now compatible with the WebRTC standard to allow any mobile app to communicate with WebRTC-enabled browsers, including Google Chrome, Mozilla Firefox, Opera, and, when available, Microsoft Spartan. The WebRTC-updated SDKs represent VoxImplant's continued leadership in simplifying the development of real-time communications (RTC) services for app developers. VoxImplant (built by Zingaya, the real-time communication servi...
Apr. 19, 2015 01:45 AM EDT Reads: 1,824
SYS-CON Events announced today that kintone has been named “Bronze 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 City, NY, and the 17th International Cloud Expo®, which will take place on November 3–5, 2015, at the Santa Clara Convention Center in Santa Clara, CA. kintone promotes cloud-based workgroup productivity, transparency and profitability with a seamless collaboration space, build your own business application (BYOA) platform, and workflow automation system.
Apr. 19, 2015 01:00 AM EDT Reads: 1,502
SYS-CON Events announced today that Cloudian, Inc., the leading provider of hybrid cloud storage solutions, 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. Cloudian, Inc., is a Foster City, California - based software company specializing in cloud storage software. The main product is Cloudian, an Amazon S3-compliant cloud object storage platform, the bedrock of cloud computing systems, that enables cloud service providers and enterprises to build reliable, affordable and scalable cloud storage solu...
Apr. 19, 2015 01:00 AM EDT Reads: 2,386
SYS-CON Events announced today that Gridstore™, the leader in hyper-converged infrastructure purpose-built to optimize Microsoft workloads, 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. Gridstore™ is the leader in hyper-converged infrastructure purpose-built for Microsoft workloads and designed to accelerate applications in virtualized environments. Gridstore’s hyper-converged infrastructure is the industry’s first all flash version of HyperConverged Appliances that include both compute and storag...
Apr. 19, 2015 12:45 AM EDT Reads: 4,261
SYS-CON Events announced today that IDenticard 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. IDenticard™ is the security division of Brady Corp (NYSE: BRC), a $1.5 billion manufacturer of identification products. We have small-company values with the strength and stability of a major corporation. IDenticard offers local sales, support and service to our customers across the United States and Canada. Our partner network encompasses some 300 of the world's leading systems integrators and security s...
Apr. 19, 2015 12:00 AM EDT Reads: 4,941
SYS-CON Events announced today that SoftLayer, an IBM company, has been named “Gold Sponsor” of SYS-CON's 16th International Cloud Expo®, which will take place June 9-11, 2015 at the Javits Center in New York City, NY, and the 17th International Cloud Expo®, which will take place November 3–5, 2015 at the Santa Clara Convention Center in Santa Clara, CA. SoftLayer operates a global cloud infrastructure platform built for Internet scale. With a global footprint of data centers and network points of presence, SoftLayer provides infrastructure as a service to leading-edge customers ranging from ...
Apr. 18, 2015 11:30 PM EDT Reads: 2,372