Programming

Fixing 'Call to Undefined Function' Filter_Var() in PHP

I host a lot of websites in the Amazon cloud on EC2. I recently discovered that all email one site was sending was being rated as spam and never seen by the recipient. This meant that new users didn't get the verification email required to complete signup. It appears that EC2 IP addresses can have a dodgy reputation among email providers. Another web publisher described these problems on AWS Developer Forums. Since then I've been rewriting my code to deliver emails with SendGrid, a service ... (read more)

Working from Home? Welcome to My World

Jake Savin has a blog post up about working from home, something he began doing as a developer at UserLand Software in 2000 coding the blogging platform Manila and other products. Though it wasn't a remote position when he began the job, that soon changed: The company actually had an office when I was hired, and I had my own space with a desk and a door, a desktop computer, etc. There were only two of us in the office though, and it quickly became clear to me that the value of driving 35-40 ... (read more)

I'm a ServiceNow Certified Application Developer

I passed the ServiceNow certified application developer test today at the University of Florida after taking the official training course for three days last week. It's a closed-book 90-minute, 60-question test that requires 70% to pass and doesn't reveal your score or the answers you missed. I've been writing custom applications and integrations using JavaScript in the ServiceNow cloud for three years, so I was ready to take the test. But even so, a few questions had me sweating like Albert ... (read more)

I'm a ServiceNow Certified System Administrator

I just passed the test to become a ServiceNow Certified System Administrator. I'm in classes this week to take the test for developer certification next. Certifications are a big deal in the ServiceNow world. I'm in my third year programming on the cloud platform but certification hasn't been a priority. I've been at a startup developing products, which is less about marketing yourself and more about marketing those applications. But I've always wanted to seek certification, so I paid for the ... (read more)

We Have Always Been at War with Comment Spammers

This site continues to get 10-30 comment spams a day, along with the occasional comment to an old post that makes it worthwhile to continue offering the opportunity for reader feedback. I'm thinking about switching to a comment form in which the only way to add bold, italics and links is to use buttons that add the formatting in a markup scheme that nobody else on the planet uses. Comments that use HTML or Markdown would be rejected. Coming up with oddball and ultimately futile anti-spam ... (read more)

Welcome, Readers of the Future

I'm working on the next edition of Sams' Teach Yourself Java in 24 Hours. Java 9 has a new HTTP client package, jdk.incubator.http, that makes it a lot easier to GET and POST to web servers and other software that communicates over HTTP. For a demo, I needed a simple server that could take POST requests and do something with them without requiring a user login. I was about to write one when I realized I already had. This blog takes comments submitted over POST. When the book comes out, I'll be ... (read more)

Programming a Confidence Pool for the World Cup

I did some coding yesterday to run a 2014 World Cup confidence pool on SportsFilter. The way a confidence pool works is you assign points to teams based on how confident you are they will win. In this contest, you get point values from 32 down to 1 and assign them to the 32 World Cup teams. The more points you assign a team, the more you are awarded when that team wins or ties a match. Anyone can sign up for a SportsFilter account and play. A prize will be awarded to the winner: the Adidas ... (read more)

Ghost of Computer Author Past

You could tell a lot about an author or conference speaker by tracking the changes made to that person's short bio over the years. Here's how I described myself in 1996 for Java Unleashed, Second Edition, a frankenbook written by 24 authors in the book publishing rush after Java was launched: Rogers Cadenhead is a web developer, computer programmer and writer who created the multi-user games Czarlords and Super Video Poker. Thousands of readers see his work in the Fort Worth Star-Telegram ... (read more)

Creating a Closest Store Locator in PHP

Over the past year, one of my side projects has been the development of shopping directory sites for categories such as wargames, sports cards, videogames and farmers markets, the last of which I launched over the weekend. The sites are running on LAMP (Linux, Apache, MySQL and PHP) using my own code and the Smarty template language, which keeps me from cluttering up my web pages with PHP. As I prepared the newest site, I decided to implement a feature that takes a user-submitted address and ... (read more)

Book Giveaway: Teach Yourself Java in 24 Hours

My newest book, Sams Teach Yourself Java in 24 Hours, Fifth Edition, recently hit bookstores. The book is a for-absolute-beginners guide to programming Java, and this section from chapter one's Q&A section shows how much license I get from the publisher to have fun with the series: Q. Do you only answer questions about Java? A. Not at all. Ask me anything. Q. Okay, why is Prince mad at the Foo Fighters? A. Prince is unhappy that the Foo Fighters performed a cover of his song "Darling Nikki" and ... (read more)