Accurate pricing for complex cloud projects is a key requirement for success. Unfortunately the sheer number of variables and the ever changing landscape of pricing, shifting of regions, etc. makes it extremely difficult to keep a pricing model up to date as the project evolves. Google Cloud anticipated that when they created https://cloud.google.com/billing/v1/how-tos/catalog-api. Using this API, it’s possible to get up to the moment pricing for all Google Cloud SKUs. These pricing details can then be added to a Google Sheet or other dataset to create flexible cost models for projects of any......
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May applications require authentication to secure protected resources. While standards like oAuth accommodate sharing resources between applications, more variance exists in implementations of securing the app in the first place. A recent standard, JWT, provides a mechanism for creating tokens with embedded data, signing these tokens and even encrypting them when warranted. This post explores how individual resource functions can be protected using JWT. The solution involves first creating a function decorator to perform the authentication step. Each protected resource call is then decorated with the authentication function and subsequent authorization can be......
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Hopefully it’s obvious that separating configuration from application code is always a good idea. One simple and effective way I’ve found to do this in my python (think bottle, flask, etc.) apps is with a simple JSON configuration file. Choosing JSON makes sense for a few reasons: Easy to read (for humans) Easy to consume (by your application Can be version alongside application code Can be turned into a configuration REST service Here’s a short example of how to do this for a simple python application that uses MongoDB. First the configuration file.......
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Stackato, which is released by ActiveState, extends out of the box CloudFoundry. It adds a web interface and a command line client (‘stackato’), although the existing ‘cf’ command line client still works (as long as versions match up). Stackato includes some autoscale features and a very well done set of documentation. ActiveState publishes various VM images that can be used to quickly spin up a development environment. These include images for VMWare, KVM and VirtualBox, among others. In this post I’ll walk through getting a Stackato environment running on Windows using VirtualBox. Install......
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About 13 years ago I created my first integration with Authorize.net for a client who wanted to accept credit card payments directly on his website. The internet has changed a lot since then and the frequency of fraud attempts has increased. One credit card fraud signature I identified while reviewing my server logs for one of my e-commerce websites was consistent. I refer to this is a shotgun attack, since the hacker sends through hundreds of credit card attempts. Here’s how it works and what to look for. All requests from a single......
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I read that Hadoop supports scripts written in various languages other than Java, such as Python. Since I’m a fan of python, I wanted to prove this out. It was my good fortune to find an excellent post by Michael Noll that walked me through the entire process of scripting in Python for Hadoop. It’s an excellent post and worked as written for me in Hadoop 2.2.0. How hadoop processes scripts from other languages (stdin/stdout) In order to accommodate scripts from other languages, hadoop focuses on standard in (stdin) and standard out (stdout).......
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One of my applications runs on a large assortment of hosts split between various data centers. Some of these are redundant pairs and others are in load balanced clusters. They all require a set of identical files which represent static content and other data. rsync was chosen to facilitate replication of data from a source to many targets. What rsync lacked out of the box was a reporting mechanism to verify that the collection of files across target systems was consistent with the source. Existing solutions Before designing my solution, I searched for......
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Several years ago I hosted with webfaction for about a year. I was drawn to them at the time because they allowed SSH access and I could run Java applications on my account. Those were not common features available under shared hosting at the time. I didn’t end up deploying any Java applications and the PHP sites I did deploy routed through webfaction’s nginx to PHP configuration which frequently failed. That meant that many visitors to my site saw nginx errors rather than my web page. When they couldn’t resolve the issue I......
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