Adventures in IT

An indexed and searchable centralized log is one of those tools that once you've had it you'll wonder how you managed without it.    I've experienced a couple of advantages to using a central log - debugging, monitoring performance, and catching unknown problems. Debugging Debugging becomes easier because instead of poking around grepping text logs on servers you're able to use a GUI to contrast and compare values between different time ranges. A ticket will often include sparse information about the problem and observed error, but if you know more or less when a problem occurred then you can check the logs of all your systems at that time. Problem behaviour in your application can occur as a result of the services you depend on.  A database fault will produce errors in your application, for example. If you log your database errors and your application errors in the same central platform then it's much more convenient to compare behaviour between...

Image: Pixabay Breaking your application down into components can be a useful approach to a "divide and conquer" methodology.  Assigning specific behaviour to a component and then defining interfaces for other components to access it allows you to develop a service driven architecture.  I'm in the process of decomposing a monolithic application into services that will eventually become standalone micro-services.  Part of the task ahead lies in determining the service boundaries, which are analogous to software components for my micro-service application.  I want components to be modular to allow them to be developed and deployed as independently as possible.  I'm using the approach suggested by Eric Evans in his  book on domain driven design  where he describes the concept of "bounded contexts".  I like to think of a bounded context as being for domain models as a namespace is for classes.  These contexts are spaces where a domain mo...

Image: Pixabay SOLID is a mnemonic acronym for five object-oriented design principals that are intended to make software designs more understandable (see Wikipedia ). They were promoted by a chap called Robert C Martin who has been programming since before I was born and is an authority on writing clean code.  Laravel is a PHP framework that implements the model-view-controller (MVC) pattern. A lot of people think that their responsibility for OOP design ends with adopting a framework, but actually Laravel is relatively un-opinionated on your OOP design and you still need to think about writing code that is testable and maintainable.  The reason that SOLID principals matter becomes apparent when you work on a single project for a long time. If you're writing throwaway applications for clients that you never expect to work on again (presumably because the client won't hire you again) then the quality of your code doesn't matter. But if you're the guy stuck ...

Image: Pixabay Calling PHP a double-claw hammer is a bit of an in-joke in the PHP community .  A lot of people bemoan PHP as a language – it's fashionable to do so and it seems to be a way to look clever.   The joke came about from a blog post where somebody pointed out all of the problems with PHP (here's a rebuttal -  https://blog.codinghorror.com/the-php-singularity/   ) Anyway, PHP is a warty language that sucks in academic circles but it doesn't matter because it's really good at web stuff, there are lots of people who know it (so it's cheap to hire), there are lots of libraries and frameworks (so it's cheap and fast to develop in).  The commercial world is willing to overlook the academic warts. I'm busy helping to improve the performance of an API server.  As part of my effort I'm profiling calls to the endpoints.  I'm using Blackfire to generate call graphs and also logging the sql queries that the ORM is producing so that I can check...