Computing

A command-line processor, as its name implies, is a software appliance intended to be executed from a command-line in pipelined fashion. Most operating systems are equipped with bunch of utilities that can be ingeniously combined to create powerful mini programs for transforming data. We will focus our attention here on jq specialized to mangle JSON data similarly how sed crunches textual content. You can easily start using it by issuing brew install jq on macOS (or download it for other operating systems). Nonetheless, even without placing anything on your machine, there is also a nice playground for trying out things online. The following example illustrates what sort of actions could be crafted into a unified instruction, i.e., mini program that may be reused as a whole: > echo "A test string." | jq -R "ascii_upcase | gsub(\"STRING\"; \"CONTENT\")" "A TEST CONTENT." The input is piped into jq as an ordinary string (this is hi

In all creative disciplines fundamental ideas reoccur in different shapes. This cannot be truer in computer science and software engineering. Advances in technology even enables old ideas to appear as pure novelties. In this article we will focus on an intellectual toolbox associated with morphing existing ideas, concepts, and technique to fit new scenarios. This is tightly connected with generalization and pattern matching, which are both prominent ingredients in achieving success in professional practice and various competitive activities. The latter is examined in more detail in my article about competitive software engineering . To make the point clear let us use a concrete example from Petlja , a website maintained by the Serbian Mathematical Society, which also organizes official competitions in mathematics and programming. The problem we will use is called Mingo . Below is its description translated to English. Problem Description Now, after completing the competition, Miroslav

JSON API provides a systematic method of specifying Level 3 REST APIs in JSON. It has a registered hypermedia type of application/vnd.api+json issued by the Internet Assigned Numbers Authority (IANA). The next list briefly enrolls the most salient features and benefits of JSON API (see my book Creating Maintainable APIs for more information): It is a hypermedia-driven conventional interface : This is a fundamental difference between JSON API and other pure message formats. The JSON API, besides establishing a shared convention regarding message formats, also encompasses rules for how to interact with services (it specifies an assumed API). For example, JSON API contains instructions on how services should fetch, create, update, and delete resources, specify pagination, pass query parameters, and so on. This trait of JSON API is tightly related to the concept of openness in distributed systems. An open distributed system mandates certain rules regarding how services should be implem