Part 1 — Utility Functions I have been interested in image manipulation for some time. Last year I worked on a small package that does simple image manipulation using Go’s standard image package: github.com/KorayGocmen/image Let’s look at how to read an image from a provided file path and creating an image object. …

After using Sequelize in my Express applications for the past 6 years, this is how I write my migrations and models for all my Nodejs applications. Install sequelize with npm first and initialize the project with “sequelize init”. That should create the “models”, “migrations” and “seeders” folders as well as…

After using Sequelize in my Express applications for the past 6 years, I’ve landed on a database file that I’ve been using for all my Nodejs applications. Install sequelize with npm first and initialize the project with “sequelize init”. That should create the “models”, “migrations” and “seeders” folders as well…

I’ve writing production level Go code for the past 4 years now, something that I’ve been using since the beginning is the timer events in Go. I use timer events like how I would use cron jobs, to run a function or a script in a certain time interval. I…

The default HTTP client in Go uses the default DNS resolver available on the machine. There are some cases where you might want to use a different DNS resolver. I want to quickly show how you can change the DNS resolver for the default HTTP client. We are using this…

I’m not a big fan of the built-in `dgram` and `net` libraries in Nodejs, but it’s really easy to create sockets and write networking applications with Nodejs. One of the biggest issues I’m constantly seeing is the lack of cleanup functionalities when using the socket libraries in Nodejs. This code…

Part 5— The worker The entry point of the worker is the worker/worker.go file which contains the init and the main functions. Main functions call 2 functions async, which are to start the GRPC server and to register on the scheduler. // worker/worker.go package main import ( "fmt" "log" "os" "os/signal"…

Part 4 — The scheduler The entry point of the scheduler is the scheduler/scheduler.go file which contains the init and the main functions. Main functions call 2 functions async, which are to start the HTTP server (API) and the GRPC server. // scheduler/scheduler.go package main import ( "log" "os" "os/signal" "syscall" ) func init()…

Part 3 — The worker overview Workers expose a GRPC-server to communicate with the scheduler. The main job of workers is to run specific jobs requested by the scheduler and report on those jobs. Jobs can be ruby/python/bash scripts or any executables available on the worker machine. // jobsMutex is the lock to access jobs map. //…