Golang

Introductory Go Programming Tutorial

Jay Ts — Thu, 24 Jan 2019 13:00:00 +0000

How to get started with this useful new programming language.

You've probably heard of Go. Like any new programming language, it took a while to mature and stabilize to the point where it became useful for production applications. Nowadays, Go is a well established language that is used in web development, writing DevOps tools, network programming and databases. It was used to write Docker, Kubernetes, Terraform and Ethereum. Go is accelerating in popularity, with adoption increasing by 76% in 2017, and there now are Go user groups and Go conferences. Whether you want to add to your professional skills or are just interested in learning a new programming language, you should check it out.

Go History

A team of three programmers at Google created Go: Robert Griesemer, Rob Pike and Ken Thompson. The team decided to create Go because they were frustrated with C++ and Java, which through the years have become cumbersome and clumsy to work with. They wanted to bring enjoyment and productivity back to programming.

The three have impressive accomplishments. Griesemer worked on Google's ultra-fast V8 JavaScript engine used in the Chrome web browser, Node.js JavaScript runtime environment and elsewhere. Pike and Thompson were part of the original Bell Labs team that created UNIX, the C language and UNIX utilities, which led to the development of the GNU utilities and Linux. Thompson wrote the very first version of UNIX and created the B programming language, upon which C was based. Later, Thompson and Pike worked on the Plan 9 operating system team, and they also worked together to define the UTF-8 character encoding.

Why Go?

Go has the safety of static typing and garbage collection along with the speed of a compiled language. With other languages, "compiled" and "garbage collection" are associated with waiting around for the compiler to finish and then getting programs that run slowly. But Go has a lightning-fast compiler that makes compile times barely noticeable and a modern, ultra-efficient garbage collector. You get fast compile times along with fast programs. Go has concise syntax and grammar with few keywords, giving Go the simplicity and fun of dynamically typed interpreted languages like Python, Ruby and JavaScript.

The idea of Go's design is to have the best parts of many languages. At first, Go looks a lot like a hybrid of C and Pascal (both of which are successors to Algol 60), but looking closer, you will find ideas taken from many other languages as well.

Go is designed to be a simple compiled language that is easy to use, while allowing concisely written programs that run efficiently. Go lacks extraneous features, so it's easy to program fluently, without needing to refer to language documentation while programming. Programming in Go is fast, fun and productive.

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FOSS Project Spotlight: Pydio Cells, an Enterprise-Focused File-Sharing Solution

Italo Vignoli — Fri, 13 Jul 2018 14:20:00 +0000

by Italo Vignoli

Pydio Cells is a brand-new product focused on the needs of enterprises and large organizations, brought to you from the people who launched the concept of the open-source file sharing and synchronization solution in 2008. The concept behind Pydio Cells is challenging: to be to file sharing what Slack has been to chats—that is, a revolution in terms of the number of features, power and ease of use.

In order to reach this objective, Pydio's development team has switched from the old-school development stack (Apache and PHP) to Google's Go language to overcome the bottleneck represented by legacy technologies. Today, Pydio Cells offers a faster, more scalable microservice architecture that is in tune with dynamic modern enterprise environments.

In fact, Pydio's new "Cells" concept delivers file sharing as a modern collaborative app. Users are free to create flexible group spaces for sharing based on their own ways of working with dedicated in-app messaging for improved collaboration.

In addition, the enterprise data management functionality gives both companies and administrators reassurance, with controls and reporting that directly answer corporate requirements around the General Data Protection Regulation (GDPR) and other tightening data protection regulations.

Pydio Loves DevOps

In tune with modern enterprise DevOps environments, Pydio Cells now runs as its own application server (offering a dependency-free binary, with no need for external libraries or runtime environments). The application is available as a Docker image, and it offers out-of-the-box connectors for containerized application orchestrators, such as Kubernetes.

Also, the application has been broken up into a series of logical microservices. Within this new architecture, each service is allocated its own storage and persistence, and can be scaled independently. This enables you to manage and scale Pydio more efficiently, allocating resources to each specific service.

The move to Golang has delivered a ten-fold improvement in performance. At the same time, by breaking the application into logical microservices, larger users can scale the application by targeting greater resources only to the services that require it, rather than inefficiently scaling the entire solution.

Built on Standards

The new Pydio Cells architecture has been built with a renewed focus on the most popular modern open standards:

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Back Up GitHub and GitLab Repositories Using Golang

Amit Saha — Mon, 04 Jun 2018 21:46:37 +0000

by Amit Saha

Want to learn Golang and build something useful? Learn how to write a tool to back up your GitHub and GitLab repositories.

GitHub and GitLab are two popular Git repository hosting services that are used to host and manage open-source projects. They also have become an easy way for content creators to be able to invite others to share and collaborate without needing to have their own infrastructure setup.

Using hosted services that you don't manage yourself, however, comes with a downside. Systems fail, services go down and disks crash. Content hosted on remote services can simply vanish. Wouldn't it be nice if you could have an easy way to back up your git repositories periodically into a place you control?

If you follow along with this article, you will write a Golang program to back up git repositories from GitHub and GitLab (including custom GitLab installations). Being familiar with Golang basics will be helpful, but not required. Let's get started!

Hello Golang

The latest stable release of Golang at the time of this writing is 1.8. The package name is usually golang, but if your Linux distro doesn't have this release, you can download the Golang compiler and other tools for Linux. Once downloaded, extract it to /usr/local:


$ sudo tar -C /usr/local -xzf 
$ export PATH=$PATH:/usr/local/go/bin

Opening a new terminal and typing $ go version should show the following:


$ go version
go version go1.8 linux/amd64

Let's write your first program. Listing 1 shows a program that expects a -name flag (or argument) when run and prints a greeting using the specified name. Compile and run the program as follows:


$ go build listing1.go
$ ./listing1 -name "Amit"
Hello Amit

$ ./listing1
./listing1
2017/02/18 22:48:25 Please specify your name using -name
$ echo $?
1

If you don't specify the -name argument, it exits printing a message with a non-zero exit code. You can combine both compiling and running the program using go run:


$ go run listing1.go -name Amit
2017/03/04 23:08:11 Hello Amit

Listing 1. Example Program listing1.go

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