Golang

What is Golang?

Go, also known as Golang, is a statically typed, compiled programming language. It was developed in 2007 by Robert Griesemer, Rob Pike, and Ken Thompson at Google but launched in 2009 as an open-source programming language. Go is syntactically similar to C, but with memory safety, garbage collection, structural typing, and CSP-style concurrency.

A Go program file is a simple UTF-8 text file with .go file extension.

There are various online IDEs such as The Go Playground, repl.it, etc. which can be used to run Go programs without installing.

How to install it?

System Requirement:

Go binary distributions are available for these supported operating systems and architectures. Please ensure your system meets these requirements before proceeding. If your OS or architecture is not on the list, you may be able to install from source or use gccgo instead.

Operating systemArchitecturesNotes

FreeBSD 10.3 or lateramd64, 386Debian GNU/kFreeBSD not supportedLinux 2.6.23 or later with glibcamd64, 386, arm, arm64,
s390x, ppc64leCentOS/RHEL 5.x not supported.
Install from source for other libc.macOS 10.10 or lateramd64use the clang or gcc† that comes with Xcode‡ for cgo supportWindows 7, Server 2008R2 or lateramd64, 386use MinGW (386) or MinGW-W64 (amd64) gcc†.
No need for cygwin or msys.

Install the Go tools ¶

If you are upgrading from an older version of Go you must first remove the existing version.

Linux, macOS, and FreeBSD tarballs

Download the archive and extract it into /usr/local, creating a Go tree in /usr/local/go. For example:

tar -C /usr/local -xzf go$VERSION.$OS-$ARCH.tar.gz

Choose the archive file appropriate for your installation. For instance, if you are installing Go version 1.2.1 for 64-bit x86 on Linux, the archive you want is called go1.2.1.linux-amd64.tar.gz.

(Typically these commands must be run as root or through sudo.)

Add /usr/local/go/bin to the PATH environment variable. You can do this by adding this line to your /etc/profile (for a system-wide installation) or $HOME/.profile:

export PATH=$PATH:/usr/local/go/bin

Note: changes made to a profile file may not apply until the next time you log into your computer. To apply the changes immediately, just run the shell commands directly or execute them from the profile using a command such as source $HOME/.profile.

macOS package installer

Download the package file, open it, and follow the prompts to install the Go tools. The package installs the Go distribution to /usr/local/go.

The package should put the /usr/local/go/bin directory in your PATH environment variable. You may need to restart any open Terminal sessions for the change to take effect.

Windows

The Go project provides two installation options for Windows users (besides installing from source): a zip archive that requires you to set some environment variables and an MSI installer that configures your installation automatically.

MSI installer

Open the MSI file and follow the prompts to install the Go tools. By default, the installer puts the Go distribution in c:\Go.

The installer should put the c:\Go\bin directory in your PATH environment variable. You may need to restart any open command prompts for the change to take effect.

Zip archive

Download the zip file and extract it into the directory of your choice (we suggest c:\Go).

Add the bin subdirectory of your Go root (for example, c:\Go\bin) to your PATH environment variable.

Setting environment variables under Windows

Under Windows, you may set environment variables through the “Environment Variables” button on the “Advanced” tab of the “System” control panel. Some versions of Windows provide this control panel through the “Advanced System Settings” option inside the “System” control panel.

Test your installation

Check that Go is installed correctly by setting up a workspace and building a simple program, as follows.

Create your workspace directory, %USERPROFILE%\go. (If you'd like to use a different directory, you will need to set the GOPATH environment variable.)

Next, make the directory src\hello inside your workspace, and in that directory create a file named hello.go that looks like:

package main
import "fmt"
func main() {
 fmt.Printf("hello, world\n")
}

Then build it with the go tool:

C:\> cd %USERPROFILE%\go\src\hello
C:\Users\Gopher\go\src\hello> go build

The command above will build an executable named hello.exe in the directory alongside your source code. Execute it to see the greeting:

C:\Users\Gopher\go\src\hello> hello
hello, world

If you see the “hello, world” message then your Go installation is working.

You can run go install to install the binary into your workspace's bin directory or go clean -i to remove it.

Before rushing off to write Go code please read the How to Write Go Code document, which describes some essential concepts about using the Go tools.

Installing extra Go versions

It may be useful to have multiple Go versions installed on the same machine, for example, to ensure that a package’s tests pass on multiple Go versions. Once you have one Go version installed, you can install another (such as 1.10.7) as follows:

$ go get golang.org/dl/go1.10.7
$ go1.10.7 download

The newly downloaded version can be used like go:

$ go1.10.7 version
go version go1.10.7 linux/amd64

All Go versions available via this method are listed on the download page. You can find where each of these extra Go versions is installed by looking at its GOROOT; for example, go1.10.7 env GOROOT. To uninstall a downloaded version, just remove its GOROOT directory and the goX.Y.Z binary.

Uninstalling Go

To remove an existing Go installation from your system delete the go directory. This is usually /usr/local/go under Linux, macOS, and FreeBSD or c:\Go under Windows.

You should also remove the Go bin directory from your PATH environment variable. Under Linux and FreeBSD you should edit /etc/profile or $HOME/.profile. If you installed Go with the macOS package then you should remove the /etc/paths.d/go file. Windows users should read the section about setting environment variables under Windows.

Major Frameworks for Web Development in Golang -

1. Martini — Martini is really a lightweight web framework. It deals with some fundamental things like exception dealing, routing, and common tricks to do middleware.

2. Gin Gonic — This web framework has quite a similar API like Martini but it performs better for sure. In case you have already used Martini, you are aware of Gin Gonic. Else, it will just take 10 minutes to help you learn Gin. Yes, it’s that much simple.

3. Revel — Revel is a high-productivity web framework for the Go language. It has an impressive feature set and is much more in line with the rails “convention over configuration” approach than most other Go web frameworks.