golang

golang

Write Your Own Go Linters with Parser Package

This post is also posted on Mercari Engineering Blog as one of the entries on Merpay Advent Calendar 2019 What's a Linter? Why Do I Need One? Linters are tools that help to improve code readability, consistency, and maintainability by catching code smell and anti-patterns. Linters play an

golang

Method Has Pointer Receiver Error

StackOverflow Reference If an interface variable is assigned with a non-pointer value of a concrete type. There will be an error like: ./main.go:31:4: cannot use x (type X) as type Y in assignment: Foo does not implement Y (Z method has pointer receiver) The example code is

golang

A Quick Start on Protocol Buffer with Go

Create a .proto file First, we need to install buffer protocol tool: # Protocol Buffer compiling tool brew install protobuf # With Go plugin go get -u github.com/golang/protobuf/protoc-gen-go Then we create a quick example file, like person.proto: syntax="proto3"; package main; message Person { string name

golang

Retrieving Field Name & Value in Struct

We can use reflect package for retrieving field name and value dynamically from a struct. package main import ( "fmt" "reflect" ) type Foo struct { aa string ff string } func main() { foo := Foo{"x", "y"} t := reflect.TypeOf(foo) // => Returns a type Type

Using Map in Go

A simple list of multiple usages of map in Go: package main import "fmt" func main() { // Like in Ruby, values in maps passed to functions are original values, // modifying the values will modify the original. // Declaration: // var my_map map[string]string, or: my_map := make(map[string]

golang

Deploying Gin App to Ubuntu VPS

Here's how to deploy a Gin app to vps once you've initated and ssh in a VPS running Ubuntu 14.04. Installing Nginx & Dependencies Install some libraries that most environments require. sudo apt-get update sudo apt-get install build-essential libssl-dev libyaml-dev libreadline-dev openssl curl git-core zlib1g-dev

golang

GORM: A Simple Guide on CRUD

GORM is a ORM in Golang for handling relational databases. This is a brief walkthrough of all necessary commands and functions you might wanna use. Connection Like every other Go pacakge: import ( "github.com/jinzhu/gorm" // import "github.com/jinzhu/gorm/dialects/mysql" // import _ "github.

golang

Watch File Changes with Godo

Godo is a make tool in Golang inspired by tools like rake and gulp in other languages. Similarly, it serves to execute tasks, watch changes, and can be called directly from command line. It's a new tool and is still growing. There might not be as many tools

golang

Concatenating Strings in Go Efficiently

It's common to concatenate a series of strings to a target string. In Go, we can do it simply by: func concatenate() string { target := "" strings := []string{"foo", "bar", "baz"} for _, string := range strings { target += string } return target } However, It can

golang

Serving Static HTML in Gin

Gin is a web framework in Go. It serves to offer a better control of requests, responses, and routing, basically like Sinatra in Ruby. The Basics It is easy to initiate a server and render the content we disinate: package main import ( "github.com/gin-gonic/gin" "net/

Basic Object-Oriented Programming in Go

Is Go an object-oriented language? The official website offers an answer to this: "Yes and No". Basically Go does not intend to serve as an full object-oriented language like Ruby, but you can use it only in that way, like we do it in JavaScript. In fact, Go