Toolbox

A simple example of how to create a reusable Go module with commonly used tools.

The included tools are:

• Read JSON
• Write JSON
• Produce a JSON encoded error response
• Upload a file to a specified directory
• Download a static file
• Get a random string of length n
• Post JSON to a remote service
• Create a directory, including all parent directories, if it does not already exist

Not for production -- used in a course.

Installation

go get -u github.com/tsawler/toolbox

Usage

package main

import (
	"fmt"
	"github.com/tsawler/toolbox"
)

func main() {
	// create a variable of type toolbox.Tools, so we can use this variable
	// to call the methods on that type
	var tools toolbox.Tools

	// get a random string
	rnd := tools.RandomString(10)
	fmt.Println(rnd)
}

Working with JSON

In a handler, for example:

// JSONPayload is the type for JSON data that we receive
type JSONPayload struct {
    Name string `json:"name"`
    Data string `json:"data"`
}

// SomeHandler is the handler to accept a post request consisting of json payload
func (app *Config) SomeHandler(w http.ResponseWriter, r *http.Request) {
    var tools toolbox.Tools
    
    // read json into var
    var requestPayload JSONPayload
    _ = tools.ReadJSON(w, r, &requestPayload)
	
    // do something with the data here...
    
    // create the response we'll send back as JSON
    resp := toolbox.JSONResponse{
        Error:   false,
        Message: "logged",
    }
    
    // write the response back as JSON
    _ = tools.WriteJSON(w, http.StatusAccepted, resp)
}

Download a file

To download a static file, and force it to download instead of displaying in a browser:

// DownloadAFile downloads an arbitrary file
func (app *Config) DownloadAFile(w http.ResponseWriter, r *http.Request) {
    var tools toolbox.Tools

    tools.DownloadStaticFile(w, r, "./data", "file.pdf", "file.pdf")
}

Creating a directory

To create a directory if it does not already exist:

// SomeHandler is some kind of handler
func (app *Config) SomeHandler(w http.ResponseWriter, r *http.Request) {
    var tools toolbox.Tools

    err := tools.CreateDirIfNotExist("./myDir")
    if err != nil {
        // do something with the error...
    }
	
    // keep going in the handler...
}