# Tutorial Notebook: A simple CRUD app with Go

> Tutorials Notebook is a blog series where I write-up my thoughts & lessons learned after completing a tutorial. A large credit should go to the authors who created the tutorials in the first place.

Tutorial: [https://codewithmukesh.com/blog/implementing-crud-in-golang-rest-api/](https://codewithmukesh.com/blog/implementing-crud-in-golang-rest-api/) by @[Mukesh Murugan](@iammukeshm)

---

Lately, a couple of things have been motivating me to learn and get better with GoLang.

1. There's a project that I've wanted to build for a friend since last year;
    
2. I'm ending up working more and more in our codebase at work which is all written in Go.
    

So I figured I'd start from scratch and work towards the goal of building that app for my friend.

Breaking down that task - one thing I'll need to do is create an API that can handle incoming requests. Today, I completed a tutorial to create a very basic app that would enable a user to Create, Retrieve, Update and Delete (CRUD) a product from a database.

![](https://cdn.hashnode.com/res/hashnode/image/upload/v1675444193068/01fb0c98-aa01-4ba3-87e0-c62f5848f8d1.png align="center")

## Things I Learned

1. MySQL. It'd been a while since I'd created a database. Helpful commands on mac:
    
    * `brew install mysql` - Install the MySQL server on mac.
        
    * `brew services start mysql` - Start the MySQL server
        
    * `mysql -u root` - Login with username `root` and no password (default)
        
    * `create database <name>;`
        
    * `use database <name>;`
        
    * `show tables;`
        
2. VS Code Shortcut: Typing in `hand` (+ enter) in VS Code will automatically create a HTTP response handler for you.
    
3. Go Pointers
    

* You can define what an object is like. In this example, a `product` consists of 4 pieces of information.
    

```go
type Product struct {
	ID          uint    `json:"id"`
	Name        string  `json:"name"`
	Price       float64 `json:"price"`
	Description string  `json:"description"`
}
```

* A pointer to that struct is used in this HTTP API handler for `POST` ing (creating) products.
    

```go
func CreateProduct(w http.ResponseWriter, r *http.Request) {
	w.Header().Set("Content-Type", "application/json")
	var product entities.Product
	json.NewDecoder(r.Body).Decode(&product)
	database.Instance.Create(&product)
	json.NewEncoder(w).Encode(product)
}
```

Where the important lines are:

`var product entities.Product` - this line creates an "empty" product that contains the 0 (or nil) values defined int he struct.

`json.NewDecoder(r.Body).Decode(&product)` - In this line, we use the memory address of variable `product` as denoted by the `&` to "fill" it with relevant data.

1. You can even make cURL commands right from VS Code using the REST Client extension.
    

![](https://cdn.hashnode.com/res/hashnode/image/upload/v1675443545482/117dd18c-2855-4c1d-909d-5f953454abe7.png align="center")