bookstore

qor tutorial

Intro

QOR is a set of modules to written in go.

Prerequisites

• GoLang 1.x+ (at the time of writing I am using >=1.4.0 versions)

• Install qor git clone https://github.com/qor/qor.git

NB: I you clone qor and use it from your own account you will have to create a symlink like this:

go/src/github.com/qor [qor] $ ln -s ../YOUR_GITHUB_USRNAME/qor/ qor

• A database - for example PostgreSQL or MySQL

• go into the qor source directory and run go get .

• Optional: fresh being installed:

  go get github.com/pilu/fresh

fresh is not necessary to use qor, but it will make your life easier when playing with the tutorial: it monitors for file changes and automatically recompiles your code every time something has changed.

A bookstore

We want to create a simple bookstore application. We will start by building a catalog of books and then later add a storefront that can take orders from users that can then be processed in a backoffice application by the store owner.

Create a database and a db user for the tutorial

Before we dive into our models we need to create a database:

mysql> DROP DATABASE IF EXISTS qor_bookstore;
mysql> CREATE DATABASE qor_bookstore DEFAULT CHARACTER SET utf8mb4;

mysql> CREATE USER 'qor'@'localhost' IDENTIFIED BY 'qor';
mysql> CREATE USER 'qor'@'%' IDENTIFIED BY 'qor';


mysql> GRANT ALL ON qor_bookstore.* TO 'qor'@'localhost';
mysql> FLUSH PRIVILEGES;

You should now be able to connect to your database from the console like this:

$ mysql -uqor -p --database qor_bookstore


INSERT INTO users (name) VALUES ("admin");

Create the basic models

We will need the following two models to start with:

• Author
• Book

The Author model is very simple:

type Author struct {
    gorm.Model
    Id   int64
    Name string
}

All qor models "inherit" from gorm.model. (see https://github.com/jinzhu/gorm). Our author model for now only has an Id and a Name.

The Bookmodel has a few more fields:

type Book struct {
	gorm.Model
	Id          int64
	Title       string
	Synopsis    string
	ReleaseDate time.Time
	Authors     []*Author `gorm:"many2many:book_authors"`
	Price       float64
}

The only interesting part here is the gorm struct tag: gorm:many2many:book_authors"; It tells gorm to create a join table book_authors.

That's almost it: If you look at you can see an init() function at the end: It sets up a db connection and DB.AutoMigrate(&Author{}, &Book{}) tells QOR to automatically create the tables for our models.

Let's start the tutorial app once to see what happens when models get auto-migrated.

go/src/github.com/qor/qor/example/tutorial/bookstore [bookstore (master)] $ fresh

If you now check your db you would see something like this:

mysql> show tables;
+-------------------------+
| Tables_in_qor_bookstore |
+-------------------------+
| authors                 |
| book_authors            |
| books                   |
| users                   |
+-------------------------+
4 rows in set (0.00 sec)

mysql> describe authors;
+------------+--------------+------+-----+---------+----------------+
| Field      | Type         | Null | Key | Default | Extra          |
+------------+--------------+------+-----+---------+----------------+
| id         | int(11)      | NO   | PRI | NULL    | auto_increment |
| created_at | timestamp    | YES  |     | NULL    |                |
| updated_at | timestamp    | YES  |     | NULL    |                |
| deleted_at | timestamp    | YES  |     | NULL    |                |
| name       | varchar(255) | YES  |     | NULL    |                |
+------------+--------------+------+-----+---------+----------------+
5 rows in set (0.00 sec)

As you can see QOR/gorm added an id field as well as timestamp fields to keep track of creation, modification, and deletion times. We can ignore this for now - the main point is that you create your models without a unique identifier - QOR/gorm will do this for you automatically. (TODO: @jinzhu please confirm)

NB: If you add new fields to your model they will get added to the database automatically with DB.AutoMigrate - deletions or changes of eg. the type will not be automigrated. (TODO: @jinzhu please confirm)

Admin

If the bookstore app is not yet running, start it by running fresh in the bookstore directory:

go/src/github.com/qor/qor/example/tutorial/bookstore [bookstore (master)] $ fresh

Go to http://localhost:9000/admin and you should see the main admin interface:

The Menu at the top gets created by adding your models as resources to the admin:

Admin := admin.New(&qor.Config{DB: &db})
Admin.AddResource(
	&Author{},
	&admin.Config{Menu: []string{
		"Author Management"},
		Name: "Author",
	},
)

you can see how the rest of the resources was added in main.go, the db object referenced here is set up in models.go

Go ahead an add an author and then a book via the admin.

Meta Module - Controlling display and editable fields in the admin

First frontend

QOR does not provide any templating or routing support - use whatever library is best fit for your needs. In this tutorial we will use gin

List of Books

MediaLibrary - Adding product images

qor/media_library

Base is the low level object to deal with images offering cropping, resizing, and URL contruction for images.

Shopping

INERT INTO users (name) VALUES ("admin");

First we need users that can register to buy books

Add Locales && translations

-- later

Add customers (model)

Add orders