grimoire

Database access layer for golang

Description

Grimoire is a flexible ORM for golang. It features flexible query API and builtin validation. It currently supports MySQL, PostgreSQL and SQLite3 but a custom adapter can be implemented easily using the Adapter interface.

Programming language: Go

License: MIT License

Tags: SQL     Database     ORM     Validation    

Latest version: v1.5.0

README

grimoire

:warning: Grimoire V2 is available as REL and Changeset package.

Grimoire is a database access layer inspired by Ecto. It features a flexible query API and built-in validation. It currently supports MySQL, PostgreSQL, and SQLite3 but a custom adapter can be implemented easily using the Adapter interface.

Features:

• Query Builder
• Association Preloading
• Struct style create and update
• Changeset Style create and update
• Builtin validation using changeset
• Multi adapter support
• Logger

Motivation

Common go ORM accepts struct as a value for modifying records which has a problem of unable to differentiate between an empty, nil, or undefined value. It's a tricky problem especially when you want to have an endpoint that supports partial updates. Grimoire attempts to solve that problem by integrating Changeset system inspired from Elixir's Ecto. Changeset is a form like entity which allows us to not only solve that problem but also help us with casting, validations, and constraints check.

Install

go get github.com/Fs02/grimoire

Quick Start

package main

import (
    "time"

    "github.com/Fs02/grimoire"
    "github.com/Fs02/grimoire/adapter/mysql"
    "github.com/Fs02/grimoire/changeset"
    "github.com/Fs02/grimoire/params"
)

type Product struct {
    ID        int
    Name      string
    Price     int
    CreatedAt time.Time
    UpdatedAt time.Time
}

// ChangeProduct prepares data before database operation.
// Such as casting value to appropriate types and perform validations.
func ChangeProduct(product interface{}, params params.Params) *changeset.Changeset {
    ch := changeset.Cast(product, params, []string{"name", "price"})
    changeset.ValidateRequired(ch, []string{"name", "price"})
    changeset.ValidateMin(ch, "price", 100)
    return ch
}

func main() {
    // initialize mysql adapter.
    adapter, err := mysql.Open("root@(127.0.0.1:3306)/db?charset=utf8&parseTime=True&loc=Local")
    if err != nil {
        panic(err)
    }
    defer adapter.Close()

    // initialize grimoire's repo.
    repo := grimoire.New(adapter)

    var product Product

    // Inserting Products.
    // Changeset is used when creating or updating your data.
    ch := ChangeProduct(product, params.Map{
        "name":  "shampoo",
        "price": 1000,
    })

    if ch.Error() != nil {
        // handle error
    }

    // Changeset can also be created directly from json string.
    jsonch := ChangeProduct(product, params.ParseJSON(`{
        "name":  "soap",
        "price": 2000,
    }`))

    // Create products with changeset and return the result to &product,
    if err = repo.From("products").Insert(&product, ch); err != nil {
        // handle error
    }

    // or panic when insertion pailed
    repo.From("products").MustInsert(&product, jsonch)

    // Querying Products.
    // Find a product with id 1.
    repo.From("products").Find(1).MustOne(&product)

    // Updating Products.
    // Update products with id=1.
    repo.From("products").Find(1).MustUpdate(&product, ch)

    // Deleting Products.
    // Delete Product with id=1.
    repo.From("products").Find(1).MustDelete()
}

Examples

• Todo API

Documentation

Guides: https://fs02.github.io/grimoire

API Documentation: https://godoc.org/github.com/Fs02/grimoire

License

Released under the MIT License