IMMUGORM

This repository is a driver for immudb. to act as a database for GORM.

Quick Start

Clone immudb repository, compile immudb and launch it:

git clone https://github.com/codenotary/immudb
make immudb
./immudb

Below see an example on how to get GORM to work with immudb:

package main

import (
    immugorm "github.com/codenotary/immugorm"
    "gorm.io/gorm"
    "gorm.io/gorm/logger"
)

type Product struct {
    ID     int `gorm:"primarykey"`
    Code   string
    Price  uint
    Amount uint
}

func main() {
    db, err := gorm.Open(immugorm.Open("immudb://immudb:immudb@127.0.0.1:3322/defaultdb?sslmode=disable", &immugorm.ImmuGormConfig{Verify: false}), &gorm.Config{
        Logger: logger.Default.LogMode(logger.Info),
    })
    if err != nil {
        panic(err)
    }

    // Migrate the schema
    err = db.AutoMigrate(&Product{})
    if err != nil {
        panic(err)
    }
    // Create
    err = db.Create(&Product{Code: "D43", Price: 100, Amount: 500}).Error
    if err != nil {
        panic(err)
    }
    // Read
    var product Product
    // find just created one
    err = db.First(&product).Error
    if err != nil {
        panic(err)
    }
    // find product with code D42
    err = db.First(&product, "code = ?", "D43").Error
    if err != nil {
        panic(err)
    }
    // Update - update product's price to 200
    err = db.Model(&product).Update("Price", 888).Error
    if err != nil {
        panic(err)
    }

    // Update - update multiple fields
    err = db.Model(&product).Updates(Product{Price: 200, Code: "F42"}).Error
    if err != nil {
        panic(err)
    }

    err = db.Model(&product).Updates(map[string]interface{}{"Price": 200, "Code": "F42"}).Error
    if err != nil {
        panic(err)
    }

    // Delete - delete product
    err = db.Delete(&product, product.ID).Error
    if err != nil {
        panic(err)
    }
}

Open with Immudb Options

It's possible open a connection with immudb options to provide more control over the connection or enable some features that are not available by standard DSN.

import (
    "github.com/codenotary/immudb/pkg/client"
    immugorm "github.com/codenotary/immugorm"
    "gorm.io/gorm"
    "gorm.io/gorm/logger"
)

...

opts := client.DefaultOptions()

opts.Username = "immudb"
opts.Password = "immudb"
opts.Database = "defaultdb"
opts.HealthCheckRetries = 10

db, err := gorm.Open(immugorm.OpenWithOptions(opts, &immugorm.ImmuGormConfig{Verify: false}), &gorm.Config{
    Logger: logger.Default.LogMode(logger.Info),
})

IMMUDB SPECIAL FEATURES

TamperProof read

Immugorm is able to take benefits from immudb tamperproof capabilities. It's possible to activate tamperproof read by setting Verify: true when opening db. The only difference is that verifications returns proofs needed to mathematically verify that the data was not tampered.

Note that generating that proof has a slight performance impact.

    db, err := gorm.Open(immugorm.Open(opts, &immugorm.ImmuGormConfig{Verify: true}), &gorm.Config{})

Timetravel

Time travel allows reading data from SQL as if it was in some previous state.

The state is indicated by transaction id, that is a monotonically increasing number that is assigned to each transaction by immudb Each operation is assigned a transaction id.

db.Clauses(immugorm.BeforeTx(9)).Last(&entity, 1)

Warnings

This is an experimental software. The API is not stable yet and may change without notice. There are limitations:

• missing support related to altering or deleting already existent elements on schema. No drop table, index, alter table or column
• missing float type
• missing left join
• no support for composite primary key
• no support for polymorphism
• no support for foreign constraints
• is mandatory to have a primary key on tables
• no default values
• order is limit to one indexed column
• group by not supported
• no support for prepared statements
• not condition missing
• no transaction with savepoint
• no nested transactions
• having nor yet supported