grc: a simple gorm cache plugin based on redis

grc is a gorm plugin that provides a simple and flexible way to cache data using redis.

Features

• Easy to use: just add grc as a gorm plugin and use gorm session options to control the cache behavior.
• Flexible to customize: you can configure the cache prefix, ttl, and redis client according to your needs.

Installation

To use grc, you need to have gorm and go-redis installed. You can install them using go get:

go get -u gorm.io/gorm
go get -u github.com/go-redis/redis/v8

Then you can install grc using go get:

go get -u github.com/evangwt/grc

Usage

To use grc, you need to create a gorm cache instance with a redis client and a cache config, and then add it as a gorm plugin. For example:

package main

import (
        "github.com/evangwt/grc"
        "github.com/go-redis/redis/v8"
        "gorm.io/driver/postgres"
        "gorm.io/gorm"
)

func main() {
        // connect to postgres database
        dsn := "host='0.0.0.0' port='5432' user='evan' dbname='cache_test' password='' sslmode=disable TimeZone=Asia/Shanghai"
        db, _ := gorm.Open(postgres.Open(dsn), &gorm.Config{})

        // connect to redis database
        rdb := redis.NewClient(&redis.Options{
                Addr:     "0.0.0.0:6379",
                Password: "123456",
        })

        // create a gorm cache instance with a redis client and a cache config
        cache := grc.NewGormCache("my_cache", grc.NewRedisClient(rdb), grc.CacheConfig{
                TTL:    60 * time.Second,
                Prefix: "cache:",
        })

        // add the gorm cache instance as a gorm plugin
        if err := db.Use(cache); err != nil {
                log.Fatal(err)
        }

        // now you can use gorm session options to control the cache behavior
}

To enable or disable the cache for a query, you can use the grc.UseCacheKey context value with a boolean value. For example:

// use cache with default ttl
db.Session(&gorm.Session{Context: context.WithValue(context.Background(), grc.UseCacheKey, true)}).
                Where("id > ?", 10).Find(&users)

// do not use cache
db.Session(&gorm.Session{Context: context.WithValue(context.Background(), grc.UseCacheKey, false)}).
                Where("id > ?", 10).Find(&users)

To set a custom ttl for a query, you can use the grc.CacheTTLKey context value with a time.Duration value. For example:

// use cache with custom ttl
db.Session(&gorm.Session{Context: context.WithValue(context.WithValue(context.Background(), grc.UseCacheKey, true), grc.CacheTTLKey, 10*time.Second)}).
                Where("id > ?", 5).Find(&users)

For more examples and details, please refer to the example code.

License

grc is licensed under the Apache License 2.0 License. See the LICENSE file for more information.

Contribution

If you have any feedback or suggestions for grc, please feel free to open an issue or a pull request on GitHub. Your contribution is welcome and appreciated.😊