Momento Go-Redis Compatibility Client

What and Why?

This project provides a Momento-backed implementation of go-redis. The goal is to provide a drop-in replacement for go-redis so that you can use the same code with either a Redis server or with the Momento Cache service!

You can use Momento as your cache engine for any Go project that support a redis-backed cache.

Usage

To switch your existing go-redis application to use Momento, you only need to change the code where you construct your client object:

With go-redis client

package redis

import (
  "github.com/redis/go-redis/v9"
)

func initRedisClient() redis.Cmdable {
  // Replace these values with your Redis server's details
  REDIS_HOST := "my.redis-server.com"
  REDIS_PORT := "6379"
  // Create a Redis client
  redisClient := redis.NewClient(&redis.Options{Addr: REDIS_HOST + ":" + REDIS_PORT})
  return redisClient
}

With Momento's go-redis compatibility client

This snippet assumes that a Momento Cache named "default_cache" already exists. You can create a cache using the CreateCache method or using the Momento Console.

package redis

import (
  "context"
  "github.com/momentohq/client-sdk-go/auth"
  "github.com/momentohq/client-sdk-go/config"
  "github.com/momentohq/client-sdk-go/momento"
  momentoredis "github.com/momentohq/momento-go-redis-client/momento-redis"
  "github.com/redis/go-redis/v9"
  "time"
)

func initRedisClient() redis.Cmdable {
  credential, eErr := auth.NewEnvMomentoTokenProvider("MOMENTO_API_KEY")
  if eErr != nil {
    panic("Failed to initialize credentials through API key " + eErr.Error())
  }
  cacheClient, cErr := momento.NewCacheClient(config.LaptopLatest(), credential, 60*time.Second)
  if cErr != nil {
    panic("Failed to initialize Momento cache client " + cErr.Error())
  }
  redisClient := momentoredis.NewMomentoRedisClient(cacheClient, "default_cache")
  return redisClient
}

NOTE: The Momento momento-redis implementation currently supports a subset of Redis commands. We will continue to add support for additional Redis APIs in the future; for more information see the Current Redis API Support section later in this doc.

Installation

go get github.com/momentohq/momento-go-redis-client

Examples

Prerequisites

To run these examples, you will need a Momento API key. You can generate one using the Momento Console

The examples will utilize your API key via the environment variable MOMENTO_API_KEY you set.

Basic Example

In the examples/basic directory, you will find a simple CLI app that does some basic sets and gets on string values. You can also run the tests against your Redis server by providing -useRedis flag along with -host x.x.x.x and -port xxxx.

You can run the example via go run.

Here's an example run against Momento Cache:

cd examples/basic
export MOMENTO_API_KEY=<your momento API key goes here>
go run main.go -cacheName cache

And the output should look something like this:

INFO (CacheClient): Creating cache with name: cache
INFO (CacheClient): Cache 'cache' created successfully

Using Momento as a backend for go-redis with cache name "cache"

-------------------------------------------------
-----------------------SET-----------------------
Successfully set key "Momento" with response "OK"
-----------------------SET-----------------------

-----------------------GET-----------------------
Got response value as "cache" for key "Momento"
-----------------------GET-----------------------

-----------------------DEL-----------------------
Delete successful for key "Momento" with response "1"
-----------------------DEL-----------------------

-----------------------SETNX-----------------------
Successfully set key "Momento" with response "true"
-----------------------SETNX-----------------------

-----------------------EXPIRE-----------------------
Successfully set expiration for key "Momento" with response "true"
-----------------------EXPIRE-----------------------

-----------------------TTL-----------------------
Successfully received remaining ttl 1m39.969s for key "Momento"
-----------------------TTL-----------------------

INFO (CacheClient): Deleting cache with name: cache
INFO (CacheClient): Cache 'cache' deleted successfully

To run against Redis, the command will look like:

 go run main.go -useRedis -host 127.0.0.1 -port 6379

Current Redis API Support

This library supports the most popular Redis APIs, but does not yet support all Redis APIs.

Scalar Operations	SET, GET, DEL, SETNX, EXPIRE, TTL
Sorted Set Operations	ZADD, ZRANGEBYSCORE, ZRANGEBYSCOREWITHSCORES, ZREVRANGEBYSCORE, ZREVRANGEBYSCOREWITHSCORES
Dictionary Operations	HSET

We will be adding support for additional APIs in the future. If there is a particular API that you need support for, please drop by our Discord or e-mail us at [email protected] and let us know!

In the meantime, if you call a method from the momento-redis API that we do not yet support, you will get a panic for UnsupportedOperationError letting you know that the method is not yet implemented.

Go-Lang Compile-Time API Checking

If you'd like compile-time checking to tell you if you are using any APIs that we don't yet support, we provide our own MomentoRedisCmdable interface, which is a fully compatible subset of the official go-redis interface Cmdable, but explicitly lists out the APIs that we currently support.

With a one-line change to your initialization call, you get back an instance of this interface instead of the default redis.Cmdable interface. Then the go-lang compiler will catch any calls your code is making to Redis API methods that we don't yet support, so you'll know before you even try to run the code.

All you need to do is type the MomentoRedisClient object we instantiated above as MomentoRedisCmdable. Here's what it looks like:

package redis

import (
  "context"
  "github.com/momentohq/client-sdk-go/auth"
  "github.com/momentohq/client-sdk-go/config"
  "github.com/momentohq/client-sdk-go/momento"
  momentoredis "github.com/momentohq/momento-go-redis-client/momento-redis"
  "time"
)

// only change in the function definition from before and the body remains the same
func initRedisClient() momentoredis.MomentoRedisCmdable {
  credential, eErr := auth.NewEnvMomentoTokenProvider("MOMENTO_API_KEY")
  if eErr != nil {
    panic("Failed to initialize credentials through API key " + eErr.Error())
  }
  cacheClient, cErr := momento.NewCacheClient(config.LaptopLatest(), credential, 60*time.Second)
  if cErr != nil {
    panic("Failed to initialize Momento cache client " + cErr.Error())
  }
  // create cache; it resumes execution normally incase the cache already exists
  _, createErr := cacheClient.CreateCache(context.Background(), 
                    &momento.CreateCacheRequest{CacheName: "default_cache"})
  if createErr != nil {
    panic("Failed to create cache with cache name default cache \n" + createErr.Error())
  }
  redisClient := momentoredis.NewMomentoRedisClient(cacheClient, "default_cache")
  return redisClient
}

Exactly the same initialization call as before other than the momento_redis.MomentoRedisCmdable type, and now you get compile-time compatibility checking!*

If you try this, and your code doesn't compile because we are missing APIs that you need, please do reach out to us!

* Note that some flags are not supported. You may get a runtime error (UnsupportedOperationError) for those.

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For more info, visit our website at https://gomomento.com!