In this article, we are going to explore the integration of Redis cache in .Net5 Web API application using the 'StackExchange.Redis.Exntensions' library.
Step6:(Optional Step)
Models/Student.cs:
Note:- Microsoft has introduced an 'IDistributedCache' interface in dotnet core which supports different cache stores like In-Memory, Redis, NCache, etc. It is simple and easy to work with 'IDistributedCache', for the Redis store with limited features but if we want more features of the Redis store we can choose to use 'StackExchange.Redis.Extensions'. Click here for Redis Cache Integration Using IDistributedCache Interface.
Overview On StackExchange.Redis.Extnesions Library:
The 'StackExchange.Redis.Extension' library extended from the main library 'StackExchange.Redis'. Some of the key features of this library like:
- Default serialization and deserialization.
- Easy to save and fetch complex objects.
- Search key.
- Multiple Database Access
Setup Redis Docker Instance:
For this sample to use Redis instance locally we will use Docker. If you don't have any prior knowledge on docker, not a problem just follow the steps below. Click here for a video session on Redis docker setup
Note:
Skip this section if you already have redis direct instance or azure or any cloud provider that have redis
Step1:Download docker into our local system "https://docs.docker.com/desktop/". Docker was available for all desktop operating systems.
Step2:After downloading the docker installer, then install it. Now to run any docker containers(eg: Redis, MongoDB, PostgreSQL, etc) this docker instance we just installed should be active(should be running).
Step3:Now we need to pull the docker Redis image from the docker hub "https://hub.docker.com/_/redis".
Command To Pull Redis Image:
docker pull redis
Step4:The final step to run the docker Redis image container by mapping our local system port. By default, the Redis instance runs with the '6379' default port inside of the docker container. So to access the Redis we need to port mapping on starting off the container.
Command To Start Redis Container:
docker run --name your_containerName -p your_PortNumber:6379 -d redis
The '--name your_containerName' flag to specify the Redis container name. The '-p your_PortNumber:6379' mapping the Redis port '6379' to our local machine port all our application will use local machine port to communicate with Redis. The '-d' flag represents to run the container in the detached mode which means run in the background. At the last of the command 'redis' to specify the image to run in our container.Step5:
After creating a docker container, it will be stored in our local machine so to start again the container any time run the following command
docker start your_container_name
Let test our Redis instance
Command To Use Redis CLI
docker exec -it your_docker_container_name redis-cli
Create .Net5 Or .NetCore Sample Web API Application:
Let's begin coding to understand Redis cache integration by creating a sample Web API application. The IDE for development is an individual choice but the most recommended are Visual Studio 2019 and Visual Studio Code.
Redis NuGet Packages:
Package Manager Commands:(Visual Studio)
Install-Package StackExchange.Redis.Extensions.AspNetCore
Install-Package StackExchange.Redis.Extensions.Newtonsoft
.Net CLI Commands:(Visual Studo Code)
dotnet add packages StackExchange.Redis.Extensions.AspNetCore
dotnet add packages StackExchange.Redis.Extensions.Newtonsoft
Add Redis JSON Configuration:
All redis settings to communicate with redis store are going to add in appsettings file.
appsettings.Development.json:
"Redis": { "Password": "", "AllowAdmin": false, "Ssl": false, "ConnectTimeout": 6000, "ConnectRetry": 2, "Hosts": [ { "Host": "localhost", "Port": "5003" } ], "Database": 0 }Password - The password for your Redis instance if have(For Production always create a password).
AllowAdmin - The AllowAdmin permissions.
Ssl - The Ssl boolean property to define the communication protocol.
ConnectTimeout - Specify the Redis ConnectionTimeout in milliseconds
ConnectRetry - Number attempts to retry to setup initial connection.
Hosts - Contains a list of Redis instances hostname and port number.
Database- Defining database to communicate, it names are in integers.
Register AddStackExchangeRedisExtensions Service:
Now register register AddStackExchangeRedisExtension in startup file.
Startup.cs:
services.AddStackExchangeRedisExtensions<NewtonsoftSerializer>((options) => { return Configuration.GetSection("Redis").Get<RedisConfiguration>(); });
- Registered Redis extension serializer with 'StackExchange.Redis.Extensions.Newtonsoft.NewtonsoftSerializer'
- Fetching 'Redis' JSON configuration and creating as an instance of type 'StackExchange.Redis.Extensions.Core.Confiugration.ReditConfigurtion'.
Inject IRedisCacheClient:
The 'StackExchange.Redis.Extensions.Core.Abstractions.IRedisCacheClient' provides us Redis context. Using this 'IRedisCacheClient' we have the ability to query, save, filter, delete operations on Redis Store.
Let's create a 'TestController' and then inject the 'IRedisCacheClient' interface.
Controllers/TestController.cs:
using StackExchange.Redis.Extensions.Core.Abstractions; namespace stackexchangeExtension.redis.sample.Controllers { [ApiController] [Route("[controller]")] public class TestController : ControllerBase { private readonly IRedisCacheClient _redisCacheClient; public TestController(IRedisCacheClient redisCacheClient) { _redisCacheClient = redisCacheClient; } } }
AddAsync And GetAsync:
The 'IRedisCacheClient' provides method like 'AddAsync' and 'GetAsync'. The 'AddAsync' method for saving data to Redis store, this can store a simple string type or a complex object type(serialized objects implicitly before saving) and it also provides an option to specify an expiration time for the record in Redis store. The 'GetAsync' method fetches the data from the store with respect to the key we provide, it also provides flexibility to define the type of object for the result, after successfully receiving the result string this method will typecast the result to the type defined.
Controllers/TestController.cs:
[HttpGet] [Route("get-set-cache")] public async Task<IActionResult> GetSetCache() { await _redisCacheClient.GetDbFromConfiguration().AddAsync<string>("myName", "naveen",DateTimeOffset.Now.AddMinutes(2)); return Ok(await _redisCacheClient.GetDbFromConfiguration().GetAsync<string>("myName")); }
- (Line: 5) Saving string data to Redis store and specified the expiration for the record.
- (Line: 6) Fetching string data from Redis store
- The 'GetDbFromConfiguration' pics the Redis database value from our JSON configuration.
Models/Student.cs:
namespace stackexchangeExtension.redis.sample.Models { public class Student { public int Id { get; set; } public string Name { get; set; } public ContactDetails ContactDetails { get; set; } } public class ContactDetails { public string Email { get; set; } public string Phone { get; set; } } }Controllers/TestController.cs:
[HttpGet] [Route("get-set-type-cache")] public async Task<IActionResult> GetSetObjectCach() { var student = new Student{ Id = 1, Name = "naveen", ContactDetails = new ContactDetails{ Email = "naveen@gmail.com", Phone = "1234567890" } }; await _redisCacheClient.GetDbFromConfiguration().AddAsync<Student>("my_student", student, DateTimeOffset.Now.AddHours(1)); return Ok(await _redisCacheClient.GetDbFromConfiguration().GetAsync<Student>("my_student")); }
- (Line: 13) Here we passed directly object as an input parameter. The 'AddAsync()' method serializes our object implicitly before saving it to the Redis store.
- (Line: 14) Here fetches string value from the Redis store but typecast the string value to type we specified by the 'GetAsync' method.
AddAllAsync And GetAllAsync:
The 'AddAllAsync' method can save multiple objects of the same type as multiple records in the Redis store with a single call which gives performance benefits. The 'GetAllAsync' method takes collection keys whose value type same will be fetched from the Redis store with a single Redis call which also gives performance benefits.
Controllers/TestController.cs:
[HttpGet] [Route("get-set-multi-cache")] public async Task<IActionResult> GetSetListCache() { var contact1 = new ContactDetails{ Email = "naveen@gmail.com", Phone = "1234567890" }; var contact2 = new ContactDetails{ Email = "hemanth@gmail.com", Phone = "0987654321" }; var itemsToCache = new List<Tuple<string, ContactDetails>>(); itemsToCache.Add(new Tuple<string, ContactDetails>("contact_1", contact1)); itemsToCache.Add(new Tuple<string, ContactDetails>("contact_2", contact2)); await _redisCacheClient.GetDbFromConfiguration().AddAllAsync(itemsToCache, DateTimeOffset.Now.AddHours(1)); var dataFromCache = await _redisCacheClient.GetDbFromConfiguration().GetAllAsync<ContactDetails>(new List<string>{"contact_1","contact_2"}); return Ok(dataFromCache); }
- (Line: 15-16) Creating a collection of records to be saved to the Redis store.
- (Line: 18) The 'AddAllAsync' method inserts each item in the collection of its input parameter into the Redis store as an individual record one time contacting the Redis store.
- (Line: 20)The 'GetAllAsync' method fetches a collection of Redis records within a single call with respect to the collection ok keys passed to it.
SearchKeysAsync:
The 'SearchKeysAsync' method fetches all the Redis store keys that are matched with the pattern specified to the method.
Controllers/TestController.cs:
[HttpGet] [Route("search-cache-keys")] public async Task<IActionResult> SearchKeys() { // _redisCacheClient.GetDbFromConfiguration().SearchKeysAsync("*con*") var allKeys = (await _redisCacheClient.GetDbFromConfiguration().SearchKeysAsync("*")).ToList(); return Ok(allKeys); }
- (Line: 6) For the 'SearchKeysAsync' method given pattern "*" which means match any letter, so this fetches all keys from the Redis store.
- (Line: 5) The pattern "*con*" means matches the key that contains the string "con" and can contain any prefix and postfix string(eg: keywords like 'bbbconbb', 'conb', etc).
RemoveAsync And RemoveAllAsync:
The 'RemoveAsync' method removes the record from the Redis store with respect to the key passed.
Controllers/TestController.cs:
[HttpGet] [Route("remove")] public async Task<IActionResult> Remove() { await _redisCacheClient.GetDbFromConfiguration().RemoveAsync("test"); return Ok(); }The 'RemoveAllAsync' method is a performance booster method that removes the collection of Redis records in a single Redis call with respect to the collection keys passed as its parameters.
Controllers/TestController.cs:
[HttpGet] [Route("remove-multiple")] public async Task<IActionResult> RemoveMultiple() { var allKeys = (await _redisCacheClient.GetDbFromConfiguration().SearchKeysAsync("contact*")).ToList(); await _redisCacheClient.GetDbFromConfiguration().RemoveAllAsync(allKeys); return Ok(); }
- Here fetching the pattern matching collection of keys and clearing those records using the 'RemoveAllAsync' method.
FlushDbAsync:
Clears all records from the Redis store database.
Controllers/TestController.cs:
[HttpGet] [Route("clear")] public async Task<IActionResult> Clear() { await _redisCacheClient.GetDbFromConfiguration().FlushDbAsync(); return Ok(); }That's all about some of the useful methods of StackExchange.Redis.Extensions library.
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Wrapping Up:
Hopefully, I think this article delivered some useful information on setting up a Redis instance using docker and then consuming the Redis cache into our API application using 'StackeExchange.RedisExtensions' library. I love to have your feedback, suggestions, and better techniques in the comment section below.
How can we do thread safe operations with StackExchange.Redis.Extensions.ApsNetCore ?
ReplyDeleteFor example increment of some integer on some object, or setting some string property on the object?
Thank you very much. It helped me understand the concept.
ReplyDeleteThanks for the article! Small typo APSNetCore
ReplyDeleteInstall-Package StackExchange.Redis.Extensions.ApsNetCore
Thank you corrected now
DeleteI still see ApsNetCore (instead of AspNetCore, I copy-pasted it and package manager did not find it) :)
DeleteOne more thing - as I see from the sources, we can inject IRedisDatabase, not to call GetDbFromConfiguration every time:
ReplyDeletehttps://github.com/imperugo/StackExchange.Redis.Extensions/blob/master/src/aspnet/StackExchange.Redis.Extensions.AspNetCore/Extensions/IServiceCollectionExtensions.cs
Could you please provide me source code for .net 6.0 and Redis cache integration.
ReplyDeleteI need to add Redis Sets and Hashes.
How can we integrate Sliding Expiry ?
ReplyDelete