. How the core in net uses Redis to publish subscriptions for instance analysis

This article mainly describes how the. NET Core uses the Redis publishing subscription, the small part feels quite good, now shares to everybody, also gives everybody to make a reference. Let's take a look at it with a little knitting.

Redis is a very powerful memory database that is typically used as a cache, but not just as a cache, such as the well-known distributed framework Dubbo can use Redis as a service registry. Next, let's introduce the Publish/subscribe feature of. NET core using Redis.

Redis Publish Subscriptions

A Redis Publish Subscription (PUB/SUB) is a message communication pattern: the Sender (pub) sends a message and the Subscriber (sub) receives the message.
Redis clients can subscribe to any number of channels.

Shows the relationship between channel Channel1 and the three client--client2, CLIENT5, and client1 subscribing to this channel:

When a new message is sent to channel Channel1 via the PUBLISH command, the message is sent to the three clients subscribed to it:

Using Redis commands

First, two clients are subscribed to the Redismessage channel via the Subscribe redismessage command:

Then open a Redis client and use the command publish Redismessage "message content" to publish the message

Using the. NET Core implementation

Here I choose the connection drive for Stackexchange.redis, here to note is Servicestack.redis connection drivers have become commercially available, with restrictions of 4.0 and later, so choose from a free and easy-to-use Stackexchange.redis, using NuGet to install.

Establishing a subscription client

Create connection using (connectionmultiplexer Redis = Connectionmultiplexer.connect ("127.0.0.1:6379")) {  Isubscriber sub = Redis. Getsubscriber ();  Subscribe to a channel sub named messages  . Subscribe ("Messages", (channel, message) = {    //output received message    Console.WriteLine ($ "[{DATETIME.NOW:HH:MM:SS}] { Message} ");  Console.WriteLine ("Subscribed to Messages");  Console.readkey ();}

Build a publishing client

Create connection using (connectionmultiplexer Redis = Connectionmultiplexer.connect ("127.0.0.1:6379")) {  Isubscriber sub = Redis. Getsubscriber ();  Console.WriteLine ("Please enter any characters, enter exit Exit");  string input;  Do  {    input = Console.ReadLine ();    Sub. Publish ("Messages", input);  } while (Input! = "Exit");}

The following runs a publishing client with two subscription clients: