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a Deno port of node-signalr

deno-signalr

A SignalR client for Deno

  • ✅ Supports ASP.net
  • ✅ Written in TypeScript
  • ✅ Supports custom queries and headers
  • ✅ Lots of TSDoc integration
  • ✅ Asynchronous
  • ❌ Does not support ASP.net Core

Credits

License

MIT

Dependencies

  • Evt
    • Used for Event Emitters
  • Custom Socket
    • Used for custom headers on WebSockets

Documentation

NOTICE: This documentation is as of v0.3, usage may change drastically as it reaches v1

Importing

As like any other 3rd-party Deno module, it can be imported with the import statement to the mod.ts URL.

import * as SignalR from "https://deno.land/x/deno_signalr/mod.ts";

Creating a client

Assuming that it has already been imported:

const MyClient = new SignalR.Client("https://localhost:8080/signalr", [ "MyTestHub" ], { 
    query: {
        MyOptionalQuery: "MyOptionalQueryValue"
    },
    headers: {
        MyOptionalHeader: "MyOptionalHeaderValue"
    },
    callTimeout: 5000,
    reconnectDelayTime: 5000
});

This will create a new SignalR client instance with the parameters given.

new Client(string endpoint, Array<string> hubs[, ClientOptions options])

The ClientOptions interface is the following:

export interface ClientOptions {
    /**
     * The queries to add to the URL
     */
    query?: Record<string, unknown>,
    /**
     * The headers for all requests
     */
    headers?: Record<string, string>,
    /**
     * The timeout for calls in milliseconds
     */
    callTimeout?: number,
    /**
     * The delay time for reconnecting in milliseconds
     */
    reconnectDelayTime?: number
}

Configuring a client

After creating the client, it can still be configured:

// Custom headers
MyClient.headers["MyOptionalHeader"] = "nyOptionalVHeaderValue";
// Custom query
MyClient.query["MyOptionalQuery"] = "MyOptionalQueryValue";
// Timeout for sending messages
MyClient.callTimeout = 10000; // 10s, default: 5000ms (5s)
// Delay time for reconnecting
MyClient.reconnectDelayTime = 2000; // 2s, default: 5000ms (5s)

Binding client events

deno-signalr takes advantage of the Evt module, which Client extends:

// Attach until dettached
// MyClient.$attach(SignalR.to(eventName), callback);
// Attach and then dettach after one time
// MyClient.$attachOnce(SignalR.to(eventName), callback);
MyClient.$attach(SignalR.to("connected", () => {
    console.log("SignalR in Deno Example: Connected");
}));
MyClient.$attach(SignalR.to("reconnecting", (connectionCount: number) => {
    console.log(`SignalR in Deno Example: Connecting... ${connectionCount} tries`);
}));
MyClient.$attach(SignalR.to("disconnected", (reason: string) => {
    console.log(`SignalR in Deno Example: Disconnected, reason "${reason}"`);
}));
MyClient.$attach(SignalR.to("error", (error: SignalR.StandardError) => {
    console.log(`SignalR in Deno Example: Error, code: ${error.code}, message: ${typeof(error.message) === "string" ? error.message : "none"}`);
}));

Binding a hub method

Bind callback to receive messages

MyClient.connection.hub.on("MyHub", "MyMethod", (message: unknown) => {
    console.log(`SignalR in Deno Example: New message from MyHub/MyMethod: ${message.toString()}`);
});

void Hub.on(string hub, string method, function callback)

Call the method and return the values asynchronously

MyClient.connection.hub.call("MyHub", "MyMethod", "hi from SignalR in Deno!").then((result: boolean) => {
    console.log(`SignalR in Deno Example: Sent message to MyHub/MyMethod success: ${result.toString()}`);
});

Promise<unknown> Hub.call(string hub, string method, unknown message)

Invoke the method without return values

MyClient.connection.hub.invoke("MyHub", "MyMethod", "hi from SignalR in Deno!");

void Hub.invoke(string hub, string method, unknown message)

Starting the connection

When ready to start the connection to the Hubs, start the client:

MyClient.start();

This will negotiate, start and connect with the hubs.

void Client.start(number protocol = 1.5)

Ending the connection

When no longer needed, end the connection (if it exists):

MyClient.end()

void Client.end()