Server Sent Events

Use SendSseUpgrade() to upgrade the connection to server sent events.

routes.Route{Pattern: "GET /sse", Handler: handlers.Welcome}

lib/handlers/welcome.go

package handlers

import (
    "github.com/razshare/frizzante/connections"
    "time"
)

func Welcome(connection *connections.Connection) {
    alive := connection.IsAlive()         // Tracks request status.
    ev := connection.SendSseUpgrade()     // Sends sse upgrade.
    for *alive {                          // Loops until cancellation.
        ev("channel-1")                   // Switches to "channel-1".
        connection.SendMessage("hello 1") // Sends message.
        ev("channel-2")                   // Switches to "channel-2".
        connection.SendMessage("hello 2") // Sends message.
        time.Sleep(time.Second)           // Sleeps for 1 second.
    }
}

Then consume the stream on the client.

<script lang="ts">
    import {source} from "$frizzante/scripts/source.ts";
    const connection = source("/sse")         // Connects to the handler.
    const c1 = connection.select("channel-1") // Listens to "channel-1".
    const c2 = connection.select("channel-2") // Listens to "channel-2".
</script>

<h1>Channel 1</h1>
<span>{$c1}</span>                            <!-- Renders the most recent value of channel-1. -->

<h1>Channel 2</h1>
<span>{$c2}</span>                            <!-- Renders the most recent value of channel-2. -->