P
Prisma•2w ago
adam boukhris

Sveltekit not receiving real-time data

Hello devs , i was trying to add real time events in my sveltekit app and with the release of prisma pulse and prisma postgreSQL so i added these features to my app but i had problem with prisma pulse , when i create a new DB i receive events when a change happens only in a short period of time and it stops working and i'm not having any error , in my pluse dashboard it says Replication slot status Unavailable idk if it means something , and this is my code , it will be nice of you if you take a look maybe i was doing things not in the right way 
//api/+server.js
import { prisma } from "$lib/index.js";

export async function GET({ request }) {
  const stream = new ReadableStream({
    async start(controller) {
      async function main() {
        try {
          const prismaStream = await prisma.links.stream();

          for await (const event of prismaStream) {
            console.log("Received event:", event);
            controller.enqueue(`data: ${JSON.stringify(event)}\n\n`);
          }
        } catch (error) {
          console.error("Error in Prisma stream:", error);
          controller.error(error);
        }
      }

      main();
    },
    cancel() {
      console.log("Stream cancelled");
    },
  });

  return new Response(stream, {
    headers: {
      "Content-Type": "text/event-stream",
      "Cache-Control": "no-cache",
      Connection: "keep-alive",
      "Access-Control-Allow-Origin": "*",
    },
  });
}
//api/+server.js
import { prisma } from "$lib/index.js";

export async function GET({ request }) {
  const stream = new ReadableStream({
    async start(controller) {
      async function main() {
        try {
          const prismaStream = await prisma.links.stream();

          for await (const event of prismaStream) {
            console.log("Received event:", event);
            controller.enqueue(`data: ${JSON.stringify(event)}\n\n`);
          }
        } catch (error) {
          console.error("Error in Prisma stream:", error);
          controller.error(error);
        }
      }

      main();
    },
    cancel() {
      console.log("Stream cancelled");
    },
  });

  return new Response(stream, {
    headers: {
      "Content-Type": "text/event-stream",
      "Cache-Control": "no-cache",
      Connection: "keep-alive",
      "Access-Control-Allow-Origin": "*",
    },
  });
}
// lib/index.js
import { PrismaClient } from "@prisma/client";
import { withPulse } from "@prisma/extension-pulse";
import { PULSE_API_KEY } from "$env/static/private";

if (!PULSE_API_KEY) {
  throw new Error("PULSE_API_KEY environment variable is not set");
}

const prisma = new PrismaClient().$extends(
  withPulse({
    apiKey: PULSE_API_KEY,
    // Add retry options for better reliability
    retry: {
      maxRetries: 3,
      initialDelay: 1000, // 1 second
    },
  })
);

export { prisma };
// lib/index.js
import { PrismaClient } from "@prisma/client";
import { withPulse } from "@prisma/extension-pulse";
import { PULSE_API_KEY } from "$env/static/private";

if (!PULSE_API_KEY) {
  throw new Error("PULSE_API_KEY environment variable is not set");
}

const prisma = new PrismaClient().$extends(
  withPulse({
    apiKey: PULSE_API_KEY,
    // Add retry options for better reliability
    retry: {
      maxRetries: 3,
      initialDelay: 1000, // 1 second
    },
  })
);

export { prisma };
3 Replies
adam boukhris
adam boukhrisOP•2w ago
//+page.svelte
<script>
  import { onMount } from "svelte";
  export let data;
  let { links } = data;

  onMount(() => {
    const eventSource = new EventSource("/api");

    eventSource.onmessage = (event) => {
      console.log("SSE message received:", event.data);
      const eventData = JSON.parse(event.data);

      switch (eventData.action) {
        case "create":
          links = [...links, eventData.created];
          break;
        case "update":
          links = links.map((link) =>
            link.id === eventData.updated.id ? eventData.updated : link
          );
          break;
        case "delete":
          links = links.filter((link) => link.id !== eventData.deleted.id);
          break;
      }
    };

    eventSource.onerror = (error) => {
      console.error("SSE error:", error);
    };

    return () => {
      eventSource.close();
    };
  });
  const delet = async (id) => {
    const response = await fetch(`/api/delete/${id}`, {
      method: "DELETE",
    });

    if (response.ok) {
      links = links.filter((link) => link.id !== id);
    }
  };
</script>
//+page.svelte
<script>
  import { onMount } from "svelte";
  export let data;
  let { links } = data;

  onMount(() => {
    const eventSource = new EventSource("/api");

    eventSource.onmessage = (event) => {
      console.log("SSE message received:", event.data);
      const eventData = JSON.parse(event.data);

      switch (eventData.action) {
        case "create":
          links = [...links, eventData.created];
          break;
        case "update":
          links = links.map((link) =>
            link.id === eventData.updated.id ? eventData.updated : link
          );
          break;
        case "delete":
          links = links.filter((link) => link.id !== eventData.deleted.id);
          break;
      }
    };

    eventSource.onerror = (error) => {
      console.error("SSE error:", error);
    };

    return () => {
      eventSource.close();
    };
  });
  const delet = async (id) => {
    const response = await fetch(`/api/delete/${id}`, {
      method: "DELETE",
    });

    if (response.ok) {
      links = links.filter((link) => link.id !== id);
    }
  };
</script>
RaphaelEtim
RaphaelEtim•2w ago
Hi @adam boukhris Can you try to re-enable the replication slot? Without the replication slot available, Prisma Pulse cannot stream changes from your DB.
adam boukhris
adam boukhrisOP•2w ago
what do you mean by re-enable the replication i didnt find how in the settings , also when i created a new project it worked for a short period then stopped , even with Replication slot status Unavailable I made some researchs and i found that i have to write sql for this , but i'm using prisma DB so i don't have this access

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