oak.localhost

main.ts

import { Application, Router } from "https://deno.land/x/oak/mod.ts";

const app = new Application();
const router = new Router();

// Route to serve index.html
router.get("/", async (context) => {
  try {
    const indexHtml = await Deno.readTextFile("./index.html");
    context.response.headers.set("Content-Type", "text/html");
    context.response.body = indexHtml;
  } catch (error) {
    context.response.status = 500;
    context.response.body = "Error loading index.html";
  }
});

// Route for server-sent events (SSE)
router.get("/sse", async (context) => {
  const upstreamResponse = await fetch("http://localhost:3033?follow");

  if (!upstreamResponse.body) {
    context.response.status = 500;
    context.response.body = "Failed to read response stream";
    return;
  }

  const reader = upstreamResponse.body.getReader();
  const encoder = new TextEncoder();

  context.respond = false; // Disable default Oak response handling

  const body = new ReadableStream({
    async start(controller) {
      try {
        while (true) {
          const { done, value } = await reader.read();
          if (done) break;

          const text = new TextDecoder().decode(value);
          const lines = text.split("\n");

          for (const line of lines) {
            if (line.trim()) {
              controller.enqueue(encoder.encode(`data: ${line}\n\n`));
            }
          }
        }
      } catch (error) {
        controller.error(error);
      } finally {
        controller.close();
        reader.releaseLock();
      }
    },
  });

  context.response.headers.set("Content-Type", "text/event-stream");
  context.response.headers.set("Cache-Control", "no-cache");
  context.response.headers.set("Connection", "keep-alive");
  context.response.body = body;
});

// Dynamic route for :name
router.get("/:name", (context) => {
  const name = context.params.name;
  context.response.body = `Hello, ${name}!`;
});

// Use the router middleware
app.use(router.routes());
app.use(router.allowedMethods());

export default app;