A quick example of Deno.serve

deno-jupyter-test.ipynb

{
 "cells": [
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "# Deno.serve Example\n",
    "\n",
    "Testing out whether I can run `Deno.serve` in a Jupyter notebook."
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 3,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "{ deno: \u001b[32m\"1.44.4+3324d72\"\u001b[39m, v8: \u001b[32m\"12.7.224.9\"\u001b[39m, typescript: \u001b[32m\"5.4.5\"\u001b[39m }"
      ]
     },
     "execution_count": 3,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "Deno.version"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 1,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "Listening on http://localhost:9999/\n"
     ]
    }
   ],
   "source": [
    "let server = Deno.serve({ port: 9999, hostname: \"0.0.0.0\" }, (req: Request) => {\n",
    "    return new Response(\"Hello world\");\n",
    "});"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "This seems to work fine:"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 11,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "Response {\n",
      "  body: ReadableStream { locked: false },\n",
      "  bodyUsed: false,\n",
      "  headers: Headers {\n",
      "    \"content-length\": \"11\",\n",
      "    \"content-type\": \"text/plain;charset=UTF-8\",\n",
      "    date: \"Wed, 03 Jul 2024 05:19:16 GMT\",\n",
      "    vary: \"Accept-Encoding\"\n",
      "  },\n",
      "  ok: true,\n",
      "  redirected: false,\n",
      "  status: 200,\n",
      "  statusText: \"OK\",\n",
      "  url: \"http://localhost:9999/\"\n",
      "}\n"
     ]
    }
   ],
   "source": [
    "let resp = await fetch('http://localhost:9999');\n",
    "console.log(resp);"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "This seems to work, too, oddly:"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 12,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "Hello world\n"
     ]
    }
   ],
   "source": [
    "const command = new Deno.Command(\"curl\", {\n",
    "    args: [\"-v\", \"localhost:9999\"]\n",
    "});\n",
    "\n",
    "const { stdout } = await command.output();\n",
    "console.log(new TextDecoder().decode(stdout));"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "But if I run the following in a shell\n",
    "```sh\n",
    "curl -v localhost:9999\n",
    "```\n",
    "It just hangs\n",
    "```sh\n",
    "*   Trying 127.0.0.1:9999...\n",
    "* Connected to localhost (127.0.0.1) port 9999 (#0)\n",
    "> GET / HTTP/1.1\n",
    "> Host: localhost:9999\n",
    "> User-Agent: curl/7.81.0\n",
    "> Accept: */*\n",
    "> \n",
    "```"
   ]
  }
 ],
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   "display_name": "Deno (Canary)",
   "language": "typescript",
   "name": "deno-canary"
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  "language_info": {
   "codemirror_mode": "typescript",
   "file_extension": ".ts",
   "mimetype": "text/x.typescript",
   "name": "typescript",
   "nbconvert_exporter": "script",
   "pygments_lexer": "typescript",
   "version": "5.4.5"
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