Serve a temporary html page while tljh is building

2025-12-18 21:54:05 +08:00 · 2020-07-30 22:59:56 +03:00
parent e8136c06c3
commit 972b15b95a
3 changed files with 114 additions and 1 deletions
--- a/bootstrap/bootstrap.py
+++ b/bootstrap/bootstrap.py
@@ -13,10 +13,13 @@ Constraints:
  - Use stdlib modules only
 """
 import os
+from http.server import SimpleHTTPRequestHandler, HTTPServer
+import multiprocessing
 import subprocess
 import sys
 import logging
 import shutil
+import urllib.request

 logger = logging.getLogger(__name__)

@@ -90,7 +93,38 @@ def validate_host():
            print("For local development, see http://tljh.jupyter.org/en/latest/contributing/dev-setup.html")
        sys.exit(1)

+class LoaderPageRequestHandler(SimpleHTTPRequestHandler):
+    def do_GET(self):
+        if self.path == "/logs":
+            with open("/opt/tljh/installer.log", "rb") as log_file:
+                content = log_file.read()
+                self.wfile.write(content)
+        else:
+            self.path = '/index.html'
+            return SimpleHTTPRequestHandler.do_GET(self)
+
+def serve_forever(server):
+    try:
+        server.serve_forever()
+    except KeyboardInterrupt:
+        pass
+
 def main():
+    # Serve the loading page until TLJH builds
+    url="https://raw.githubusercontent.com/jupyterhub/the-littlest-jupyterhub/master/bootstrap/index.html"
+    urllib.request.urlretrieve(url, "index.html")
+
+    # If the bootstrap is run to upgrade TLJH, then this will raise an "Address already in use" error
+    try:
+        loading_page_server = HTTPServer(("", 80), LoaderPageRequestHandler)
+        p = multiprocessing.Process(target=serve_forever, args=(loading_page_server,))
+        p.start()
+        with open('/loading.pid', 'w+') as f:
+            f.write(str(p.pid))
+    except OSError:
+        # Only serve the loading page when installing TLJH
+        pass
+
    validate_host()
    install_prefix = os.environ.get('TLJH_INSTALL_PREFIX', '/opt/tljh')
    hub_prefix = os.path.join(install_prefix, 'hub')
@@ -178,6 +212,5 @@ def main():
        ] + sys.argv[1:]
    )

-
 if __name__ == '__main__':
    main()
--- a/bootstrap/index.html
+++ b/bootstrap/index.html
@@ -0,0 +1,67 @@
+<!DOCTYPE html>
+<html lang="en-US">
+<head>
+  <body>
+    <meta http-equiv="refresh" content="20"/>
+    <img style="width: 150px; height: auto;" src="https://raw.githubusercontent.com/jupyterhub/the-littlest-jupyterhub/master/docs/images/logo/logo.png">
+    <div class="loader"></div>
+    <div class="message">Please wait while your TLJH is building...</div>
+    <div class="logs_info">Click the button below to see the logs</div>
+    <button class="logs_button" onclick="window.location.href='/logs'">View logs</button>
+  </body>
+
+  <style>
+    button:hover {
+      background: grey;
+    }
+
+    .message {
+      position: absolute;
+      top: 35%;
+      left: 30%;
+      font-size: 30px;
+      font-weight: bold;
+      color: grey;
+     }
+
+    .loader {
+      position: absolute;
+      top: 11%;
+      left: 46%;
+      width: 150px;
+      height: 150px;
+      border-radius: 90%;
+      border: 7px solid transparent;
+      animation: spin 2s infinite ease;
+      animation-direction: alternate; 
+    }
+    @keyframes spin {
+      0% {
+        transform: rotateZ(0deg);
+        border-top-color: #f17c0e
+      }
+      100% {
+        transform: rotateZ(360deg);
+        border-top-color: #fce5cf;
+      }
+    }
+    .logs_info {
+      position: absolute;
+      top: 45%;
+      left: 42%;
+      font-size: 15px;
+      color: grey;
+     }
+    .logs_button {
+      position: absolute;
+      top: 50%;
+      left: 46%;
+      border: 0;
+      color: white;
+      padding: 15px 32px;
+      font-size: 16px;
+      cursor: pointer;
+      background: #f5a252;
+    }
+  </style>
+</head>
--- a/tljh/installer.py
+++ b/tljh/installer.py
@@ -6,6 +6,7 @@ import itertools
 import logging
 import os
 import secrets
+import signal
 import subprocess
 import sys
 import time
@@ -499,6 +500,18 @@ def main():
    ensure_node()
    ensure_jupyterhub_package(HUB_ENV_PREFIX)
    ensure_jupyterlab_extensions()
+
+    # Stop the http server with the loading page before traefik starts
+    try:
+        with open(pidfile, "r") as f:
+            pid = f.read()
+        os.kill(int(pid), signal.SIGINT)
+        # Remove the pid file and the temporary html page
+        os.remove('/loading.pid')
+        os.remove('/index.html')
+    except:
+        pass
+
    ensure_jupyterhub_service(HUB_ENV_PREFIX)
    ensure_jupyterhub_running()
    ensure_symlinks(HUB_ENV_PREFIX)