Add javascript to 404 page that redirects all /live/... urls to the playtorch.dev website

justinhaaheim · justinhaaheim · commit ee6cdd5a89fe · 2022-07-22T11:08:39.000-07:00
diff --git a/404.html b/404.html
@@ -7,6 +7,66 @@
 
 <!DOCTYPE html>
 <html>
+  <head>
+    <script type="text/javascript" charset="utf-8">
+      // const FALLBACK_URL = 'https://opensource.fb.com';
+      const REDIRECT_STYLE = {
+        // Redirect completely, appending the path to the newly specified location.
+        // This is useful for project renames or moving to a different org.
+        FULL: 0,
+        // Redirect to the specific location, losing path information
+        // This is useful when you just want to capture the audience to known working page.
+        SIMPLE: 1,
+        // Redirect to the project's 404 page, injecting the original URL.
+        FOUROHFOUR_DEFAULT: 2,
+        // Redirect to the specified path, replacing ${from} with the original URL.
+        FOUROHFOUR_CUSTOM: 3,
+      };
+
+      const PROJECTS = {
+        live: {
+          location: 'https://playtorch.dev/',
+          style: REDIRECT_STYLE.FULL,
+        },
+      };
+
+      // eg "https://facebook.github.io/flux/docs/overview/"
+      const ORIGINAL_URL = window.location.href;
+      // eg [ "", "flux", "docs", "overview", "" ]
+      const PATH_PARTS = window.location.path.split('/');
+      // eg "flux"
+      const PROJECT = PATH_PARTS[1];
+      // eg "docs/overview/"
+      const SUBPATH = PATH_PARTS.slice(2).join('/');
+
+      
+      // Perform the redirect only for explicitly defined projects.
+      // Otherwise show the 404 page below
+      if (PROJECTS.hasOwnProperty(PROJECT)) {
+        let newUrl = '';
+        let project = PROJECTS[PROJECT];
+        switch (project.style) {
+          case REDIRECT_STYLE.FULL:
+            newUrl = project.location + SUBPATH;
+            break;
+          case REDIRECT_STYLE.SIMPLE:
+            newUrl = project.location;
+            break;
+          case REDIRECT_STYLE.FOUROHFOUR_DEFAULT:
+            newUrl = project.location + '404.html?from=' + ORIGINAL_URL;
+            break;
+          case REDIRECT_STYLE.FOUROHFOUR_CUSTOM:
+            newUrl = project.location.replace('${from}', ORIGINAL_URL);
+            break;
+          default:
+            newUrl = FALLBACK_URL;
+        }
+
+        window.location.href = newUrl;
+      }
+
+    </script>
+  </head>
 <body>
   <div style="text-align: center;">
     <img src="{{ site.baseurl }}/assets/images/404_sign.png" />
