add simple editor UI and backend

.gitignore

@@ -5,6 +5,10 @@ build/
 __pycache__/
 dist/
 
+node_modules/
+
 .venv/
 venv/
 ttt/
+
+instance/

cloudflare_error_page/__init__.py

@@ -1,3 +1,4 @@
+import html
 import os
 import secrets
 from datetime import datetime, timezone
@@ -18,7 +19,7 @@ def get_resources_folder() -> str:
     return os.path.join(os.path.dirname(os.path.abspath(__file__)), 'resources')
 
 
-def render(params: dict, use_cdn: bool=True) -> str:
+def render(params: dict, allow_html: bool=True, use_cdn: bool=True, show_creator: bool=False) -> str:
     """
     Render a customized Cloudflare error page.
     """
@@ -28,6 +29,9 @@ def render(params: dict, use_cdn: bool=True) -> str:
         params['time'] = utc_now.strftime("%Y-%m-%d %H:%M:%S UTC")
     if not params.get('ray_id'):
         params['ray_id'] = secrets.token_hex(8)
+    if not allow_html:
+        params['what_happened'] = html.escape(params.get('what_happened', ''))
+        params['what_can_i_do'] = html.escape(params.get('what_can_i_do', ''))
 
     template = env.get_template("error.html")
-    return template.render(params=params, resources_use_cdn=use_cdn)
+    return template.render(params=params, resources_use_cdn=use_cdn, show_creator=show_creator)

cloudflare_error_page/templates/error.html

@@ -50,7 +50,7 @@
                         {% set default_name = 'Host' -%}
                     {% endif %}
                     {% set item = params.get(item_id + '_status', {}) -%}
-                    {% set status = item.get('status', 'ok') -%}
+                    {% set status = item.status or 'ok' -%}
                     {% if item.status_text_color %}
                         {% set text_color = item.status_text_color -%}
                     {% elif status == 'ok' %}
@@ -58,7 +58,7 @@
                     {% elif status == 'error' %}
                         {% set text_color = '#bd2426' -%} {# text-red-error #}
                     {% endif %}
-                    {% set status_text = item.get('status_text', 'Working' if status == 'ok' else 'Not Working') -%}
+                    {% set status_text = item.status_text or ('Working' if status == 'ok' else 'Not Working') -%}
                     <div id="cf-{{item_id}}-status" class="{{'cf-error-source' if params.error_source == item_id else ''}} relative w-1/3 md:w-full py-15 md:p-0 md:py-8 md:text-left md:border-solid md:border-0 md:border-b md:border-gray-400 overflow-hidden float-left md:float-none text-center">
                         <div class="relative mb-10 md:m-0">
                             <span class="cf-icon-{{icon}} block md:hidden h-20 bg-center bg-no-repeat"></span>
@@ -96,8 +96,13 @@
                     <span class="hidden" id="cf-footer-ip">{{ params.client_ip or '1.1.1.1' }}</span>
                     <span class="cf-footer-separator sm:hidden">&bull;</span>
                 </span>
-                {% set perf_sec_by = params.get('perf_sec_by', {}) %}
+                {% set perf_sec_by = params.perf_sec_by or {} %}
-                <span class="cf-footer-item sm:block sm:mb-1"><span>Performance &amp; security by</span> <a rel="noopener noreferrer" href="{{perf_sec_by.link or 'https://www.cloudflare.com/'}}" id="brand_link" target="_blank">{{perf_sec_by.get('text', 'Cloudflare')}}</a></span>
+                <span class="cf-footer-item sm:block sm:mb-1"><span>Performance &amp; security by</span> <a rel="noopener noreferrer" href="{{perf_sec_by.link or 'https://www.cloudflare.com/'}}" id="brand_link" target="_blank">{{perf_sec_by.text or 'Cloudflare'}}</a></span>
+
+                {% if show_creator %}
+                <span class="cf-footer-separator sm:hidden">&bull;</span>
+                <span class="cf-footer-item sm:block sm:mb-1">Created by <a href="https://virt.moe/cloudflare-error-page/editor/" target="_blank">CF Error Page Editor</a></span>
+                {% endif %}
             </p>
         </div><!-- /.error-footer -->
     </div>

editor/resources/index.html

@@ -0,0 +1,783 @@
+<!-- SPDX-License-Identifier: MIT -->
+<!--
+!!!
+!!! Note: This file is vibely generated, and could be very hard to maintain.
+!!!
+-->
+<!doctype html>
+<html lang="en">
+
+<head>
+  <meta charset="utf-8" />
+  <meta name="viewport" content="width=device-width,initial-scale=1" />
+  <title>Cloudflare Error Page Editor</title>
+
+  <script src="https://cdn.jsdelivr.net/npm/ejs@3.1.10/ejs.min.js"></script>
+  <link href="https://cdn.jsdelivr.net/npm/bootstrap@5.3.2/dist/css/bootstrap.min.css" rel="stylesheet">
+
+  <script>
+    (async function () {
+      /*
+        Editor logic
+        - initialConfig: provided default config (from your JSON)
+        - render(): placeholder that generates HTML and writes to iframe.srcdoc
+        - inputs call render() on change
+        - "Open in new tab" opens the rendered HTML in a new window using a blob URL
+      */
+      let template;
+      let postponeRendering = false;
+
+      fetch('template.ejs')
+        .then(response => {
+          if (!response.ok) {
+            alert('failed to fetch template');
+          }
+          return response.text(); // Returns a Promise
+        })
+        .then(templateContent => {
+          template = ejs.compile(templateContent)
+          if (postponeRendering) {
+            render()
+          }
+        })
+
+      const initialConfig = {
+        "html_title": "cloudflare.com | 500: Internal server error",
+        "title": "Internal server error",
+        "error_code": 500,
+
+        "more_information": {
+          "hidden": false,
+          "text": "cloudflare.com",
+          "link": "https://youtube.com/watch?v=dQw4w9WgXcQ"
+        },
+
+        "browser_status": {
+          "status": "ok",
+          "location": "You",
+          "name": "Browser",
+          "status_text": "Working"
+        },
+        "cloudflare_status": {
+          "status": "error",
+          "location": "Cloud",
+          "name": "Cloudflare",
+          "status_text": "Not Working"
+        },
+        "host_status": {
+          "status": "ok",
+          "location": "The Site",
+          "name": "Host",
+          "status_text": "Working"
+        },
+        "error_source": "host",
+        "what_happened": "There is an internal server error on Cloudflare's network.",
+        "what_can_i_do": "Please try again in a few minutes.",
+        "perf_sec_by": {
+          "text": "Cloudflare",
+          "link": "https://youtube.com/watch?v=dQw4w9WgXcQ"
+        }
+      };
+
+      // Demo presets (content brief — replace or expand as needed)
+      const PRESETS = {
+        "default": structuredClone(initialConfig),
+        "empty": {
+          "error_code": 500,
+        },
+        "catastrophic": {
+          "title": "Catastrophic infrastructure failure",
+          "error_code": 500,
+          "more_information": {
+            "text": "cloudflare.com",
+            "link": "https://youtube.com/watch?v=dQw4w9WgXcQ"
+          },
+          "browser_status": {
+            "status": "error",
+            "status_text": "Out of Memory"
+          },
+          "cloudflare_status": {
+            "status": "error",
+            "location": "Everywhere",
+            "status_text": "Not Working"
+          },
+          "host_status": {
+            "status": "error",
+            "location": "example.com",
+            "status_text": "On Fire"
+          },
+          "error_source": "cloudflare",
+          "what_happened": "There is a catastrophic failure.",
+          "what_can_i_do": "Please try again in a few years.",
+          "perf_sec_by": {
+            "text": "Cloudflare",
+            "link": "https://youtube.com/watch?v=dQw4w9WgXcQ"
+          }
+        },
+        "working": {
+          "title": "Web server is working",
+          "error_code": 200,
+          "more_information": {
+            "hidden": true
+          },
+          "browser_status": {
+            "status": "ok",
+            "status_text": "Seems Working"
+          },
+          "cloudflare_status": {
+            "status": "ok",
+            "status_text": "Often Working"
+          },
+          "host_status": {
+            "status": "ok",
+            "location": "example.com",
+            "status_text": "Just Working"
+          },
+          "error_source": "host",
+          "what_happened": "This site is still working. And it looks great.",
+          "what_can_i_do": "Visit the site before it crashes someday."
+        },
+      };
+
+      /* Utilities */
+      function $(id) { return document.getElementById(id); }
+
+      /* Fill form from config */
+      function loadConfig(cfg) {
+        $('html_title').value = cfg.html_title ?? '';
+        $('title').value = cfg.title ?? '';
+        $('error_code').value = cfg.error_code ?? '';
+
+        $('more_hidden').checked = !!(cfg.more_information && cfg.more_information.hidden);
+        $('more_text').value = cfg.more_information?.text ?? '';
+        $('more_link').value = cfg.more_information?.link ?? '';
+
+        $('browser_status').value = cfg.browser_status?.status ?? 'ok';
+        $('browser_location').value = cfg.browser_status?.location ?? '';
+        $('browser_name').value = cfg.browser_status?.name ?? '';
+        $('browser_status_text').value = cfg.browser_status?.status_text ?? '';
+
+        $('cloudflare_status').value = cfg.cloudflare_status?.status ?? 'ok';
+        $('cloudflare_location').value = cfg.cloudflare_status?.location ?? '';
+        $('cloudflare_name').value = cfg.cloudflare_status?.name ?? '';
+        $('cloudflare_status_text').value = cfg.cloudflare_status?.status_text ?? '';
+
+        $('host_status').value = cfg.host_status?.status ?? 'ok';
+        $('host_location').value = cfg.host_status?.location ?? '';
+        $('host_name').value = cfg.host_status?.name ?? '';
+        $('host_status_text').value = cfg.host_status?.status_text ?? '';
+
+        if (cfg.error_source === 'browser') $('err_browser').checked = true;
+        else if (cfg.error_source === 'cloudflare') $('err_cloudflare').checked = true;
+        else $('err_host').checked = true;
+
+        $('what_happened').value = cfg.what_happened ?? '';
+        $('what_can_i_do').value = cfg.what_can_i_do ?? '';
+
+        $('perf_text').value = cfg.perf_sec_by?.text ?? '';
+        $('perf_link').value = cfg.perf_sec_by?.link ?? '';
+      }
+
+      /* Read config from form inputs */
+      function readConfig() {
+        return {
+          html_title: $('html_title').value,
+          title: $('title').value,
+          error_code: Number($('error_code').value) || 0,
+          more_information: {
+            hidden: !!$('more_hidden').checked,
+            text: $('more_text').value,
+            link: $('more_link').value
+          },
+          browser_status: {
+            status: $('browser_status').value,
+            location: $('browser_location').value,
+            name: $('browser_name').value,
+            status_text: $('browser_status_text').value
+          },
+          cloudflare_status: {
+            status: $('cloudflare_status').value,
+            location: $('cloudflare_location').value,
+            name: $('cloudflare_name').value,
+            status_text: $('cloudflare_status_text').value
+          },
+          host_status: {
+            status: $('host_status').value,
+            location: $('host_location').value,
+            name: $('host_name').value,
+            status_text: $('host_status_text').value
+          },
+          error_source: (document.querySelector('input[name="error_source"]:checked') || { value: 'host' }).value,
+          what_happened: $('what_happened').value,
+          what_can_i_do: $('what_can_i_do').value,
+          perf_sec_by: {
+            text: $('perf_text').value,
+            link: $('perf_link').value
+          }
+        };
+      }
+      function formatUtcTimestamp() {
+        const d = new Date();
+
+        const year = d.getUTCFullYear();
+        const month = String(d.getUTCMonth() + 1).padStart(2, "0");
+        const day = String(d.getUTCDate()).padStart(2, "0");
+
+        const hours = String(d.getUTCHours()).padStart(2, "0");
+        const minutes = String(d.getUTCMinutes()).padStart(2, "0");
+        const seconds = String(d.getUTCSeconds()).padStart(2, "0");
+
+        return `${year}-${month}-${day} ${hours}:${minutes}:${seconds} UTC`;
+      }
+
+      function renderEjs(params, use_cdn = true) {
+        return template({
+          params: params,
+          resources_use_cdn: use_cdn
+        })
+      }
+
+      /* Basic render: build HTML string from config and put into iframe.srcdoc */
+      function render() {
+        const cfg = readConfig();
+        window.lastCfg = cfg
+
+        if (!template) {
+          postponeRendering = true
+          return
+        }
+
+        cfg.time = formatUtcTimestamp()
+        cfg.ray_id = '0123456789abcdef'
+        cfg.client_ip = '1.1.1.1'
+
+        let pageHtml = renderEjs(cfg)
+        // Write into iframe
+        const iframe = $('previewFrame');
+        iframe.srcdoc = pageHtml;
+
+        // store last rendered HTML for "open in new tab"
+        lastRenderedHtml = pageHtml;
+        updateStatusBlockStyles();
+      }
+
+      /* Open in new tab: create blob and open */
+      let lastRenderedHtml = '';
+      function openInNewTab() {
+        if (!lastRenderedHtml) render();
+        const blob = new Blob([lastRenderedHtml], { type: 'text/html' });
+        const url = URL.createObjectURL(blob);
+        window.open(url, '_blank', 'noopener');
+        // revoke after some time to avoid memory leak
+        setTimeout(() => URL.revokeObjectURL(url), 15_000);
+      }
+
+      function createShareableLink() {
+        $('shareLink').value = ''
+        fetch('../s/create', {
+          method: 'POST',
+          headers: {
+            'Content-Type': 'application/json'
+          },
+          body: JSON.stringify({
+            'parameters': window.lastCfg
+          })
+        })
+          .then(response => {
+            if (!response.ok) {
+              alert('failed to create link');
+            }
+            return response.json();
+          })
+          .then(result => {
+            if (result.status != 'ok') {
+              alert('failed to create link');
+              return
+            }
+            $('shareLink').value = result.url
+          })
+      }
+      function exportJSON() {
+        let content = JSON.stringify(lastCfg)
+        const file = new File([content], 'cloudflare-error-page-params.json', {
+          type: 'text/plain',
+        })
+        const link = document.createElement('a')
+        const url = URL.createObjectURL(file)
+
+        link.href = url
+        link.download = file.name
+        document.body.appendChild(link)
+        link.click()
+
+        document.body.removeChild(link)
+        window.URL.revokeObjectURL(url)
+      }
+
+      /* Wire up events */
+      document.addEventListener('DOMContentLoaded', () => {
+        // initialize form values from initialConfig
+        loadConfig(initialConfig);
+        render();
+
+        // On preset change, load preset and render
+        $('presetSelect').addEventListener('change', e => {
+          const p = e.target.value;
+          if (PRESETS[p]) loadConfig(PRESETS[p]);
+          render();
+        });
+
+        // Render / Open button handlers
+        //   $('btnRender').addEventListener('click', e => { e.preventDefault(); render(); });
+        $('btnOpen').addEventListener('click', e => { e.preventDefault(); openInNewTab(); });
+        $('btnShare').addEventListener('click', e => { e.preventDefault(); createShareableLink() });
+        $('btnExport').addEventListener('click', e => { e.preventDefault(); exportJSON() });
+
+        $('btnCopyLink').addEventListener('click', () => {
+          const field = $('shareLink');
+          field.select();
+          field.setSelectionRange(0, field.value.length);
+          navigator.clipboard.writeText(field.value).then(() => {
+            // No notification required unless you want one
+          });
+        });
+
+        // Input change -> render
+        const inputs = document.querySelectorAll('#editorForm input, #editorForm textarea, #editorForm select');
+        inputs.forEach(inp => {
+          inp.addEventListener('input', debounce(() => {
+            // Update status block color classes for quick visual feedback in the editor
+            render();
+          }, 250));
+          // for radio change events (error_source)
+          if (inp.type === 'radio') inp.addEventListener('change', () => { render(); });
+        });
+      });
+
+      /* Update status block colors based on selected status and error_source */
+      function updateStatusBlockStyles() {
+        const browserOk = $('browser_status').value === 'ok';
+        const cfOk = $('cloudflare_status').value === 'ok';
+        const hostOk = $('host_status').value === 'ok';
+
+        setBlockClass('block_browser', browserOk ? 'status-ok' : 'status-error');
+        setBlockClass('block_cloudflare', cfOk ? 'status-ok' : 'status-error');
+        setBlockClass('block_host', hostOk ? 'status-ok' : 'status-error');
+      }
+
+      function setBlockClass(id, cls) {
+        const el = $(id);
+        if (!el) return;
+        el.classList.remove('status-ok', 'status-error');
+        el.classList.add(cls);
+      }
+
+      /* Simple debounce */
+      function debounce(fn, wait) {
+        let t;
+        return (...args) => {
+          clearTimeout(t);
+          t = setTimeout(() => fn(...args), wait);
+        };
+      }
+    })()
+  </script>
+  <style>
+    /* Layout: editor + preview */
+    .app {
+      display: flex;
+      flex-direction: column;
+      gap: 1rem;
+      height: 100vh;
+      padding: 0.8rem;
+    }
+
+    /* On md and up, arrange horizontally: editor left, preview right */
+    @media (min-width: 768px) {
+      .app {
+        flex-direction: row;
+        align-items: stretch;
+      }
+
+      .editor {
+        flex: 0 0;
+        min-width: 380px;
+        overflow-y: auto;
+      }
+
+      .preview {
+        flex: 1 1 48%;
+        /* max-width: 48%; */
+        display: flex;
+        flex-direction: column;
+      }
+    }
+
+    /* On small screens use stacked layout: editor then iframe */
+    .editor {
+      background: #fff;
+      border: 1px solid #e3e6ea;
+      border-radius: .5rem;
+      padding: 0.8rem;
+    }
+
+    .preview {
+      background: #fff;
+      border: 1px solid #e3e6ea;
+      border-radius: .5rem;
+      padding: 0.8rem;
+      min-height: 100%;
+    }
+
+    /* Compact form: label and control same row */
+    .form-row {
+      display: flex;
+      gap: .3rem;
+      align-items: center;
+      margin-bottom: .6rem;
+    }
+
+    .form-row>label {
+      min-width: 6rem;
+      max-width: 12rem;
+      margin-bottom: 0;
+      font-weight: 600;
+    }
+
+    .form-row>.control {
+      flex: 1;
+    }
+
+    /* Status block styling */
+    .status-block {
+      border: 1px solid #cfeadd;
+      border-radius: .375rem;
+      padding: .75rem;
+      margin-bottom: .5rem;
+    }
+
+    .status-ok {
+      background: #e9f7ef;
+      border: 1px solid #cfeadd;
+    }
+
+    .status-error {
+      background: #fff5f5;
+      border: 1px solid #f3c2c2;
+    }
+
+    /* Iframe styling */
+    iframe.preview-frame {
+      width: 100%;
+      height: 100%;
+      border: 1px solid #ddd;
+      flex: 1 1 auto;
+      min-height: 360px;
+      border-radius: .375rem;
+      box-shadow: 0 1px 4px rgba(0, 0, 0, .06);
+    }
+
+    /* Controls toolbar */
+    .toolbar {
+      display: flex;
+      gap: .5rem;
+      align-items: center;
+      justify-content: space-between;
+      margin-bottom: .75rem;
+    }
+
+    /* Compact textarea resizing */
+    textarea.compact {
+      min-height: 80px;
+      resize: vertical;
+    }
+  </style>
+</head>
+
+<body class="bg-light">
+
+  <div class="container-fluid h-100">
+    <div class="app">
+
+      <!-- Editor column -->
+      <div class="editor">
+        <h5 class="form-row">Cloudflare Error Page Editor</h5>
+        <hr>
+        <div class="form-row mb-3">
+          <label for="presetSelect">Preset:</label>
+          <select id="presetSelect" class="form-select form-select-sm">
+            <option value="default">Default</option>
+            <option value="empty">Empty</option>
+            <option value="catastrophic">Catastrophic failure</option>
+            <option value="working">Server working</option>
+          </select>
+        </div>
+
+        <form id="editorForm" class="needs-validation" novalidate>
+          <!-- Basic properties -->
+          <div class="mb-3">
+            <!-- <h6 class="mb-2">Page</h6> -->
+
+            <div class="form-row">
+              <label for="html_title">HTML Title</label>
+              <div class="control">
+                <input id="html_title" class="form-control form-control-sm"
+                  placeholder="cloudflare.com | 500: Internal server error" />
+              </div>
+            </div>
+
+            <div class="form-row">
+              <label for="title">Title</label>
+              <div class="control">
+                <input id="title" class="form-control form-control-sm" placeholder="Internal server error" />
+              </div>
+            </div>
+
+            <div class="form-row">
+              <label for="error_code">Error Code</label>
+              <div class="control">
+                <input id="error_code" type="number" class="form-control form-control-sm" />
+              </div>
+            </div>
+          </div>
+
+          <!-- More information -->
+          <div class="mt-3 mb-3">
+            <h6 class="mb-2">Visit ... for more information</h6>
+
+            <div class="status-block">
+              <div class="form-row">
+                <label>Hidden</label>
+                <div class="control d-flex align-items-center gap-2">
+                  <input id="more_hidden" class="form-check-input" type="checkbox" />
+                  <!-- <small class="text-muted">If checked, the "visit ..." line is hidden</small> -->
+                </div>
+              </div>
+
+              <div class="form-row">
+                <label for="more_text">Text</label>
+                <div class="control">
+                  <input id="more_text" class="form-control form-control-sm" placeholder="cloudflare.com" />
+                </div>
+              </div>
+
+              <div class="form-row">
+                <label for="more_link">Link</label>
+                <div class="control">
+                  <input id="more_link" class="form-control form-control-sm"
+                    placeholder="https://www.cloudflare.com/" />
+                </div>
+              </div>
+            </div>
+          </div>
+
+          <!-- Status blocks -->
+          <div class="mb-3">
+            <h6 class="mb-2">Status</h6>
+
+            <!-- Browser -->
+            <div id="block_browser" class="status-block status-ok">
+              <div class="d-flex justify-content-between align-items-start mb-2">
+                <strong>Browser</strong>
+                <div>
+                  <input class="form-check-input" type="radio" name="error_source" id="err_browser" value="browser" />
+                  <label for="err_browser" class="ms-1 small">Error here</label>
+                </div>
+              </div>
+
+              <div class="form-row">
+                <label for="browser_status">Status</label>
+                <div class="control">
+                  <select id="browser_status" class="form-select form-select-sm">
+                    <option value="ok">Ok</option>
+                    <option value="error">Error</option>
+                  </select>
+                </div>
+              </div>
+
+              <div class="form-row">
+                <label for="browser_location">Location</label>
+                <div class="control">
+                  <input id="browser_location" class="form-control form-control-sm" placeholder="Browser" />
+                </div>
+              </div>
+
+              <div class="form-row">
+                <label for="browser_name">Name</label>
+                <div class="control">
+                  <input id="browser_name" class="form-control form-control-sm" placeholder="You" />
+                </div>
+              </div>
+
+              <div class="form-row">
+                <label for="browser_status_text">Status text</label>
+                <div class="control">
+                  <input id="browser_status_text" class="form-control form-control-sm" />
+                </div>
+              </div>
+            </div>
+
+            <!-- Cloudflare -->
+            <div id="block_cloudflare" class="status-block status-error">
+              <div class="d-flex justify-content-between align-items-start mb-2">
+                <strong>Cloudflare</strong>
+                <div>
+                  <input class="form-check-input" type="radio" name="error_source" id="err_cloudflare"
+                    value="cloudflare" />
+                  <label for="err_cloudflare" class="ms-1 small">Error here</label>
+                </div>
+              </div>
+
+              <div class="form-row">
+                <label for="cloudflare_status">Status</label>
+                <div class="control">
+                  <select id="cloudflare_status" class="form-select form-select-sm">
+                    <option value="ok">Ok</option>
+                    <option value="error">Error</option>
+                  </select>
+                </div>
+              </div>
+
+              <div class="form-row">
+                <label for="cloudflare_location">Location</label>
+                <div class="control">
+                  <input id="cloudflare_location" class="form-control form-control-sm" placeholder="Cloud" />
+                </div>
+              </div>
+
+              <div class="form-row">
+                <label for="cloudflare_name">Name</label>
+                <div class="control">
+                  <input id="cloudflare_name" class="form-control form-control-sm" placeholder="Cloudflare" />
+                </div>
+              </div>
+
+              <div class="form-row">
+                <label for="cloudflare_status_text">Status text</label>
+                <div class="control">
+                  <input id="cloudflare_status_text" class="form-control form-control-sm" />
+                </div>
+              </div>
+            </div>
+
+            <!-- Host -->
+            <div id="block_host" class="status-block status-ok">
+              <div class="d-flex justify-content-between align-items-start mb-2">
+                <strong>Host</strong>
+                <div>
+                  <input class="form-check-input" type="radio" name="error_source" id="err_host" value="host" />
+                  <label for="err_host" class="ms-1 small">Error here</label>
+                </div>
+              </div>
+
+              <div class="form-row">
+                <label for="host_status">Status</label>
+                <div class="control">
+                  <select id="host_status" class="form-select form-select-sm">
+                    <option value="ok">Ok</option>
+                    <option value="error">Error</option>
+                  </select>
+                </div>
+              </div>
+
+              <div class="form-row">
+                <label for="host_location">Location</label>
+                <div class="control">
+                  <input id="host_location" class="form-control form-control-sm" placeholder="The site" />
+                </div>
+              </div>
+
+              <div class="form-row">
+                <label for="host_name">Name</label>
+                <div class="control">
+                  <input id="host_name" class="form-control form-control-sm" placeholder="Host" />
+                </div>
+              </div>
+
+              <div class="form-row">
+                <label for="host_status_text">Status text</label>
+                <div class="control">
+                  <input id="host_status_text" class="form-control form-control-sm" />
+                </div>
+              </div>
+            </div>
+          </div>
+
+          <label for="what_happened" class="fw-semibold">What happened?</label>
+          <div class="control">
+            <textarea id="what_happened" class="form-control compact" placeholder="There is an internal server error on Cloudflare's network.
+"></textarea>
+          </div>
+          <!-- </div> -->
+
+          <!-- <div class=""> -->
+          <label for="what_can_i_do" class="fw-semibold mt-2">What can I do?</label>
+          <div class="control">
+            <textarea id="what_can_i_do" class="form-control compact"
+              placeholder="Please try again in a few minutes."></textarea>
+          </div>
+
+          <hr>
+
+          <h6 class="form-row">Performance & security by ...</h6>
+
+          <div class="form-row">
+            <label for="perf_text">Text</label>
+            <div class="control">
+              <input id="perf_text" class="form-control form-control-sm" placeholder="Cloudflare" />
+            </div>
+          </div>
+
+          <div class="form-row">
+            <label for="perf_link">Link</label>
+            <div class="control">
+              <input id="perf_link" class="form-control form-control-sm" placeholder="https://www.cloudflare.com/" />
+            </div>
+          </div>
+          <!-- </div> -->
+
+          <div class="d-flex gap-2 mt-2 mb-2">
+            <!-- <button id="btnRender" class="btn btn-sm btn-primary">Render</button> -->
+            <button id="btnOpen" class="btn btn-sm btn-primary">Preview in new tab</button>
+            <button id="btnExport" class="btn btn-sm btn-primary">Export JSON</button>
+          </div>
+
+          <button id="btnShare" class="btn btn-sm btn-primary">Create shareable link</button>
+          <div class="mt-2">
+            <div class="input-group input-group-sm">
+              <input id="shareLink" class="form-control" readonly />
+              <button id="btnCopyLink" class="btn btn-outline-secondary" type="button">Copy</button>
+            </div>
+          </div>
+
+          <div class="fw-semibold mt-2 text-center">&gt;&gt; Star this project on
+            <a href="https://github.com/donlon/cloudflare-error-page" target="_blank">Github</a> ⭐
+          </div>
+
+          <div class="mt-2" style="font-size: 0.9em;">You can also embed the error page into your own website. See
+            <a href="https://github.com/donlon/cloudflare-error-page#quickstart" target="_blank">Quickstart</a> in the
+            homepage.
+          </div>
+
+        </form>
+      </div>
+
+      <!-- Preview column -->
+      <div class="preview">
+        <div class="d-flex justify-content-between align-items-center mb-1">
+          <h6><strong>Preview</strong></h6>
+          <div class="text-muted small">Preview updates automatically on change</div>
+        </div>
+
+        <iframe id="previewFrame" class="preview-frame" sandbox="allow-same-origin allow-popups allow-forms"></iframe>
+      </div>
+
+    </div>
+  </div>
+
+  <!-- JS: Bootstrap bundle -->
+  <script src="https://cdn.jsdelivr.net/npm/bootstrap@5.3.2/dist/js/bootstrap.bundle.min.js"></script>
+
+</body>
+
+</html>

editor/resources/template.ejs

@@ -0,0 +1,118 @@
+<%
+let resources_cdn = resources_use_cdn ? 'https://cloudflare.com' : '';
+%>
+<!DOCTYPE html>
+<!--[if lt IE 7]> <html class="no-js ie6 oldie" lang="en-US"> <![endif]-->
+<!--[if IE 7]>    <html class="no-js ie7 oldie" lang="en-US"> <![endif]-->
+<!--[if IE 8]>    <html class="no-js ie8 oldie" lang="en-US"> <![endif]-->
+<!--[if gt IE 8]><!--> <html class="no-js" lang="en-US"> <!--<![endif]-->
+<head>
+<%
+let error_code = params.error_code || 500;
+let title = params.title || 'Internal server error';
+let html_title_output = params.html_title || (error_code + ': ' + title);
+%>
+<title><%= html_title_output %></title>
+<meta charset="UTF-8" />
+<meta http-equiv="Content-Type" content="text/html; charset=UTF-8" />
+<meta http-equiv="X-UA-Compatible" content="IE=Edge" />
+<meta name="robots" content="noindex, nofollow" />
+<meta name="viewport" content="width=device-width,initial-scale=1" />
+<link rel="stylesheet" id="cf_styles-css" href="<%= resources_cdn %>/cdn-cgi/styles/main.css" />
+</head>
+<body>
+<div id="cf-wrapper">
+        <div id="cf-error-details" class="p-0">
+        <header class="mx-auto pt-10 lg:pt-6 lg:px-8 w-240 lg:w-full mb-8">
+            <h1 class="inline-block sm:block sm:mb-2 font-light text-60 lg:text-4xl text-black-dark leading-tight mr-2">
+                <span class="inline-block"><%= title %></span>
+                <span class="code-label">Error code <%= error_code %></span>
+            </h1>
+            <% let more_info = params.more_information || {}; %>
+            <% if (!more_info.hidden) { %>
+            <div>
+                Visit <a href="<%= more_info.link || 'https://www.cloudflare.com/' %>" target="_blank" rel="noopener noreferrer"><%= more_info.text || 'cloudflare.com' %></a> for more information.
+            </div>
+            <% } %>
+            <div class="<%= more_info.hidden ? '' : 'mt-3' %>"><%= params.time %></div>
+        </header>
+        <div class="my-8 bg-gradient-gray">
+          <div class="w-240 lg:w-full mx-auto">
+                <div class="clearfix md:px-8">
+                <% for (let item_id of ['browser', 'cloudflare', 'host']) { %>
+                    <%
+                    let icon, default_location, default_name, text_color, status_text;
+
+                    if (item_id === 'browser') {
+                        icon = 'browser';
+                        default_location = 'You';
+                        default_name = 'Browser';
+                    } else if (item_id === 'cloudflare') {
+                        icon = 'cloud';
+                        default_location = 'San Francisco';
+                        default_name = 'Cloudflare';
+                    } else {
+                        icon = 'server';
+                        default_location = 'example.com';
+                        default_name = 'Host';
+                    }
+
+                    let item = params[item_id + '_status'] || {};
+                    let status = item.status || 'ok';
+
+                    if (item.status_text_color) {
+                        text_color = item.status_text_color;
+                    } else if (status === 'ok') {
+                        text_color = '#9bca3e'; // text-green-success
+                    } else if (status === 'error') {
+                        text_color = '#bd2426'; // text-red-error
+                    }
+
+                    status_text = item.status_text || (status === 'ok' ? 'Working' : 'Not Working');
+                    %>
+                    <div id="cf-<%= item_id %>-status" class="<% if (params.error_source === item_id) { %>cf-error-source<% } %> relative w-1/3 md:w-full py-15 md:p-0 md:py-8 md:text-left md:border-solid md:border-0 md:border-b md:border-gray-400 overflow-hidden float-left md:float-none text-center">
+                        <div class="relative mb-10 md:m-0">
+                            <span class="cf-icon-<%= icon %> block md:hidden h-20 bg-center bg-no-repeat"></span>
+                            <span class="cf-icon-<%= status %> w-12 h-12 absolute left-1/2 md:left-auto md:right-0 md:top-0 -ml-6 -bottom-4"></span>
+                        </div>
+                        <span class="md:block w-full truncate"><%= item.location || default_location %></span>
+                        <h3 class="md:inline-block mt-3 md:mt-0 text-2xl text-gray-600 font-light leading-1.3"><%= item.name || default_name %></h3>
+                        <span class="leading-1.3 text-2xl" style="color: <%= text_color %>"><%= status_text %></span>
+                    </div>
+                <% } %>
+                </div>
+            </div>
+        </div>
+
+        <div class="w-240 lg:w-full mx-auto mb-8 lg:px-8">
+            <div class="clearfix">
+                <div class="w-1/2 md:w-full float-left pr-6 md:pb-10 md:pr-0 leading-relaxed">
+                    <h2 class="text-3xl font-normal leading-1.3 mb-4">What happened?</h2>
+                    <%= (params.what_happened || 'There is an internal server error on Cloudflare\'s network.') %>
+                </div>
+                <div class="w-1/2 md:w-full float-left leading-relaxed">
+                    <h2 class="text-3xl font-normal leading-1.3 mb-4">What can I do?</h2>
+                    <%= (params.what_can_i_do || 'Please try again in a few minutes.') %>
+                </div>
+            </div>
+        </div>
+
+        <div class="cf-error-footer cf-wrapper w-240 lg:w-full py-10 sm:py-4 sm:px-8 mx-auto text-center sm:text-left border-solid border-0 border-t border-gray-300">
+            <p class="text-13">
+                <span class="cf-footer-item sm:block sm:mb-1">Cloudflare Ray ID: <strong class="font-semibold"><%= params.ray_id %></strong></span>
+                <span class="cf-footer-separator sm:hidden">&bull;</span>
+                <span id="cf-footer-item-ip" class="cf-footer-item hidden sm:block sm:mb-1">
+                    Your IP:
+                    <button type="button" id="cf-footer-ip-reveal" class="cf-footer-ip-reveal-btn">Click to reveal</button>
+                    <span class="hidden" id="cf-footer-ip"><%= params.client_ip || '1.1.1.1' %></span>
+                    <span class="cf-footer-separator sm:hidden">&bull;</span>
+                </span>
+                <% let perf_sec_by = params.perf_sec_by || {}; %>
+                <span class="cf-footer-item sm:block sm:mb-1"><span>Performance &amp; security by</span> <a rel="noopener noreferrer" href="<%= perf_sec_by.link || 'https://www.cloudflare.com/' %>" id="brand_link" target="_blank"><%= perf_sec_by.text || 'Cloudflare' %></a></span>
+            </p>
+        </div><!-- /.error-footer -->
+    </div>
+</div>
+<script>(function(){function d(){var b=a.getElementById("cf-footer-item-ip"),c=a.getElementById("cf-footer-ip-reveal");b&&"classList"in b&&(b.classList.remove("hidden"),c.addEventListener("click",function(){c.classList.add("hidden");a.getElementById("cf-footer-ip").classList.remove("hidden")}))}var a=document;document.addEventListener&&a.addEventListener("DOMContentLoaded",d)})();</script>
+</body>
+</html>

editor/server/__init__.py

@@ -0,0 +1,106 @@
+# SPDX-License-Identifier: MIT
+
+import os
+import secrets
+import string
+import sys
+
+from flask import Flask, request
+from flask_limiter import Limiter
+from flask_limiter.util import get_remote_address
+from flask_sqlalchemy import SQLAlchemy
+from sqlalchemy import event
+from sqlalchemy.orm import DeclarativeBase
+
+root_dir = os.path.join(os.path.dirname(os.path.abspath(__file__)), '../../')
+sys.path.append(root_dir)
+from cloudflare_error_page import render as render_cf_error_page
+
+class Base(DeclarativeBase):
+    pass
+
+db: SQLAlchemy = SQLAlchemy(model_class=Base, session_options={
+    # 'autobegin': False,
+    # 'expire_on_commit': False,
+})
+
+limiter: Limiter = Limiter(
+    key_func=get_remote_address,  # Uses client's IP address by default
+    default_limits=["200 per day", "50 per hour"] # Global default limits
+)
+
+def generate_secret(length=32) -> str:
+    characters = string.ascii_letters + string.digits  # A-Z, a-z, 0-9
+    return ''.join(secrets.choice(characters) for _ in range(length))
+
+
+def create_app(test_config=None) -> Flask:
+    instance_path = os.getenv('INSTANCE_PATH', None)
+    if instance_path is not None:
+        os.makedirs(instance_path, exist_ok=True)
+    app = Flask(__name__,
+        instance_path=instance_path,
+        instance_relative_config=True
+    )
+    app.json.ensure_ascii = False
+    app.json.mimetype = "application/json; charset=utf-8"
+    secret_key = os.getenv('SECRET_KEY', '')
+    if secret_key:
+        app.secret_key = secret_key
+    else:
+        print('Using generated secret')
+        app.secret_key = generate_secret()
+    app.config["SQLALCHEMY_DATABASE_URI"] = os.getenv('DATABASE_URI', 'sqlite:///example.db')
+    url_prefix = os.getenv('URL_PREFIX', '')
+
+
+    from . import models
+    from . import examples
+    from . import editor
+    from . import shared
+
+    if app.config["SQLALCHEMY_DATABASE_URI"].startswith('sqlite'):
+        app.config["SQLALCHEMY_ENGINE_OPTIONS"] = {
+            'isolation_level': 'SERIALIZABLE',
+            # "execution_options": {"autobegin": False}
+        }
+    db.init_app(app)
+    limiter.init_app(app)
+    
+    
+    with app.app_context():
+        db.create_all()
+        # if db.engine.dialect.name == 'sqlite':
+        #     @event.listens_for(db.engine, "connect")
+        #     def enable_foreign_keys(dbapi_connection, connection_record):
+        #         cursor = dbapi_connection.cursor()
+        #         cursor.execute("PRAGMA foreign_keys=ON;")
+        #         cursor.close()
+
+    @app.route('/health')
+    def health():
+        return '', 204
+
+    app.register_blueprint(editor.bp, url_prefix=f'{url_prefix}/editor')
+    app.register_blueprint(examples.bp, url_prefix=f'{url_prefix}/examples')
+    app.register_blueprint(shared.bp, url_prefix=f'{url_prefix}/s')
+
+    return app
+
+
+def get_common_cf_template_params():
+    # Get real Ray ID from Cloudflare header
+    ray_id = request.headers.get('Cf-Ray')
+    if ray_id:
+        ray_id = ray_id[:16]
+    # Get real client ip from Cloudflare header or request.remote_addr
+    client_ip = request.headers.get('X-Forwarded-For')
+    if not client_ip:
+        client_ip = request.remote_addr
+    return {
+        'ray_id': ray_id,
+        'client_ip': client_ip,
+    }
+
+
+__all__ = ['create_app', 'db', 'get_common_cf_template_params', 'render_cf_error_page']

editor/server/editor.py

@@ -0,0 +1,21 @@
+# SPDX-License-Identifier: MIT
+
+import os
+
+from flask import (
+    Blueprint,
+    send_from_directory,
+)
+
+from . import get_common_cf_template_params, render_cf_error_page
+
+root_dir = os.path.join(os.path.dirname(os.path.abspath(__file__)), '../../')
+res_folder = os.path.join(root_dir, 'editor/resources')
+
+bp = Blueprint('editor', __name__, url_prefix='/')
+
+
+@bp.route('/', defaults={'path': 'index.html'})
+@bp.route('/<path:path>')
+def index(path: str):
+    return send_from_directory(res_folder, path)

editor/server/examples.py

@@ -0,0 +1,58 @@
+# SPDX-License-Identifier: MIT
+
+import os
+import re
+
+from flask import (
+    Blueprint,
+    json,
+    abort,
+    redirect,
+)
+
+from . import get_common_cf_template_params, render_cf_error_page
+
+root_dir = os.path.join(os.path.dirname(os.path.abspath(__file__)), '../../')
+examples_dir = os.path.join(root_dir, 'examples')
+
+bp = Blueprint('examples', __name__, url_prefix='/')
+
+
+param_cache: dict[str, dict] = {}
+
+def get_page_params(name: str) -> dict:
+    name = re.sub(r'[^\w]', '', name)
+    params = param_cache.get(name)
+    if params is not None:
+        return params
+    try:
+        with open(os.path.join(examples_dir, f'{name}.json')) as f:
+            params = json.load(f)
+        param_cache[name] = params
+        return params
+    except Exception as _:
+        return None
+
+
+@bp.route('/', defaults={'name': 'default'})
+@bp.route('/<path:name>')
+def index(name: str):
+    name = os.path.basename(name)  # keep only the base name
+    lower_name = name.lower()
+    print(lower_name, name)
+    if name != lower_name:
+        return redirect(lower_name)
+    else:
+        name = lower_name
+
+    params = get_page_params(name)
+    if params is None:
+        abort(404)
+
+    params = {
+        **params,
+        **get_common_cf_template_params(),
+    }
+
+    # Render the error page
+    return render_cf_error_page(params, use_cdn=True), 500

editor/server/models.py

@@ -0,0 +1,19 @@
+# SPDX-License-Identifier: MIT
+
+from sqlalchemy import (
+    Column,
+    DateTime,
+    Integer,
+    JSON,
+    String,
+    func,
+)
+
+from . import db
+
+
+class Item(db.Model):
+    id = Column(Integer, primary_key=True, autoincrement=True, nullable=False)
+    name = Column(String(255), unique=True, nullable=False, index=True)
+    params = Column(JSON, nullable=False)
+    time_created = Column(DateTime(timezone=True), server_default=func.now())

editor/server/shared.py

@@ -0,0 +1,69 @@
+# SPDX-License-Identifier: MIT
+
+import random
+import string
+
+from flask import (
+    Blueprint,
+    request,
+    abort,
+    jsonify,
+    url_for,
+)
+
+from . import get_common_cf_template_params, render_cf_error_page
+from . import db
+from . import limiter
+from . import models
+
+# root_dir = os.path.join(os.path.dirname(os.path.abspath(__file__)), '../../')
+# examples_dir = os.path.join(root_dir, 'examples')
+
+bp = Blueprint('shared', __name__, url_prefix='/')
+
+
+rand_charset = string.ascii_letters + string.digits 
+
+def get_rand_name(digits=8):
+    return ''.join(random.choice(rand_charset) for _ in range(digits))
+
+
+@bp.post('/create')
+@limiter.limit("20 per minute")
+@limiter.limit("500 per hour")
+def create():
+    if len(request.data) > 4096:
+        abort(413)
+    params = request.json['parameters']  # throws KeyError
+    # TODO: strip unused params
+    try:
+        item = models.Item()
+        item.name = get_rand_name()
+        item.params = params
+        db.session.add(item)
+        db.session.commit()
+    except:
+        db.session.rollback()
+        return jsonify({
+            'status': 'failed',
+        })
+    return jsonify({
+        'status': 'ok',
+        'name': item.name,
+        'url': request.host_url[:-1] + url_for('shared.get', name=item.name),
+        # TODO: better way to handle this
+    })
+
+
+@bp.get('/<name>')
+def get(name: str):
+    item = db.session.query(models.Item).filter_by(name=name).first()
+    if not item:
+        return abort(404)
+    params = item.params
+    params = {
+        **params,
+        **get_common_cf_template_params(),
+    }
+    # TODO: cache
+    return render_cf_error_page(params=params, allow_html=False, use_cdn=True, show_creator=True), 200