Reload functions

README.md

@@ -92,3 +92,46 @@ val json = JsonSchema[Profile].schema
 Nested case classes are inlined (no `$ref`) and work to arbitrary depth.
 
 > **Limitation:** Mutually recursive case classes (e.g. `A` contains `B`, `B` contains `A`) will cause a compile-time stack overflow. Workaround: provide an explicit `given JsonSchema[B]` before deriving `A`.
+
+## Excel
+
+An optional module (`excel`) exposes Scala functions as Excel custom functions via an HTTP server.
+
+```
+┌─────────────────────────────────────────────────────────────────────────────┐
+│  Excel                                                                      │
+│                                                                             │
+│  ┌──────────────────────┐            ┌──────────────────────────────────┐   │
+│  │   Functions runtime  │            │           Task pane              │   │
+│  │   (functions.html)   │            │         (taskpane.html)          │   │
+│  │                      │            │                                  │   │
+│  │  on startup          │            │  on load / "Reload Functions"    │   │
+│  │  ┌────────────────┐  │            │  ┌────────────────────────────┐  │   │
+│  │  │loadAndRegister │──┼────────────┼─▶│  GET /functions.json       │  │   │
+│  │  └────────────────┘  │            │  └────────────────────────────┘  │   │
+│  │                      │            │       │ re-render list           │   │
+│  │  poll every 2 s      │            │       ▼                          │   │
+│  │  ┌────────────────┐  │  signal    │  OfficeRuntime.storage           │   │
+│  │  │OfficeRuntime   │◀─┼────────────┼─  .setItem("cf-reload-signal")   │   │
+│  │  │.storage.getItem│  │            │                                  │   │
+│  │  └───────┬────────┘  │            └──────────────────────────────────┘   │
+│  │          │ detected  │                                                   │
+│  │          ▼           │                                                   │
+│  │  ┌────────────────┐  │                                                   │
+│  │  │loadAndRegister │  │  (only new IDs — tracked in registeredIds Set)    │
+│  │  │  (additive)    │  │                                                   │
+│  │  └───────┬────────┘  │                                                   │
+│  │          │           │                                                   │
+│  └──────────┼───────────┘                                                   │
+└─────────────┼───────────────────────────────────────────────────────────────┘
+              │ POST /invoke  {functionId, params}
+              ▼
+     ┌─────────────────┐
+     │   Scala server  │
+     │  (http4s/ember) │
+     └─────────────────┘
+```
+
+- **`/functions.json`** — served at startup from the in-memory function list; always reflects the running server's functions.
+- **`/functions.js`** — fetches `/functions.json` at runtime and calls `CustomFunctions.associate()` dynamically; polls `OfficeRuntime.storage` every 2 s for a reload signal.
+- **Reload without add-in restart** — clicking "Reload Functions" signals the runtime to re-register new functions and refreshes the taskpane list. Formula-bar autocomplete for brand-new functions still requires a full add-in reload (Excel limitation).

excel-example/manifest.xml

@@ -30,8 +30,8 @@ Sideloading instructions:
   <DisplayName DefaultValue="ExcelMain Tst"/>
   <Description DefaultValue="Custom functions served by local ExcelMain server"/>
 
-  <IconUrl DefaultValue="http://localhost:7777/icon-32.png"/>
-  <HighResolutionIconUrl DefaultValue="http://localhost:7777/icon-80.png"/>
+  <IconUrl DefaultValue="http://localhost:7777/icon.svg"/>
+  <HighResolutionIconUrl DefaultValue="http://localhost:7777/icon.svg"/>
 
   <Hosts>
     <Host Name="Workbook"/>
@@ -111,9 +111,9 @@ Sideloading instructions:
 
     <Resources>
       <bt:Images>
-        <bt:Image id="Icon16" DefaultValue="http://localhost:7777/icon-16.png"/>
-        <bt:Image id="Icon32" DefaultValue="http://localhost:7777/icon-32.png"/>
-        <bt:Image id="Icon80" DefaultValue="http://localhost:7777/icon-80.png"/>
+        <bt:Image id="Icon16" DefaultValue="http://localhost:7777/icon.svg"/>
+        <bt:Image id="Icon32" DefaultValue="http://localhost:7777/icon.svg"/>
+        <bt:Image id="Icon80" DefaultValue="http://localhost:7777/icon.svg"/>
       </bt:Images>
       <bt:Urls>
         <bt:Url id="HtmlUrl"      DefaultValue="http://localhost:7777/functions.html"/>

excel/src/main/resources/functions-core.js

@@ -0,0 +1,25 @@
+let registeredIds = new Set();
+
+async function loadAndRegister() {
+  const data = await fetch("/functions.json").then(r => r.json());
+  for (const fn of (data.functions || [])) {
+    if (registeredIds.has(fn.id)) continue;
+    registeredIds.add(fn.id);
+    CustomFunctions.associate(fn.id, async function(...args) {
+      const params = {};
+      fn.parameters.forEach((p, i) => { params[p.name] = args[i]; });
+      const resp = await axios.post(CENTRAL_URL, { functionId: fn.id, params });
+      return resp.data;
+    });
+  }
+}
+
+loadAndRegister();
+
+setInterval(async () => {
+  const sig = await OfficeRuntime.storage.getItem("cf-reload-signal");
+  if (sig) {
+    await OfficeRuntime.storage.removeItem("cf-reload-signal");
+    await loadAndRegister();
+  }
+}, 2000);

excel/src/main/resources/taskpane.css

@@ -0,0 +1,84 @@
+* { box-sizing: border-box; }
+
+body {
+  margin: 0;
+  font-family: 'Segoe UI', Tahoma, sans-serif;
+  font-size: 13px;
+  color: #323130;
+  background: #fff;
+}
+
+#header {
+  background: #217346;
+  color: #fff;
+  padding: 12px 14px;
+  font-size: 15px;
+  font-weight: 600;
+}
+
+#search-box {
+  padding: 8px 10px;
+  border-bottom: 1px solid #edebe9;
+}
+
+#search-box input {
+  width: 100%;
+  padding: 5px 8px;
+  border: 1px solid #c8c6c4;
+  border-radius: 2px;
+  font-size: 13px;
+  outline: none;
+}
+
+#search-box input:focus { border-color: #217346; }
+
+#count {
+  padding: 4px 14px;
+  font-size: 11px;
+  color: #a19f9d;
+  background: #faf9f8;
+  border-bottom: 1px solid #edebe9;
+}
+
+.fn-card {
+  padding: 10px 14px;
+  border-bottom: 1px solid #edebe9;
+}
+
+.fn-card:hover { background: #f3f2f1; }
+
+.fn-sig {
+  font-family: 'Cascadia Code', Consolas, monospace;
+  color: #217346;
+  font-weight: 600;
+  font-size: 12px;
+}
+
+.fn-desc { color: #605e5c; margin: 3px 0 5px; font-size: 12px; }
+
+.params { list-style: none; padding: 0; margin: 0; }
+
+.params li { font-size: 11px; color: #605e5c; padding: 1px 0; }
+
+.pname { font-family: monospace; font-weight: 600; color: #323130; }
+
+.popt { color: #a19f9d; font-style: italic; }
+
+#empty { padding: 20px; text-align: center; color: #a19f9d; display: none; }
+
+#reload-btn {
+  display: block;
+  width: calc(100% - 20px);
+  margin: 8px 10px;
+  padding: 6px 12px;
+  background: #217346;
+  color: #fff;
+  border: none;
+  border-radius: 2px;
+  font-size: 13px;
+  cursor: pointer;
+}
+
+#reload-btn:hover { background: #185c37; }
+
+#reload-btn:disabled { background: #a19f9d; cursor: default; }

excel/src/main/resources/taskpane.js

@@ -0,0 +1,59 @@
+let fns = [];
+
+function sig(f) {
+  const ps = f.parameters.map(p => p.optional ? "[" + p.name + "]" : p.name).join(", ");
+  return "=" + NS_PREFIX + f.name + "(" + ps + ")";
+}
+
+function card(f) {
+  const div = document.createElement("div");
+  div.className = "fn-card";
+  const ps = f.parameters.map(p => {
+    const opt = p.optional ? ' <span class="popt">(optional)</span>' : "";
+    const desc = p.description ? " — " + p.description : "";
+    return '<li><span class="pname">' + p.name + "</span>" + opt + desc + "</li>";
+  }).join("");
+  div.innerHTML =
+    '<div class="fn-sig">' + sig(f) + "</div>" +
+    '<div class="fn-desc">' + f.description + "</div>" +
+    (ps ? '<ul class="params">' + ps + "</ul>" : "");
+  return div;
+}
+
+function render(list) {
+  const el = document.getElementById("list");
+  el.innerHTML = "";
+  list.forEach(f => el.appendChild(card(f)));
+  document.getElementById("empty").style.display = list.length ? "none" : "block";
+  document.getElementById("count").textContent =
+    list.length + " function" + (list.length === 1 ? "" : "s");
+}
+
+function doFilter() {
+  const q = document.getElementById("q").value.toLowerCase();
+  render(q
+    ? fns.filter(f => f.name.toLowerCase().includes(q) || f.description.toLowerCase().includes(q))
+    : fns);
+}
+
+fetch("/functions.json").then(r => r.json()).then(data => {
+  fns = data.functions || [];
+  render(fns);
+});
+
+async function reload() {
+  const btn = document.getElementById("reload-btn");
+  btn.disabled = true;
+  btn.textContent = "Reloading…";
+  try {
+    await OfficeRuntime.storage.setItem("cf-reload-signal", "1");
+    const data = await fetch("/functions.json").then(r => r.json());
+    fns = data.functions || [];
+    doFilter();
+    btn.textContent = "Reload Functions";
+  } catch(e) {
+    btn.textContent = "Error — retry";
+  } finally {
+    btn.disabled = false;
+  }
+}

excel/src/main/scala/jsonschema/excel/Excel.scala

@@ -15,12 +15,16 @@ import io.circe.Json
  */
 class Excel(functions: List[ExcelFunction.Def], centralUrl: String, namespace: String = ""):
 
-  def functionsJs(): String = ExcelJsGenerator.generate(functions, centralUrl, true)
+  def functionsJs(): String = ExcelJsGenerator.generate(centralUrl, true)
 
   def functionsJson(): Json = ExcelFunctionsManifest(functions).toJson
 
   def functionsHtml(): String = ExcelHtml.functionsHtml
 
   def taskpaneHtml(): String = ExcelHtml.taskpaneHtml(namespace)
 
-  def iconPng(size: Int): Array[Byte] = ExcelIcon.png(size)
+  def taskpaneCss(): String = ExcelHtml.taskpaneCss
+
+  def taskpaneJs(): String = ExcelHtml.taskpaneJs
+
+  val iconSvg: String = ExcelHtml.iconSvg