Add, reorder or remove a section on many pages

PUT /cdna-api/pages/page/1885?properties={id,activeRevision{id}}
Content-Type: application/json

{
  "patchRevision": {
    "originRevision": 3447,
    "activeRevision": true,
    "appendAreaCollectionElement(pageSections)": {
      "layout": 58,
      "name": "Sandbox figure",
      "areas": {"image": 1185, "alt": "A blue and green gradient", "caption": "Uploaded through the API"}
    }
  }
}

# 200 {"result":"success","data":{"id":1885,"activeRevision":{"id":3482}},"message":"The Page has been saved successfully."}

// rewrite-sections.js (Node 18 or later); coredna() is your client module, as in
// https://hub.coredna.com/books/apis/client/client-layer
import { coredna } from './coredna.js';

function toWrite(area) {                     // one area of areasContent -> the value a write takes
  if (!area || typeof area !== 'object') return area ?? null;
  switch (area.category) {
    case 'collection': return (area.collection ?? []).map(componentToWrite);
    case 'component':  return area.component ? componentToWrite(area.component) : null;
    case 'image':      return area.imageId ?? null;
    case 'file':       return area.fileId ?? null;
    case 'record':     return area.record?.id ?? null;
    case 'records':    return (area.records ?? []).map((r) => r.id);
    default:
      if ('active' in area) return area.active;   // a switch
      return area.text ?? null;                    // text, rich text, select, date; a multiselect's JSON string
  }
}

function componentToWrite(c) {
  if (c.componentGlobal) return { global: true, id: c.componentId };   // keep the reference, not a copy
  const areas = {};
  for (const [name, area] of Object.entries(c)) {
    if (name.startsWith('component')) continue;
    const value = toWrite(area);
    if (value !== null) areas[name] = value;
  }
  return { name: c.componentName, layout: c.componentLayout, areas };
}

// change(list) returns the new list: reordered, filtered, or both
export async function rewriteSections(pageId, change) {
  const { data } = await coredna('GET', 'pages/page/' + pageId, {
    query: { properties: '{id,activeRevision{id,areasContent}}' },
  });
  const live = data.activeRevision;
  const before = toWrite(live.areasContent.pageSections) ?? [];
  const after = change(before);
  const result = await coredna('PUT', 'pages/page/' + pageId, {
    query: { properties: '{id,activeRevision{id}}' },
    body: { patchRevision: { originRevision: live.id, activeRevision: true, 'areaContent(pageSections)': after } },
  });
  console.log(pageId, live.id, '->', result.data.activeRevision.id, before.length, '->', after.length);
}

// remove every section built on a retired component layout:
// await rewriteSections(1885, (list) => list.filter((s) => s.layout !== 41));
// move the last section to the top:
// await rewriteSections(1885, (list) => [list.at(-1), ...list.slice(0, -1)]);