Admin: write blog posts and manage images

A Posts page lists every post with Write a post: title, topic, kind,
date, summary, a cover picked from the vault or uploaded, the pages it is
about, the Markdown body with a rendered preview, and Save draft or
Publish. An Images page uploads several images into an _attachments
folder, shows which notes use each one, copies its embed line, and
deletes unused ones. The content service gains the attachment list,
upload and delete endpoints behind the editor and admin tokens.

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_012aSbo2D1qP8cMFQCykf7kx

services/content/src/vault.ts

@@ -2,7 +2,7 @@
  * The Site folder on disk. Only the content service reads or writes it.
  */
 import { createHash } from "node:crypto";
-import { existsSync, mkdirSync, readFileSync, readdirSync, renameSync, statSync, writeFileSync } from "node:fs";
+import { existsSync, mkdirSync, readFileSync, readdirSync, renameSync, statSync, unlinkSync, writeFileSync } from "node:fs";
 import { basename, dirname, join, relative, sep } from "node:path";
 
 export const hashText = (text: string) => createHash("sha256").update(text).digest("hex");
@@ -22,6 +22,42 @@ export function isNotePath(rel: string): boolean {
   return true;
 }
 
+/** Image types the admin page may add to `_attachments`. SVG stays out: it can carry script. */
+export const uploadTypes: Record<string, string> = {
+  ".png": "image/png",
+  ".jpg": "image/jpeg",
+  ".jpeg": "image/jpeg",
+  ".webp": "image/webp",
+  ".gif": "image/gif",
+  ".avif": "image/avif",
+};
+
+/** A safe attachment file name: lowercase words joined by hyphens, plus the extension. */
+export function attachmentName(original: string): string | null {
+  const m = /^(.*?)(\.[A-Za-z0-9]+)?$/.exec(basename(original.replace(/\\/g, "/")));
+  const ext = (m?.[2] ?? "").toLowerCase();
+  if (!uploadTypes[ext]) return null;
+  const stem = (m?.[1] ?? "")
+    .normalize("NFKD")
+    .replace(/[\u0300-\u036f]/g, "")
+    .toLowerCase()
+    .replace(/[^a-z0-9]+/g, "-")
+    .replace(/^-+|-+$/g, "")
+    .slice(0, 80);
+  return `${stem || "image"}${ext === ".jpeg" ? ".jpg" : ext}`;
+}
+
+/** A folder under `_attachments`: one plain name like Posts or Pages. */
+const folderOk = (f: string) => /^[A-Za-z0-9][A-Za-z0-9 _-]{0,40}$/.test(f);
+
+export interface AttachmentFile {
+  name: string;
+  /** The folder under `_attachments`, or "" for its top level. */
+  folder: string;
+  size: number;
+  modified: string;
+}
+
 export class Vault {
   constructor(readonly dir: string) {}
 
@@ -77,6 +113,56 @@ export class Vault {
     return out;
   }
 
+  /** Every file in `_attachments` with its folder, size and time. */
+  attachmentFiles(): AttachmentFile[] {
+    const root = join(this.dir, "_attachments");
+    const out: AttachmentFile[] = [];
+    const walk = (d: string) => {
+      if (!existsSync(d)) return;
+      for (const e of readdirSync(d, { withFileTypes: true })) {
+        if (e.name.startsWith(".")) continue;
+        const full = join(d, e.name);
+        if (e.isDirectory()) walk(full);
+        else if (e.isFile()) {
+          const st = statSync(full);
+          const folder = relative(root, d).split(sep).join("/");
+          out.push({ name: e.name, folder, size: st.size, modified: st.mtime.toISOString() });
+        }
+      }
+    };
+    walk(root);
+    return out.sort((a, b) => b.modified.localeCompare(a.modified) || a.name.localeCompare(b.name));
+  }
+
+  /**
+   * Add an image to `_attachments/<folder>`. Names are made safe, and a name
+   * already used anywhere in `_attachments` gets -2, -3 and so on, because
+   * Obsidian links attachments by file name alone.
+   */
+  addAttachment(folder: string, original: string, bytes: Uint8Array): string {
+    if (!folderOk(folder)) throw new Error("Use a plain folder name, like Posts");
+    const safe = attachmentName(original);
+    if (!safe) throw new Error(`Only ${Object.keys(uploadTypes).join(", ")} images can be added`);
+    const taken = new Set(this.listAttachments().map((n) => n.toLowerCase()));
+    const dot = safe.lastIndexOf(".");
+    let name = safe;
+    for (let i = 2; taken.has(name.toLowerCase()); i++) name = `${safe.slice(0, dot)}-${i}${safe.slice(dot)}`;
+    const full = join(this.dir, "_attachments", folder, name);
+    mkdirSync(dirname(full), { recursive: true });
+    const tmp = join(dirname(full), `.${name}.${process.pid}.tmp`);
+    writeFileSync(tmp, bytes);
+    renameSync(tmp, full);
+    return name;
+  }
+
+  /** Delete an attachment by file name. False when there is none. */
+  removeAttachment(name: string): boolean {
+    const file = name.includes("/") || name.includes("\\") || name.includes("..") ? null : this.attachmentPath(name);
+    if (!file) return false;
+    unlinkSync(file);
+    return true;
+  }
+
   /** Absolute path of an attachment by file name, for serving images. */
   attachmentPath(name: string): string | null {
     const walk = (d: string): string | null => {