給 Astro 開發者的 EmDash

EmDash 是專為 Astro 打造的 CMS，而不是掛上 Astro 轉接器的通用無頭 CMS。它在保留你熟悉開發體驗的同時，為網站加入資料庫支援的內容、精緻的管理介面，以及 WordPress 風格的功能（選單、小工具、分類法）。

你對 Astro 的了解仍然成立。EmDash 強化網站，而不是取代你的工作流程。

EmDash 補上的能力

EmDash 提供純檔案型 Astro 網站通常缺少的內容管理功能：

Astro Collections 與 EmDash

Astro 的 astro:content 集合以檔案為基礎，在建置階段解析。EmDash 集合由資料庫支援，在執行時解析。

兩者並用

Astro 集合與 EmDash 可以共存。開發者內容（文件、變更紀錄）用 Astro；編輯內容（文章、頁面）用 EmDash。

---
import { getCollection } from "astro:content";
import { getEmDashCollection } from "emdash";

// Developer-managed docs from files
const docs = await getCollection("docs");

// Editor-managed posts from database
const { entries: posts } = await getEmDashCollection("posts", {
  status: "published",
  limit: 5,
});
---

設定

EmDash 需要兩個設定檔。

Astro 整合

import { defineConfig } from "astro/config";
import emdash, { local } from "emdash/astro";
import { sqlite } from "emdash/db";

export default defineConfig({
	output: "server", // Required for EmDash
	integrations: [
		emdash({
			database: sqlite({ url: "file:./data.db" }),
			storage: local({
				directory: "./uploads",
				baseUrl: "/_emdash/api/media/file",
			}),
		}),
	],
});

Live Collections Loader

import { defineLiveCollection } from "astro:content";
import { emdashLoader } from "emdash/runtime";

export const collections = {
	_emdash: defineLiveCollection({
		loader: emdashLoader(),
	}),
};

這會將 EmDash 註冊為即時內容來源。_emdash 集合在內部路由到你的內容類型（posts、pages、products 等）。

查詢內容

EmDash 提供遵循 Astro live content collections 模式的查詢函式，回傳 { entries, error } 或 { entry, error }：

import { getEmDashCollection, getEmDashEntry } from "emdash";

// Get all published posts - returns { entries, error }
const { entries: posts } = await getEmDashCollection("posts", {
status: "published",
});

// Get a single post by slug - returns { entry, error, isPreview }
const { entry: post } = await getEmDashEntry("posts", "my-post");

import { getCollection, getEntry } from "astro:content";

// Get all blog entries
const posts = await getCollection("blog");

// Get a single entry by slug
const post = await getEntry("blog", "my-post");

篩選選項

getEmDashCollection 支援 Astro getCollection 所沒有的篩選：

const { entries: posts } = await getEmDashCollection("posts", {
	status: "published", // draft | published | archived
	limit: 10, // max results
	where: { category: "news" }, // taxonomy filter
});

呈現內容

EmDash 將富文字存成結構化 JSON 格式 Portable Text。以 PortableText 元件呈現：

---
import { getEmDashEntry } from "emdash";
import { PortableText } from "emdash/ui";

const { slug } = Astro.params;
const { entry: post } = await getEmDashEntry("posts", slug);

if (!post) {
return Astro.redirect("/404");
}

---

<article>
  <h1>{post.data.title}</h1>
  <PortableText value={post.data.content} />
</article>

---
import { getEntry, render } from "astro:content";

const { slug } = Astro.params;
const post = await getEntry("blog", slug);
const { Content } = await render(post);

---

<article>
  <h1>{post.data.title}</h1>
  <Content />
</article>

動態功能

EmDash 提供 Astro 內容層所沒有的 WordPress 風格 API。

導覽選單

---
import { getMenu } from "emdash";

const primaryMenu = await getMenu("primary");
---

{primaryMenu && (
  <nav>
    <ul>
      {primaryMenu.items.map(item => (
        <li>
          <a href={item.url}>{item.label}</a>
          {item.children.length > 0 && (
            <ul>
              {item.children.map(child => (
                <li><a href={child.url}>{child.label}</a></li>
              ))}
            </ul>
          )}
        </li>
      ))}
    </ul>
  </nav>
)}

小工具區域

---
import { getWidgetArea } from "emdash";
import { PortableText } from "emdash/ui";

const sidebar = await getWidgetArea("sidebar");
---

{sidebar && sidebar.widgets.length > 0 && (
  <aside>
    {sidebar.widgets.map(widget => (
      <div class="widget">
        {widget.title && <h3>{widget.title}</h3>}
        {widget.type === "content" && widget.content && (
          <PortableText value={widget.content} />
        )}
      </div>
    ))}
  </aside>
)}

網站設定

---
import { getSiteSettings, getSiteSetting } from "emdash";

const settings = await getSiteSettings();
// Or fetch individual values:
const title = await getSiteSetting("title");
---

<header>
  {settings.logo ? (
    <img src={settings.logo.url} alt={settings.title} />
  ) : (
    <span>{settings.title}</span>
  )}
  {settings.tagline && <p>{settings.tagline}</p>}
</header>

外掛

以可新增 hook、儲存空間、設定與管理 UI 的外掛擴充 EmDash：

import emdash from "emdash/astro";
import seoPlugin from "@emdash-cms/plugin-seo";

export default defineConfig({
	integrations: [
		emdash({
			// ...
			plugins: [seoPlugin({ generateSitemap: true })],
		}),
	],
});

使用 definePlugin 建立自訂外掛：

import { definePlugin } from "emdash";

export default definePlugin({
	id: "analytics",
	version: "1.0.0",
	capabilities: ["read:content"],

	hooks: {
		"content:afterSave": async (event, ctx) => {
			ctx.log.info("Content saved", { id: event.content.id });
		},
	},

	admin: {
		settingsSchema: {
			trackingId: { type: "string", label: "Tracking ID" },
		},
	},
});

伺服器端呈現

EmDash 網站以 SSR 模式運作。內容變更不必重新建置就會生效。

對含 getStaticPaths 的靜態頁面，內容在建置時取得：

---
import { getEmDashCollection, getEmDashEntry } from "emdash";

export async function getStaticPaths() {
  const { entries: posts } = await getEmDashCollection("posts", {
    status: "published",
  });

  return posts.map((post) => ({
    params: { slug: post.data.slug },
  }));
}

const { slug } = Astro.params;
const { entry: post } = await getEmDashEntry("posts", slug);
---

對動態頁面設定 prerender = false，讓每次請求載入內容：

---
export const prerender = false;

import { getEmDashEntry } from "emdash";

const { slug } = Astro.params;
const { entry: post, error } = await getEmDashEntry("posts", slug);

if (error) {
  return new Response("Server error", { status: 500 });
}

if (!post) {
  return new Response(null, { status: 404 });
}
---

下一步