Improve metadata handling

src/lib/page.ts

@@ -1,15 +1,16 @@
 import { open } from "fs/promises";
+import { parse, stringify } from "yaml";
 
-export const createFileIfNotExists = async (fileName: string) => {
+export const createPageIfNotExists = async (fileName: string) => {
 	const filePath = `pages/${fileName}.md`;
 	try {
 		const date = new Date().toISOString();
 		const file = await open(filePath, "wx+");
 		await file.writeFile(
 			`---
-title: ${fileName}
 date_created: ${date}
 date_modified: ${date}
+date_visited: ${date}
 ---`,
 			{ encoding: "utf-8" },
 		);
@@ -26,10 +27,32 @@ date_modified: ${date}
 	}
 };
 
-export const getFileInfo = async (fileName: string) => {
-	createFileIfNotExists(fileName);
+export const getPageInfo = async (fileName: string) => {
+	createPageIfNotExists(fileName);
 	const file = await open(`pages/${fileName}.md`, "r");
-	const content = await file.readFile({ encoding: "utf-8" });
+	const body = await file.readFile({ encoding: "utf-8" });
+	const [, preamble, content] = body.split("---").map((s) => s.trim());
+	const metadata = parse(preamble);
+	await file.close();
+	return { content, metadata };
+};
+
+export const writePage = async (
+	fileName: string,
+	options: { content?: string; metadata?: object },
+) => {
+	const { content: oldContent, metadata: oldMetadata } = await getPageInfo(fileName);
+	const file = await open(`pages/${fileName}.md`, "w");
+	await file.writeFile(
+		[
+			"---",
+			stringify(Object.assign(oldMetadata, options.metadata)).trim(),
+			"---",
+			options.content || oldContent,
+		].join("\n"),
+		{
+			encoding: "utf-8",
+		},
+	);
 	await file.close();
-	return { content };
 };

src/routes/api/save/[page]/+server.ts

@@ -1,9 +1,8 @@
-import { writeFile } from "fs/promises";
 import type { RequestHandler } from "./$types";
+import { writePage } from "$lib/page";
 
 export const PUT: RequestHandler = async ({ request, params }) => {
-	// write fileContents from request to a file with the name fileName from request
 	const { fileContents } = await request.json();
-	await writeFile(`pages/${params.page}.md`, fileContents, "utf-8");
+	await writePage(params.page, { content: fileContents });
 	return new Response(null, { status: 204 });
 };

src/routes/page/[page]/+page.server.ts

@@ -1,8 +1,11 @@
-import { getFileInfo } from "$lib/page";
+import { getPageInfo, writePage } from "$lib/page";
 import type { PageServerLoad } from "./$types";
 
 export const load: PageServerLoad = async ({ params }) => {
-	const { content } = await getFileInfo(params.page);
+	const { content } = await getPageInfo(params.page);
+	await writePage(params.page, {
+		metadata: { date_visited: new Date().toISOString() },
+	});
 	return {
 		fileName: params.page,
 		content,