W5 done

w5/utils.js

@@ -0,0 +1,89 @@
+"use strict";
+
+import { readFileSync } from "fs";
+import { IncomingMessage, ServerResponse } from "http";
+import { parse as urlParse } from "querystring";
+
+/**
+ * 
+ * @param {ServerResponse} res 
+ * @param {String} filename 
+ * @param {Array.<Array.<String, Object>>} params 
+ */
+export function renderTemplate(res, filename, params = []) {
+    let templateText = readFileSync(filename, "utf-8");
+    params.forEach(el => {
+        const [k, v] = el;
+        templateText = templateText.replace(new RegExp(`\{\{${k}\}\}`, "g"), v);
+    });
+    res.writeHead(200, { "Content-Type": "text/html" });
+    res.write(templateText);
+    res.end();
+}
+
+/**
+ * 
+ * @param {IncomingMessage} req
+ */
+export function getCookies(req) {
+    const list = {};
+    const cookieHeader = req.headers?.cookie;
+    if (!cookieHeader) return list;
+
+    cookieHeader.split(";").forEach(function (cookie) {
+        let [name, ...rest] = cookie.split("=");
+        name = name?.trim();
+        if (!name) return;
+        const value = rest.join("=").trim();
+        if (!value) return;
+        list[name] = decodeURIComponent(value);
+    });
+
+    return list;
+}
+
+/**
+ * 
+ * @param {ServerResponse} res 
+ * @param {Object} cookies 
+ */
+export function setCookies(res, cookies = {}) {
+    res.setHeader(
+        "Set-Cookie",
+        Array.from(Object.keys(cookies))
+            .map(e => `${encodeURIComponent(e)}=${encodeURIComponent(cookies[e])}`)
+            .join(";")
+    );
+}
+
+/**
+ * 
+ * @param {ServerResponse} res 
+ * @param {String} path 
+ */
+export function redirect(res, path) {
+    res.statusCode = 307;
+    res.setHeader("Location", path);
+    res.end();
+}
+
+export function consumePostForm(req) {
+    return new Promise((resolve, reject) => {
+        let body = "";
+        req.on("data", function (data) {
+            try {
+                body += data;
+                if (body.length > 1e6) {
+                    req.destroy();
+                }
+            } catch (e) { reject(e); }
+        });
+        req.on("end", function () {
+            try {
+                const post = urlParse(body);
+                resolve(post);
+            } catch (e) { reject(e); }
+        });
+    });
+}
+