feat: add http2

lib/client.js

@@ -1289,7 +1289,11 @@ function write (client, request) {
   let header
 
   if (upgrade) {
-    header = `${method} ${path} HTTP/1.1\r\nconnection: upgrade\r\nupgrade: ${upgrade}\r\n`
+    let connectionString = "upgrade";
+    if (headers.toLowerCase().includes("http2-settings")) {
+      connectionString += ", http2-settings";
+    }
+    header = `${method} ${path} HTTP/1.1\r\nconnection: ${connectionString}\r\nupgrade: ${upgrade}\r\n`
   } else if (client[kPipelining]) {
     header = `${method} ${path} HTTP/1.1\r\nconnection: keep-alive\r\n`
   } else {

lib/http2client.js

@@ -0,0 +1,79 @@
+"use strict";
+/* eslint-disable no-unused-vars, max-len, id-length */
+
+const assert = require("assert");
+const { kUrl, kSocket, kHTTP2Opts } = require("./core/symbols");
+
+const FRAME_TYPES = [
+	"DATA", // standard request / response payloads
+	"HEADERS", // starts stream, carries request headers
+	"PRIORITY", // advises the priority of a stream
+	"RST_STREAM", // immediately terminates a stream
+	"SETTINGS", // inform other end of endpoint config
+	"PUSH_PROMISE", // pre-warns peer of wanted streams
+	"PING",
+	"GOAWAY", // graceful version of RST_STREAM
+	"WINDOW_UPDATE", // defines flow-control
+	"CONTINUATION" // continue a sequence of headers
+];
+
+function parseHttp2Settings(settings) {
+	// under RFC7540 section 3.2.1, the settings must be a base64url encoded
+	// SETTINGS frame. 16 bit identifiers, 32 bit values. */
+	let parsed = "";
+	for (let i = 0; i < Object.keys(settings).length; i += 2) {
+		parsed += `${settings[i]}${settings[i + 1]}\r\n`;
+	}
+
+	// base64url polyfill, courtesy of @panva
+	let encoded;
+	if (Buffer.isEncoding("base64url")) {
+		encoded = Buffer.from(parsed)
+			.toString("base64url")
+			.replace(/[=]+$/g, "");
+	} else {
+		encoded = Buffer.from(parsed)
+			.toString("base64")
+			.replace(/\+/g, "-")
+			.replace(/\//g, "_")
+			.replace(/[=]+$/g, "");
+	}
+	return encoded;
+}
+
+function http2Connect(client) {
+	assert(!client[kSocket]);
+	const { protocol, port, hostname, pathname } = client[kUrl];
+	if (protocol === "https:") {
+		throw new Error("Invalid protocol - httpConnect upgrades http streams");
+	}
+	// TODO: allow ALT-SVC
+	client.upgrade({
+		path: pathname,
+		protocol: "h2c",
+		headers: {
+			"HTTP2-Settings": parseHttp2Settings(client[kHTTP2Opts] || {})
+		}
+	})
+		.then((res) => {
+			console.log("hi");
+			console.log(res);
+		})
+		.catch((err) => {
+			if (err.code === "UND_ERR_SOCKET" && err.message === "bad upgrade") {
+				// do not upgrade
+			} else {
+				throw err;
+			}
+		});
+}
+
+function https2Connect(client) {
+	const { protocol, port, hostname } = client[kUrl];
+	if (protocol === "http:") {
+		throw new Error("Invalid protocol - https2Connect upgrades https streams");
+	}
+	// TODO: tls negotiation comes FIRST
+}
+
+module.exports = http2Connect;