Add saver for Hyperdrive protocol used in Beaker 1.x (#4777)

core/modules/savers/hyperdrive.js

@@ -0,0 +1,64 @@
+/*\
+title: $:/core/modules/savers/hyperdrive.js
+type: application/javascript
+module-type: saver
+
+Saves files using the Hyperdrive Protocol (https://hypercore-protocol.org/#hyperdrive) Beaker browser beta-1.0 and later (https://beakerbrowser.com)
+Compatible with beaker >= V1.0.0
+
+\*/
+(function(){
+
+/*jslint node: true, browser: true */
+/*global $tw: false */
+"use strict";
+
+/*
+Set up the saver
+*/
+var HyperdriveSaver = function(wiki) {
+	this.wiki = wiki;
+};
+
+HyperdriveSaver.prototype.save = function(text,method,callback) {
+	var dat = beaker.hyperdrive.drive("" + window.location),
+		pathname = ("" + window.location.pathname).split("#")[0];
+	dat.stat(pathname).then(function(value) {
+		if(value.isDirectory()) {
+			pathname = pathname + "/index.html";
+		}
+		dat.writeFile(pathname,text,"utf8").then(function(value) {
+			callback(null);
+		},function(reason) {
+			callback("Hyperdrive Saver Write Error: " + reason);
+		});
+	},function(reason) {
+		callback("Hyperdrive Saver Stat Error: " + reason);
+	});
+	return true;
+};
+
+/*
+Information about this saver
+*/
+HyperdriveSaver.prototype.info = {
+	name: "beaker-1.x",
+	priority: 3000,
+	capabilities: ["save", "autosave"]
+};
+
+/*
+Static method that returns true if this saver is capable of working
+*/
+exports.canSave = function(wiki) {
+	return !!window.beaker && !!beaker.hyperdrive && location.protocol==="hyper:";
+};
+
+/*
+Create an instance of this saver
+*/
+exports.create = function(wiki) {
+	return new HyperdriveSaver(wiki);
+};
+
+})();