I just learned that URL unfurling is a thing, and now this chat client supports it (poorly).

git-svn-id: https://www.unprompted.com/svn/projects/tildefriends/trunk@3335 ed5197a5-7fde-0310-b194-c3ffbd925b24

core/client.js

@@ -280,8 +280,12 @@ function printStructured(container, data) {
 			node.setAttribute("target", data.target || "_blank");
 		} else if (data.iframe) {
 			node = document.createElement("iframe");
-			node.setAttribute("srcdoc", data.iframe);
-			node.setAttribute("sandbox", "allow-forms allow-scripts allow-top-navigation");
+			if (data.src) {
+				node.setAttribute("src", data.src);
+			} else {
+				node.setAttribute("srcdoc", data.iframe);
+			}
+			node.setAttribute("sandbox", "allow-forms allow-scripts allow-top-navigation allow-same-origin");
 			node.setAttribute("width", data.width || 320);
 			node.setAttribute("height", data.height || 240);
 			if (data.name) {
@@ -519,7 +523,13 @@ function blur() {
 }
 
 function onMessage(event) {
-	send({event: "onWindowMessage", message: event.data});
+	if (event.data && event.data.event == "resizeMe" && event.data.width && event.data.height) {
+		var iframe = document.getElementById("iframe_" + event.data.name);
+		iframe.setAttribute("width", event.data.width);
+		iframe.setAttribute("height", event.data.height);
+	} else {
+		send({event: "onWindowMessage", message: event.data});
+	}
 }
 
 function submitButton() {

packages/cory/chat/chat.js

@@ -250,8 +250,9 @@ function updateConversation() {
 				terminal.clear();
 				printToConversation(gCurrentConversation, ["[", gCurrentConversation.name, "]"]);
 				if (history) {
+					let previous = Promise.resolve();
 					for (let message of history) {
-						printToConversation(gCurrentConversation, message);
+						previous = previous.then(x => printToConversation(gCurrentConversation, message));
 					}
 				}
 				updateUsers();
@@ -326,10 +327,10 @@ function getConversation(session, conversationName) {
 	return result;
 }
 
-function printToConversation(conversation, message, notify) {
+async function printToConversation(conversation, message, notify) {
 	if (conversation == gCurrentConversation) {
 		if (message.action == "message") {
-			printMessage(message.message);
+			await printMessage(message.message);
 		} else if (message.action == "presence") {
 			if (message.presence == "unavailable") {
 				terminal.print(new Date().toString(), ": ", message.user, " has left the room.");
@@ -405,7 +406,7 @@ function niceTime(lastTime, thisTime) {
 	return result.join(" ");
 }
 
-function formatMessage(message) {
+async function formatMessage(message) {
 	var result;
 	if (typeof message == "string") {
 		for (let i = 0; i < message.length; i++) {
@@ -417,9 +418,17 @@ function formatMessage(message) {
 		var regex = /(\w+:\/*\S+?)(?=(?:[\.!?])?(?:$|\s))/gi;
 		var match;
 		var lastIndex = 0;
+		let libunfurl;
 		while ((match = regex.exec(message)) !== null) {
+			if (!libunfurl) {
+				libunfurl = await core.getService("libunfurl", "libunfurl");
+			}
 			result.push({class: "base1", value: message.substring(lastIndex, match.index)});
-			result.push({href: match[0]});
+			if (!libunfurl) {
+				result.push({href: match[0]});
+			} else {
+				result.push(await libunfurl.postMessage(match[0]));
+			}
 			lastIndex = regex.lastIndex;
 		}
 		result.push({class: "base1", value: message.substring(lastIndex)});
@@ -430,7 +439,7 @@ function formatMessage(message) {
 }
 
 var lastTimestamp = null;
-function printMessage(message) {
+async function printMessage(message) {
 	var now = message.timestamp || new Date().toString();
 	var from = message.from || "unknown";
 
@@ -441,7 +450,7 @@ function printMessage(message) {
 		{class: "base3", value: from},
 		{class: "base00", value: ">"},
 		" ",
-		formatMessage(message.message));
+		await formatMessage(message.message));
 	lastTimestamp = now;
 }
 

packages/cory/libunfurl/libunfurl.js

@@ -0,0 +1,67 @@
+"use strict";
+
+//! {"category": "libraries", "require": ["libhttp", "libxml"], "permissions": ["network"]}
+
+let libxml = require("libxml");
+let libhttp = require("libhttp");
+
+let gEmbedIndex = 0;
+
+async function unfurl(url) {
+	let result = {href: url};
+	let response = await libhttp.get(url);
+	let parsed = libxml.StreamParser().parse(response.body);
+	let oEmbedUrl;
+	for (let node of parsed) {
+		if (node.type == "element" && node.value == "link" && node.attributes.type == "application/json+oembed") {
+			oEmbedUrl = node.attributes.href;
+			break;
+		}
+	}
+
+	if (oEmbedUrl) {
+		response = await libhttp.get(oEmbedUrl);
+		let oEmbed = JSON.parse(response.body);
+		gEmbedIndex++;
+		result = [{href: url}, "\n", {
+			name: "oEmbed" + gEmbedIndex,
+			iframe: `
+	<span style="border: 0; padding: 0; margin: 0; overflow: hidden">
+		${oEmbed.html}
+	</span>
+	<script language="javascript">
+		let gResizeMeMessage = {
+			event: "resizeMe",
+			name: "oEmbed${gEmbedIndex}",
+			width: -1,
+			height: -1,
+		};
+		setInterval(function() {
+			if (document.body.scrollHeight != gResizeMeMessage.height
+				|| document.body.scrollWidth != gResizeMeMessage.width) {
+				gResizeMeMessage.width = document.body.scrollWidth;
+				gResizeMeMessage.height = document.body.scrollHeight;
+				parent.postMessage(gResizeMeMessage, "*");
+			}
+		}, 100);
+	</script>
+`,
+			width: oEmbed.width || 320,
+			height: oEmbed.height || 120,
+			style: "margin: 0; padding: 0; border: 0; overflow: hidden",
+		}];
+	}
+
+	return result;
+}
+
+async function test() {
+	terminal.print(await unfurl("https://twitter.com/511nyAlbany/status/777221230915096576"));
+	terminal.print(await unfurl("https://www.youtube.com/watch?v=pTA0DSfrGZ0"));
+}
+
+//test().catch(terminal.print);
+
+core.register("onMessage", function(sender, message) {
+	return unfurl(message).catch(error => [message, "(error retrieving: ", error, ")"]);
+});

packages/cory/libxml/libxml.js

@@ -251,4 +251,11 @@ exports.StanzaParser = function(depth) {
 		parse: parser.parse.bind(parser),
 		reset: parser.reset.bind(parser),
 	};
+}
+
+exports.StreamParser = function() {
+	let parser = new XmlStreamParser();
+	return {
+		parse: parser.parse.bind(parser),
+	};
 }