From 66ea26f4bd2c4a669ca0fa0158fd0f4e0e8f38b4 Mon Sep 17 00:00:00 2001
From: Pavel Djundik <github@xpaw.me>
Date: Sun, 13 Aug 2017 12:58:27 +0300
Subject: [PATCH] Resolve relative URIs in link previewer

Also adds support for image_src links
---
 src/plugins/irc-events/link.js | 14 +++++++---
 test/plugins/link.js           | 48 +++++++++++++++++++++++++++++-----
 2 files changed, 51 insertions(+), 11 deletions(-)

diff --git a/src/plugins/irc-events/link.js b/src/plugins/irc-events/link.js
index 67e2db89..49e9f14e 100644
--- a/src/plugins/irc-events/link.js
+++ b/src/plugins/irc-events/link.js
@@ -2,6 +2,7 @@
 
 const cheerio = require("cheerio");
 const request = require("request");
+const url = require("url");
 const Helper = require("../../helper");
 const findLinks = require("../../../client/js/libs/handlebars/ircmessageparser/findLinks");
 const es = require("event-stream");
@@ -62,8 +63,13 @@ function parse(msg, preview, res, client) {
 		preview.thumb =
 			$("meta[property=\"og:image\"]").attr("content")
 			|| $("meta[name=\"twitter:image:src\"]").attr("content")
+			|| $("link[rel=\"image_src\"]").attr("href")
 			|| "";
 
+		if (preview.thumb.length) {
+			preview.thumb = url.resolve(preview.link, preview.thumb);
+		}
+
 		// Make sure thumbnail is a valid url
 		if (!/^https?:\/\//.test(preview.thumb)) {
 			preview.thumb = "";
@@ -111,8 +117,8 @@ function handlePreview(client, msg, preview, res) {
 		return emitPreview(client, msg, preview);
 	}
 
-	storage.store(res.data, res.type.replace("image/", ""), (url) => {
-		preview.thumb = url;
+	storage.store(res.data, res.type.replace("image/", ""), (uri) => {
+		preview.thumb = uri;
 
 		emitPreview(client, msg, preview);
 	});
@@ -135,11 +141,11 @@ function emitPreview(client, msg, preview) {
 	});
 }
 
-function fetch(url, cb) {
+function fetch(uri, cb) {
 	let req;
 	try {
 		req = request.get({
-			url: url,
+			url: uri,
 			maxRedirects: 5,
 			timeout: 5000,
 			headers: {
diff --git a/test/plugins/link.js b/test/plugins/link.js
index 912d3de1..dfd73b0f 100644
--- a/test/plugins/link.js
+++ b/test/plugins/link.js
@@ -110,21 +110,55 @@ describe("Link plugin", function() {
 		});
 	});
 
-	it("should not use thumbnail with invalid url", function(done) {
+	it("should find image_src", function(done) {
 		const message = this.irc.createMessage({
-			text: "http://localhost:9002/invalid-thumb"
+			text: "http://localhost:9002/thumb-image-src"
 		});
 
 		link(this.irc, this.network.channels[0], message);
 
-		this.app.get("/invalid-thumb", function(req, res) {
-			res.send("<title>test invalid image</title><meta property='og:image' content='/real-test-image.png'>");
+		this.app.get("/thumb-image-src", function(req, res) {
+			res.send("<link rel='image_src' href='http://localhost:9002/real-test-image.png'>");
 		});
 
 		this.irc.once("msg:preview", function(data) {
-			expect(data.preview.thumb).to.be.empty;
-			expect(data.preview.head).to.equal("test invalid image");
-			expect(data.preview.link).to.equal("http://localhost:9002/invalid-thumb");
+			expect(data.preview.thumb).to.equal("http://localhost:9002/real-test-image.png");
+			done();
+		});
+	});
+
+	it("should correctly resolve relative protocol", function(done) {
+		const message = this.irc.createMessage({
+			text: "http://localhost:9002/thumb-image-src"
+		});
+
+		link(this.irc, this.network.channels[0], message);
+
+		this.app.get("/thumb-image-src", function(req, res) {
+			res.send("<link rel='image_src' href='//localhost:9002/real-test-image.png'>");
+		});
+
+		this.irc.once("msg:preview", function(data) {
+			expect(data.preview.thumb).to.equal("http://localhost:9002/real-test-image.png");
+			done();
+		});
+	});
+
+	it("should resolve url correctly for relative url", function(done) {
+		const message = this.irc.createMessage({
+			text: "http://localhost:9002/relative-thumb"
+		});
+
+		link(this.irc, this.network.channels[0], message);
+
+		this.app.get("/relative-thumb", function(req, res) {
+			res.send("<title>test relative image</title><meta property='og:image' content='/real-test-image.png'>");
+		});
+
+		this.irc.once("msg:preview", function(data) {
+			expect(data.preview.thumb).to.equal("http://localhost:9002/real-test-image.png");
+			expect(data.preview.head).to.equal("test relative image");
+			expect(data.preview.link).to.equal("http://localhost:9002/relative-thumb");
 			done();
 		});
 	});