Make createThumbnailer async

lib/thumbnailer/index.js

@@ -32,30 +32,35 @@ function createReadStream(filePath) {
 }
 
 module.exports = function createThumbnailer(thumbnailFolder, pictureFolder, {width, height, quality}) {
-	return function getThumbnail(date, filename) {
+	return async function getThumbnail(date, filename) {
 		let thumbnailPath = path.join(thumbnailFolder, date, filename);
 
-		return Promise.try(() => {
-			return createReadStream(thumbnailPath);
-		}).catch({code: "ENOENT"}, (err) => {
-			/* Thumbnail does not exist yet, we need to create one. */
-
-			return Promise.try(() => {
-				return Promise.try(() => {
-					return fs.mkdirAsync(path.join(thumbnailFolder, date));
-				}).catch({code: "EEXIST"}, (err) => {
-					/* Ignore this type of error, it just means that the destination folder already exists. */
-				});
-			}).then(() => {
-				let resizer = gm(path.join(pictureFolder, date, filename)).noProfile().resize(width, height).quality(quality);
-				Promise.promisifyAll(resizer); // HACK
-				return resizer.writeAsync(thumbnailPath);
-			}).then(() => {
-				return createReadStream(thumbnailPath);
-			}).catch((err) => (/Command failed:/.test(err.message)), (err) => {
-				/* TODO: Chained errors */
-				throw new ThumbnailError(err.message);
-			});
-		});
-	}
+		try {
+			return await createReadStream(thumbnailPath);
+		} catch (err) {
+			if (err.code != 'ENOENT') {
+				throw err
+			}
+		}
+
+		/* Thumbnail does not exist yet, we need to create one. */
+
+		try {
+			await fs.mkdirAsync(path.join(thumbnailFolder, date));
+		} catch (err) {
+			/* Ignore this type of error, it just means that the destination folder already exists. */
+			if (err.code != 'EEXIST') {
+				throw err
+			}
+		}
+
+		let resizer = gm(path.join(pictureFolder, date, filename)).
+			noProfile().
+			resize(width, height).
+			quality(quality);
+		Promise.promisifyAll(resizer); // HACK
+		await resizer.writeAsync(thumbnailPath);
+
+		return await createReadStream(thumbnailPath);
+	};
 };