Added lastfm.trackScrobbleMany()

README.md

@@ -90,3 +90,28 @@ lastFm.userGetRecentTracks({
 ```
 
 When callback is passed, methods do not return a `promise`, instead return the LastFm instance the method was called on. This allows you to chain requests.
+
+## Utility methods
+
+These methods do not correspond to an exact API endpoint, but are abstractions of the already provided methods to provide easier usage.
+
+### `lastFm.trackScrobbleMany`
+
+This method takes an array of objects that match the `params` parameter accepted by `lastFm.trackScrobble`. It allows for multiple tracks to be submitted to the API in one request.
+
+```js
+lastFm.trackScrobbleMany([
+    {
+        "artist": "ARTIST",
+        "album": "ALBUM",
+        "track": "TRACK",
+        "timestamp": "TIMESTAMP"
+    },
+    {
+        "artist": "ARTIST",
+        "album": "ALBUM",
+        "track": "TRACK",
+        "timestamp": "TIMESTAMP"
+    }
+]);
+```

__test__/LastFm.test.js

@@ -841,6 +841,72 @@ describe("LastFm", () => {
 		});
 	});
 
+	test("scrobble many tracks", done => {
+		const lastFm = new LastFm({ apiKey, secret, sessionKey });
+
+		nock("http://ws.audioscrobbler.com")
+			.post("/2.0/", {
+				"api_key": apiKey,
+				"api_sig": /.+/u,
+				"format": "json",
+				"method": "track.scrobble",
+				"sk": sessionKey
+			})
+			.reply(200, { "status": "ok" });
+
+		lastFm.trackScrobbleMany([], (err, data) => {
+			expect(err).toBeNull();
+			expect(data).toEqual({ "status": "ok" });
+			done();
+		});
+	});
+
+	describe("trackScrobbleMany()", () => {
+		test("concatenate params array into single object, using array notation to distinguish each set of params, and call LastFm.trackScrobble() with that as the first argument", done => {
+			const lastFm = new LastFm({ apiKey, secret, sessionKey });
+			const spy = jest.spyOn(lastFm, "trackScrobble");
+			const params = [{ "param": "<value>" }, { "param": "<value>" }];
+
+			nock("http://ws.audioscrobbler.com")
+				.post("/2.0/")
+				.reply(200, { "status": "ok" });
+
+			lastFm.trackScrobbleMany(params, (err, data) => {
+				expect(err).toBeNull();
+				expect(data).toEqual({ "status": "ok" });
+				expect(spy).toBeCalledTimes(1);
+
+				const [firstCallArgs] = spy.mock.calls;
+				const [firstCallFirstArg] = firstCallArgs;
+
+				expect(JSON.stringify(firstCallFirstArg)).toBe("{\"param[1]\":\"<value>\",\"param[0]\":\"<value>\"}");
+				done();
+			});
+		});
+
+		test("if called with one params object, call LastFm.trackScrobble() with that as the first argument", done => {
+			const lastFm = new LastFm({ apiKey, secret, sessionKey });
+			const spy = jest.spyOn(lastFm, "trackScrobble");
+			const params = [{ "param": "<value>" }];
+
+			nock("http://ws.audioscrobbler.com")
+				.post("/2.0/")
+				.reply(200, { "status": "ok" });
+
+			lastFm.trackScrobbleMany(params, (err, data) => {
+				expect(err).toBeNull();
+				expect(data).toEqual({ "status": "ok" });
+				expect(spy).toBeCalledTimes(1);
+
+				const [firstCallArgs] = spy.mock.calls;
+				const [firstCallFirstArg] = firstCallArgs;
+
+				expect(JSON.stringify(firstCallFirstArg)).toBe("{\"param\":\"<value>\"}");
+				done();
+			});
+		});
+	});
+
 	test("search for a track", done => {
 		const lastFm = new LastFm({ apiKey, secret, sessionKey });
 

lib/LastFm.js

@@ -962,6 +962,39 @@ class LastFm {
 		return apiRequest || this;
 	}
 
+	/**
+	 * Scrobble many tracks
+	 * @param {Object[]} paramsArr
+	 * @param {string} paramsArr[].artist - Artist whose track to scrobble
+	 * @param {string} paramsArr[].track - Track to scobble
+	 * @param {string} [paramsArr[].album] - Album the track to scrobble is from
+	 * @param {string} [paramsArr[].albumArist] - Artist whose album the track to scrobble is from
+	 * @param {number} paramsArr[].timestamp - Timestamp to scrobble track at
+	 * @param {number} [paramsArr[].trackNumber] - Number of track to scrobble on the album
+	 * @param {number} [paramsArr[].duration] - Length of the track to scrobble in seconds
+	 * @param {(0|1)} [paramsArr[].chosenByUser] - Whether the user chose the track to scrobble
+	 * @param {string} [paramsArr.streamId] - Stream ID if track to scrobble is from Last.Fm radio
+	 * @param {callback} [callback]
+	 * @returns {(Promise|LastFm)}
+	 */
+
+	trackScrobbleMany(paramsArr, callback) {
+		if(paramsArr.length === 1) {
+			return this.trackScrobble(paramsArr[0], callback);
+		}
+
+		const paramsMany = {};
+		let i = paramsArr.length;
+
+		while(i--) {
+			for(const [param, value] of Object.entries(paramsArr[i])) {
+				paramsMany[`${param}[${i}]`] = value;
+			}
+		}
+
+		return this.trackScrobble(paramsMany, callback);
+	}
+
 	/**
 	 * Search for a track
 	 * @param {Object} params