feat: refactor getSortedSetRange to allow big arrays

src/database/helpers.js

@@ -0,0 +1,31 @@
+'use strict';
+
+const helpers = module.exports;
+
+helpers.mergeBatch = function (batchData, start, stop, sort) {
+	function getFirst() {
+		let selectedArray = batchData[0];
+		for (let i = 1; i < batchData.length; i++) {
+			if (batchData[i].length && (
+				!selectedArray.length ||
+				(sort === 1 && batchData[i][0].score < selectedArray[0].score) ||
+				(sort === -1 && batchData[i][0].score > selectedArray[0].score)
+			)) {
+				selectedArray = batchData[i];
+			}
+		}
+		return selectedArray.length ? selectedArray.shift() : null;
+	}
+	let item = null;
+	const result = [];
+	var st = process.hrtime();
+	do {
+		item = getFirst(batchData);
+		if (item) {
+			result.push(item);
+		}
+	} while (item && (result.length < (stop - start + 1) || stop === -1));
+	process.profile('meeerge', st);
+
+	return result;
+};

src/database/mongo/sorted.js

@@ -1,9 +1,11 @@
 'use strict';
 
-var utils = require('../../utils');
+const utils = require('../../utils');
 
 module.exports = function (module) {
-	var helpers = require('./helpers');
+	const helpers = require('./helpers');
+	const dbHelpers = require('../helpers');
+
 	const util = require('util');
 	const sleep = util.promisify(setTimeout);
 
@@ -62,37 +64,54 @@ module.exports = function (module) {
 			fields.score = 0;
 		}
 
-		var reverse = false;
+		let reverse = false;
 		if (start === 0 && stop < -1) {
 			reverse = true;
 			sort *= -1;
 			start = Math.abs(stop + 1);
 			stop = -1;
 		} else if (start < 0 && stop > start) {
-			var tmp1 = Math.abs(stop + 1);
+			const tmp1 = Math.abs(stop + 1);
 			stop = Math.abs(start + 1);
 			start = tmp1;
 		}
 
-		var limit = stop - start + 1;
+		let limit = stop - start + 1;
 		if (limit <= 0) {
 			limit = 0;
 		}
 
-		let data = await module.client.collection('objects').find(query, { projection: fields })
-			.sort({ score: sort })
-			.skip(start)
-			.limit(limit)
-			.toArray();
+		let result = [];
+		async function doQuery(fields) {
+			return await module.client.collection('objects').find(query, { projection: fields })
+				.sort({ score: sort })
+				.skip(start)
+				.limit(limit)
+				.toArray();
+		}
+
+		if (isArray && key.length > 100) {
+			const batches = [];
+			const batch = require('../../batch');
+			await batch.processArray(key, async currentBatch => batches.push(currentBatch), { batch: 100 });
+			const batchData = await Promise.all(batches.map(async (batch) => {
+				query._key = { $in: batch };
+				return await doQuery({ _id: 0, _key: 0 });
+			}));
+
+			result = dbHelpers.mergeBatch(batchData, start, stop, sort);
+		} else {
+			result = await doQuery(fields);
+		}
 
 		if (reverse) {
-			data.reverse();
+			result.reverse();
 		}
 		if (!withScores) {
-			data = data.map(item => item.value);
+			result = result.map(item => item.value);
 		}
 
-		return data;
+		return result;
 	}
 
 	module.getSortedSetRangeByScore = async function (key, start, count, min, max) {

src/database/redis/sorted.js

@@ -3,6 +3,7 @@
 module.exports = function (module) {
 	const utils = require('../../utils');
 	const helpers = require('./helpers');
+	const dbHelpers = require('../helpers');
 
 	require('./sorted/add')(module);
 	require('./sorted/remove')(module);
@@ -26,20 +27,6 @@ module.exports = function (module) {
 	};
 
 	async function sortedSetRange(method, key, start, stop, withScores) {
-		function getFirst(mapped) {
-			let selectedArray = mapped[0];
-			for (let i = 1; i < mapped.length; i++) {
-				if (mapped[i].length && (
-					!selectedArray.length ||
-					(method === 'zrange' && mapped[i][0].score < selectedArray[0].score) ||
-					(method === 'zrevrange' && mapped[i][0].score > selectedArray[0].score)
-				)) {
-					selectedArray = mapped[i];
-				}
-			}
-			return selectedArray.length ? selectedArray.shift() : null;
-		}
-
 		if (Array.isArray(key)) {
 			if (!key.length) {
 				return [];
@@ -48,17 +35,9 @@ module.exports = function (module) {
 			key.forEach(key => batch[method]([key, start, stop, 'WITHSCORES']));
 			const data = await helpers.execBatch(batch);
 
-			const mapped = data.map(setData => helpers.zsetToObjectArray(setData));
+			const batchData = data.map(setData => helpers.zsetToObjectArray(setData));
 
-			let objects = [];
-			const count = stop - start + 1;
-			let item = null;
-			do {
-				item = getFirst(mapped);
-				if (item) {
-					objects.push(item);
-				}
-			} while (item && (objects.length < count || stop === -1));
+			let objects = dbHelpers.mergeBatch(batchData, start, stop, method === 'zrange' ? 1 : -1);
 
 			if (!withScores) {
 				objects = objects.map(item => item.value);

test/database/sorted.js

@@ -251,6 +251,35 @@ describe('Sorted Set methods', function () {
 			const data = await db.getSortedSetRevRange(['dupezset3', 'dupezset4'], 0, 1);
 			assert.deepStrictEqual(data, ['value5', 'value3']);
 		});
+
+		it('should work with big arrays (length > 100) ', async function () {
+			for (let i = 0; i < 400; i++) {
+				/* eslint-disable no-await-in-loop */
+				const bulkAdd = [];
+				for (let k = 0; k < 100; k++) {
+					bulkAdd.push(['testzset' + i, 1000000 + k + (i * 100), k + (i * 100)]);
+				}
+				await db.sortedSetAddBulk(bulkAdd);
+			}
+			const keys = [];
+			for (let i = 0; i < 400; i++) {
+				keys.push('testzset' + i);
+			}
+
+			let data = await db.getSortedSetRevRange(keys, 0, 3);
+			assert.deepStrictEqual(data, ['39999', '39998', '39997', '39996']);
+
+			data = await db.getSortedSetRevRangeWithScores(keys, 0, 3);
+			assert.deepStrictEqual(data, [
+				{ value: '39999', score: 1039999 },
+				{ value: '39998', score: 1039998 },
+				{ value: '39997', score: 1039997 },
+				{ value: '39996', score: 1039996 },
+			]);
+
+			data = await db.getSortedSetRevRange(keys, 0, -1);
+			assert.equal(data.length, 40000);
+		});
 	});
 
 	describe('getSortedSetRevRange()', function () {