fix #1970 - add support for RESTORE (#2535)

* - Added RESTORE functionality

* add FIRST_KEY_INDEX, fix tests, clean example, add example to examples table

* use returnBuffers in test

---------

Co-authored-by: Leibale Eidelman <me@leibale.com>

examples/README.md

@@ -3,7 +3,7 @@
 This folder contains example scripts showing how to use Node Redis in different scenarios.
 
 | File Name                                | Description                                                                                                                                          |
-| ---------------------------------------- | ---------------------------------------------------------------------------------------------------------------------------------------------------- |
+|------------------------------------------|------------------------------------------------------------------------------------------------------------------------------------------------------|
 | `blocking-list-pop.js`                   | Block until an element is pushed to a list.                                                                                                          |
 | `bloom-filter.js`                        | Space efficient set membership checks with a [Bloom Filter](https://en.wikipedia.org/wiki/Bloom_filter) using [RedisBloom](https://redisbloom.io).   |
 | `check-connection-status.js`             | Check the client's connection status.                                                                                                                |
@@ -12,6 +12,7 @@ This folder contains example scripts showing how to use Node Redis in different
 | `connect-to-cluster.js`                  | Connect to a Redis cluster.                                                                                                                          |
 | `count-min-sketch.js`                    | Estimate the frequency of a given event using the [RedisBloom](https://redisbloom.io) Count-Min Sketch.                                              |
 | `cuckoo-filter.js`                       | Space efficient set membership checks with a [Cuckoo Filter](https://en.wikipedia.org/wiki/Cuckoo_filter) using [RedisBloom](https://redisbloom.io). |
+| `dump-and-restore.js`                    | Demonstrates the use of the [`DUMP`](https://redis.io/commands/dump/) and [`RESTORE`](https://redis.io/commands/restore/) commands                   |
 | `get-server-time.js`                     | Get the time from the Redis server.                                                                                                                  |
 | `hyperloglog.js`                         | Showing use of Hyperloglog commands [PFADD, PFCOUNT and PFMERGE](https://redis.io/commands/?group=hyperloglog).                                      |
 | `lua-multi-incr.js`                      | Define a custom lua script that allows you to perform INCRBY on multiple keys.                                                                       |

examples/dump-and-restore.js

@@ -0,0 +1,22 @@
+// This example demonstrates the use of the DUMP and RESTORE commands
+
+import { commandOptions, createClient } from 'redis';
+
+const client = createClient();
+await client.connect();
+
+// DUMP a specific key into a local variable
+const dump = await client.dump(
+    commandOptions({ returnBuffers: true }),
+    'source'
+);
+
+// RESTORE into a new key
+await client.restore('destination', 0, dump);
+
+// RESTORE and REPLACE an existing key
+await client.restore('destination', 0, dump, {
+    REPLACE: true
+});
+
+await client.quit();

packages/client/lib/cluster/commands.ts

@@ -110,6 +110,7 @@ import * as PTTL from '../commands/PTTL';
 import * as PUBLISH from '../commands/PUBLISH';
 import * as RENAME from '../commands/RENAME';
 import * as RENAMENX from '../commands/RENAMENX';
+import * as RESTORE from '../commands/RESTORE';
 import * as RPOP_COUNT from '../commands/RPOP_COUNT';
 import * as RPOP from '../commands/RPOP';
 import * as RPOPLPUSH from '../commands/RPOPLPUSH';
@@ -434,6 +435,8 @@ export default {
     rename: RENAME,
     RENAMENX,
     renameNX: RENAMENX,
+    RESTORE,
+    restore: RESTORE,
     RPOP_COUNT,
     rPopCount: RPOP_COUNT,
     RPOP,

packages/client/lib/commands/RESTORE.spec.ts

@@ -0,0 +1,74 @@
+import { strict as assert } from 'assert';
+import testUtils, { GLOBAL } from '../test-utils';
+import { transformArguments } from './RESTORE';
+
+describe('RESTORE', () => {
+    describe('transformArguments', () => {
+        it('simple', () => {
+            assert.deepEqual(
+                transformArguments('key', 0, 'value'),
+                ['RESTORE', 'key', '0', 'value']
+            );
+        });
+
+        it('with REPLACE', () => {
+            assert.deepEqual(
+                transformArguments('key', 0, 'value', {
+                    REPLACE: true
+                }),
+                ['RESTORE', 'key', '0', 'value', 'REPLACE']
+            );
+        });
+
+        it('with ABSTTL', () => {
+            assert.deepEqual(
+                transformArguments('key', 0, 'value', {
+                    ABSTTL: true
+                }),
+                ['RESTORE', 'key', '0', 'value', 'ABSTTL']
+            );
+        });
+
+        it('with IDLETIME', () => {
+            assert.deepEqual(
+                transformArguments('key', 0, 'value', {
+                    IDLETIME: 1
+                }),
+                ['RESTORE', 'key', '0', 'value', 'IDLETIME', '1']
+            );
+        });
+
+        it('with FREQ', () => {
+            assert.deepEqual(
+                transformArguments('key', 0, 'value', {
+                    FREQ: 1
+                }),
+                ['RESTORE', 'key', '0', 'value', 'FREQ', '1']
+            );
+        });
+
+        it('with REPLACE, ABSTTL, IDLETIME and FREQ', () => {
+            assert.deepEqual(
+                transformArguments('key', 0, 'value', {
+                    REPLACE: true,
+                    ABSTTL: true,
+                    IDLETIME: 1,
+                    FREQ: 2
+                }),
+                ['RESTORE', 'key', '0', 'value', 'REPLACE', 'ABSTTL', 'IDLETIME', '1', 'FREQ', '2']
+            );
+        });
+    });
+
+    testUtils.testWithClient('client.restore', async client => {
+        const [, dump] = await Promise.all([
+            client.set('source', 'value'),
+            client.dump(client.commandOptions({ returnBuffers: true }), 'source')
+        ]);
+
+        assert.equal(
+            await client.restore('destination', 0, dump),
+            'OK'
+        );
+    }, GLOBAL.SERVERS.OPEN);
+});

packages/client/lib/commands/RESTORE.ts

@@ -0,0 +1,39 @@
+import { RedisCommandArgument, RedisCommandArguments } from '.';
+
+export const FIRST_KEY_INDEX = 1;
+
+interface RestoreOptions {
+    REPLACE?: true;
+    ABSTTL?: true;
+    IDLETIME?: number;
+    FREQ?: number;
+}
+
+export function transformArguments(
+    key: RedisCommandArgument,
+    ttl: number,
+    serializedValue: RedisCommandArgument,
+    options?: RestoreOptions
+): RedisCommandArguments {
+    const args =  ['RESTORE', key, ttl.toString(), serializedValue];
+
+    if (options?.REPLACE) {
+        args.push('REPLACE');
+    }
+
+    if (options?.ABSTTL) {
+        args.push('ABSTTL');
+    }
+
+    if (options?.IDLETIME) {
+        args.push('IDLETIME', options.IDLETIME.toString());
+    }
+
+    if (options?.FREQ) {
+        args.push('FREQ', options.FREQ.toString());
+    }
+
+    return args;
+}
+
+export declare function transformReply(): 'OK';