Extend Sorted Set support by implementing ZRANDMEMBER command (#825)

* Added support for ZRANDMEMBER, added test coverage

* Changed key to more specific on exception testing

Co-authored-by: Vladislav <vladislav@Admins-MacBook-Pro.local>

src/ClientContextInterface.php

@@ -112,6 +112,7 @@ use Predis\Command\CommandInterface;
  * @method $this zincrby($key, $increment, $member)
  * @method $this zinterstore($destination, array|string $keys, array $options = null)
  * @method $this zmscore(string $key, string ...$member)
+ * @method $this zrandmember(string $key, int $count = 1, bool $withScores = false)
  * @method $this zrange($key, $start, $stop, array $options = null)
  * @method $this zrangebyscore($key, $min, $max, array $options = null)
  * @method $this zrank($key, $member)

src/ClientInterface.php

@@ -130,6 +130,7 @@ use Predis\Response\Status;
  * @method array             zmscore(string $key, string ...$member)
  * @method array             zpopmin(string $key, int $count = 1)
  * @method array             zpopmax(string $key, int $count = 1)
+ * @method mixed             zrandmember(string $key, int $count = 1, bool $withScores = false)
  * @method array             zrange(string $key, int|string $start, int|string $stop, array $options = null)
  * @method array             zrangebyscore(string $key, int|string $min, int|string $max, array $options = null)
  * @method int|null          zrank(string $key, string $member)

src/Command/Redis/ZRANDMEMBER.php

@@ -0,0 +1,39 @@
+<?php
+
+namespace Predis\Command\Redis;
+
+use Predis\Command\Command as RedisCommand;
+
+/**
+ * @link https://redis.io/commands/zrandmember/
+ *
+ * Return a random element from the sorted set value stored at key.
+ *
+ * If the provided count argument is positive, return an array of distinct elements.
+ *
+ * If called with a negative count, the behavior changes and the command
+ * is allowed to return the same element multiple times.
+ *
+ * @version >= 6.2.0
+ */
+class ZRANDMEMBER extends RedisCommand
+{
+
+    public function getId()
+    {
+        return 'ZRANDMEMBER';
+    }
+
+    public function setArguments(array $arguments)
+    {
+        $withScores = (count($arguments) === 3)
+            ? array_pop($arguments)
+            : false;
+
+        if (is_bool($withScores) && $withScores) {
+            $arguments[] = 'WITHSCORES';
+        }
+
+        parent::setArguments($arguments);
+    }
+}

tests/Predis/Command/Redis/ZRANDMEMBER_test.php

@@ -0,0 +1,131 @@
+<?php
+
+namespace Predis\Command\Redis;
+
+use Predis\Response\ServerException;
+
+class ZRANDMEMBER_test extends PredisCommandTestCase
+{
+
+    /**
+     * @inheritDoc
+     */
+    protected function getExpectedCommand(): string
+    {
+        return ZRANDMEMBER::class;
+    }
+
+    /**
+     * @inheritDoc
+     */
+    protected function getExpectedId(): string
+    {
+       return 'ZRANDMEMBER';
+    }
+
+    /**
+     * @group disconnected
+     * @dataProvider argumentsProvider
+     */
+    public function testFilterArguments(array $actualArguments, array $expectedArguments): void
+    {
+        $command = $this->getCommand();
+        $command->setArguments($actualArguments);
+
+        $this->assertSame($expectedArguments, $command->getArguments());
+    }
+
+    /**
+     * @group disconnected
+     */
+    public function testParseResponse(): void
+    {
+        $this->assertSame(1, $this->getCommand()->parseResponse(1));
+    }
+
+    /**
+     * @group connected
+     * @param string $key
+     * @param int $count
+     * @param array $membersDictionary
+     * @param array $expectedResponse
+     * @param bool $withScores
+     * @return void
+     * @dataProvider membersProvider
+     * @requiresRedisVersion >= 6.2.0
+     */
+    public function testReturnsRandomMembersFromSortedSet(
+        string $key,
+        int $count,
+        array $membersDictionary,
+        array $expectedResponse,
+        bool $withScores
+    ): void {
+        $redis = $this->getClient();
+        $notExpectedKey = 'not_expected';
+
+        $redis->zadd($key, ...$membersDictionary);
+        $this->assertSameValues($redis->zrandmember($key, $count, $withScores), $expectedResponse);
+        $this->assertNull($redis->zrandmember($notExpectedKey));
+    }
+
+    /**
+     * @group connected
+     * @requiresRedisVersion >= 6.2.0
+     */
+    public function testThrowsExceptionOnWrongType(): void
+    {
+        $this->expectException(ServerException::class);
+        $this->expectExceptionMessage('Operation against a key holding the wrong kind of value');
+
+        $redis = $this->getClient();
+
+        $redis->set('zrandmember_foo', 'bar');
+        $redis->zrandmember('zrandmember_foo', 1, true);
+    }
+
+    public function argumentsProvider(): array
+    {
+        return [
+            'with scores' => [['zset', 5, 'withScores' => true], ['zset', 5, 'WITHSCORES']],
+            'without scores' => [['zset', 5], ['zset', 5]],
+            'without scores - false value' => [['zset', 5, 'withScores' => false], ['zset', 5]],
+        ];
+    }
+
+    public function membersProvider(): array
+    {
+        return [
+            'one member - without score' => ['test-zset', 1, [1, 'member1'], ['member1'], false],
+            'multiple members - positive count - without score' => [
+                'test-zset',
+                2,
+                [1, 'member1', 2, 'member2'],
+                ['member1', 'member2'],
+                false
+            ],
+            'multiple members - negative count - without score' => [
+                'test-zset',
+                -2,
+                [1, 'member1'],
+                ['member1', 'member1'],
+                false
+            ],
+            'one member - with score' => ['test-zset', 1, [1, 'member1'], ['member1', 1], true],
+            'multiple members - positive count - with score' => [
+                'test-zset',
+                2,
+                [1, 'member1', 2, 'member2'],
+                ['member1', 1, 'member2', 2],
+                true
+            ],
+            'multiple members - negative count - with score' => [
+                'test-zset',
+                -2,
+                [1, 'member1'],
+                ['member1', 1, 'member1', 1],
+                true
+            ],
+        ];
+    }
+}