[8.x] Add ability to clear queues

src/Illuminate/Contracts/Queue/ClearableQueue.php

@@ -0,0 +1,14 @@
+<?php
+
+namespace Illuminate\Contracts\Queue;
+
+interface ClearableQueue
+{
+    /**
+     * Clear all jobs from the queue.
+     *
+     * @param  string  $queue
+     * @return int
+     */
+    public function clear($queue);
+}

src/Illuminate/Foundation/Providers/ArtisanServiceProvider.php

@@ -57,6 +57,7 @@
 use Illuminate\Foundation\Console\ViewClearCommand;
 use Illuminate\Notifications\Console\NotificationTableCommand;
 use Illuminate\Queue\Console\BatchesTableCommand;
+use Illuminate\Queue\Console\ClearCommand as QueueClearCommand;
 use Illuminate\Queue\Console\FailedTableCommand;
 use Illuminate\Queue\Console\FlushFailedCommand as FlushFailedQueueCommand;
 use Illuminate\Queue\Console\ForgetFailedCommand as ForgetFailedQueueCommand;
@@ -96,6 +97,7 @@ class ArtisanServiceProvider extends ServiceProvider implements DeferrableProvid
         'Optimize' => 'command.optimize',
         'OptimizeClear' => 'command.optimize.clear',
         'PackageDiscover' => 'command.package.discover',
+        'QueueClear' => 'command.queue.clear',
         'QueueFailed' => 'command.queue.failed',
         'QueueFlush' => 'command.queue.flush',
         'QueueForget' => 'command.queue.forget',
@@ -712,6 +714,18 @@ protected function registerQueueWorkCommand()
         });
     }
 
+    /**
+     * Register the command.
+     *
+     * @return void
+     */
+    protected function registerQueueClearCommand()
+    {
+        $this->app->singleton('command.queue.clear', function () {
+            return new QueueClearCommand;
+        });
+    }
+
     /**
      * Register the command.
      *

src/Illuminate/Queue/Console/ClearCommand.php

@@ -0,0 +1,73 @@
+<?php
+
+namespace Illuminate\Queue\Console;
+
+use Illuminate\Console\Command;
+use Illuminate\Console\ConfirmableTrait;
+use Illuminate\Contracts\Queue\ClearableQueue;
+use ReflectionClass;
+
+class ClearCommand extends Command
+{
+    use ConfirmableTrait;
+
+    /**
+     * The console command name.
+     *
+     * @var string
+     */
+    protected $signature = 'queue:clear
+                            {connection? : The name of the queue connection to clear}
+                            {--queue= : The name of the queue to clear}';
+
+    /**
+     * The console command description.
+     *
+     * @var string
+     */
+    protected $description = 'Clear the queue';
+
+    /**
+     * Execute the console command.
+     *
+     * @return int|null
+     */
+    public function handle()
+    {
+        if (! $this->confirmToProceed()) {
+            return 1;
+        }
+
+        $connection = $this->argument('connection')
+                        ?: $this->laravel['config']['queue.default'];
+
+        // We need to get the right queue for the connection which is set in the queue
+        // configuration file for the application. We will pull it based on the set
+        // connection being run for the queue operation currently being executed.
+        $queueName = $this->getQueue($connection);
+        $queue = ($this->laravel['queue'])->connection($connection);
+
+        if ($queue instanceof ClearableQueue) {
+            $count = $queue->clear($queueName);
+
+            $this->line('<info>Cleared '.$count.' jobs from the '.$queueName.' queue</info> ');
+        } else {
+            $this->line('<error>Clearing queues is not supported on '.(new ReflectionClass($queue))->getShortName().'</error> ');
+        }
+
+        return 0;
+    }
+
+    /**
+     * Get the queue name to clear.
+     *
+     * @param  string  $connection
+     * @return string
+     */
+    protected function getQueue($connection)
+    {
+        return $this->option('queue') ?: $this->laravel['config']->get(
+            "queue.connections.{$connection}.queue", 'default'
+        );
+    }
+}

src/Illuminate/Queue/DatabaseQueue.php

@@ -2,14 +2,15 @@
 
 namespace Illuminate\Queue;
 
+use Illuminate\Contracts\Queue\ClearableQueue;
 use Illuminate\Contracts\Queue\Queue as QueueContract;
 use Illuminate\Database\Connection;
 use Illuminate\Queue\Jobs\DatabaseJob;
 use Illuminate\Queue\Jobs\DatabaseJobRecord;
 use Illuminate\Support\Carbon;
 use PDO;
 
-class DatabaseQueue extends Queue implements QueueContract
+class DatabaseQueue extends Queue implements QueueContract, ClearableQueue
 {
     /**
      * The database connection instance.
@@ -303,6 +304,19 @@ protected function markJobAsReserved($job)
         return $job;
     }
 
+    /**
+     * Clear all jobs from the queue.
+     *
+     * @param  string  $queue
+     * @return int
+     */
+    public function clear($queue)
+    {
+        return $this->database->table($this->table)
+                    ->where('queue', $this->getQueue($queue))
+                    ->delete();
+    }
+
     /**
      * Delete a reserved job from the queue.
      *

src/Illuminate/Queue/LuaScripts.php

@@ -20,6 +20,24 @@ public static function size()
 LUA;
     }
 
+    /**
+     * Get the Lua script for clearing the queue.
+     *
+     * KEYS[1] - The name of the primary queue
+     * KEYS[2] - The name of the "delayed" queue
+     * KEYS[3] - The name of the "reserved" queue
+     *
+     * @return string
+     */
+    public static function clear()
+    {
+        return <<<'LUA'
+local size = redis.call('llen', KEYS[1]) + redis.call('zcard', KEYS[2]) + redis.call('zcard', KEYS[3])
+redis.call('del', KEYS[1], KEYS[2], KEYS[3])
+return size
+LUA;
+    }
+
     /**
      * Get the Lua script for pushing jobs onto the queue.
      *

src/Illuminate/Queue/RedisQueue.php

@@ -2,12 +2,13 @@
 
 namespace Illuminate\Queue;
 
+use Illuminate\Contracts\Queue\ClearableQueue;
 use Illuminate\Contracts\Queue\Queue as QueueContract;
 use Illuminate\Contracts\Redis\Factory as Redis;
 use Illuminate\Queue\Jobs\RedisJob;
 use Illuminate\Support\Str;
 
-class RedisQueue extends Queue implements QueueContract
+class RedisQueue extends Queue implements QueueContract, ClearableQueue
 {
     /**
      * The Redis factory implementation.
@@ -256,6 +257,21 @@ protected function retrieveNextJob($queue, $block = true)
         return [$job, $reserved];
     }
 
+    /**
+     * Clear all jobs from the queue.
+     *
+     * @param  string  $queue
+     * @return int
+     */
+    public function clear($queue)
+    {
+        $queue = $this->getQueue($queue);
+
+        return $this->getConnection()->eval(
+            LuaScripts::clear(), 3, $queue, $queue.':delayed', $queue.':reserved'
+        );
+    }
+
     /**
      * Delete a reserved job from the queue.
      *

tests/Queue/QueueDatabaseQueueIntegrationTest.php

@@ -147,6 +147,35 @@ public function testPoppedJobsIncrementAttempts()
         $this->assertEquals(1, $popped_job->attempts(), 'The "attempts" attribute of the Job object was not updated by pop!');
     }
 
+    /**
+     * Test that the queue can be cleared.
+     */
+    public function testThatQueueCanBeCleared()
+    {
+        $this->connection()
+            ->table('jobs')
+            ->insert([[
+                'id' => 1,
+                'queue' => $mock_queue_name = 'mock_queue_name',
+                'payload' => 'mock_payload',
+                'attempts' => 0,
+                'reserved_at' => Carbon::now()->addDay()->getTimestamp(),
+                'available_at' => Carbon::now()->subDay()->getTimestamp(),
+                'created_at' => Carbon::now()->getTimestamp(),
+            ], [
+                'id' => 2,
+                'queue' => $mock_queue_name,
+                'payload' => 'mock_payload 2',
+                'attempts' => 0,
+                'reserved_at' => null,
+                'available_at' => Carbon::now()->subSeconds(1)->getTimestamp(),
+                'created_at' => Carbon::now()->getTimestamp(),
+            ]]);
+
+        $this->assertEquals(2, $this->queue->clear($mock_queue_name));
+        $this->assertEquals(0, $this->queue->size());
+    }
+
     /**
      * Test that jobs that are not reserved and have an available_at value in the future, are not popped.
      */

tests/Queue/RedisQueueIntegrationTest.php

@@ -414,6 +414,25 @@ public function testDelete($driver)
         $this->assertNull($this->queue->pop());
     }
 
+    /**
+     * @dataProvider redisDriverProvider
+     *
+     * @param  string  $driver
+     */
+    public function testClear($driver)
+    {
+        $this->setQueue($driver);
+
+        $job1 = new RedisQueueIntegrationTestJob(30);
+        $job2 = new RedisQueueIntegrationTestJob(40);
+
+        $this->queue->push($job1);
+        $this->queue->push($job2);
+
+        $this->assertEquals(2, $this->queue->clear(null));
+        $this->assertEquals(0, $this->queue->size());
+    }
+
     /**
      * @dataProvider redisDriverProvider
      *