feature #29303 [Messenger] add welcome notice when running the comman…

…d (nicolas-grekas)

This PR was merged into the 4.3-dev branch.

Discussion
----------

[Messenger] add welcome notice when running the command

| Q             | A
| ------------- | ---
| Branch?       | master
| Bug fix?      | no
| New feature?  | yes
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | yes
| Fixed tickets | -
| License       | MIT
| Doc PR        | -

The current behavior of `./bin/console messenger:consume-messages` is totally silent: you run it and nothing visible happens.

Here is what is displayed with this PR:
![image](https://user-images.githubusercontent.com/243674/54235039-af0a6c80-4510-11e9-89d8-3c1c55e946c0.png)

Combined with #30539, it gives:
![image](https://user-images.githubusercontent.com/243674/54235156-ed079080-4510-11e9-9d4d-9f27c87e16e5.png)

Commits
-------

673b58b [Messenger] add welcome notice when running the command

src/Symfony/Component/Messenger/Command/ConsumeMessagesCommand.php

@@ -94,15 +94,15 @@ protected function configure(): void
      */
     protected function interact(InputInterface $input, OutputInterface $output)
     {
-        $style = new SymfonyStyle($input, $output);
+        $io = new SymfonyStyle($input, $output instanceof ConsoleOutputInterface ? $output->getErrorOutput() : $output);
 
         if ($this->receiverNames && !$this->receiverLocator->has($receiverName = $input->getArgument('receiver'))) {
             if (null === $receiverName) {
-                $style->block('Missing receiver argument.', null, 'error', ' ', true);
-                $input->setArgument('receiver', $style->choice('Select one of the available receivers', $this->receiverNames));
+                $io->block('Missing receiver argument.', null, 'error', ' ', true);
+                $input->setArgument('receiver', $io->choice('Select one of the available receivers', $this->receiverNames));
             } elseif ($alternatives = $this->findAlternatives($receiverName, $this->receiverNames)) {
-                $style->block(sprintf('Receiver "%s" is not defined.', $receiverName), null, 'error', ' ', true);
-                if ($style->confirm(sprintf('Do you want to receive from "%s" instead? ', $alternatives[0]), false)) {
+                $io->block(sprintf('Receiver "%s" is not defined.', $receiverName), null, 'error', ' ', true);
+                if ($io->confirm(sprintf('Do you want to receive from "%s" instead? ', $alternatives[0]), false)) {
                     $input->setArgument('receiver', $alternatives[0]);
                 }
             }
@@ -111,17 +111,17 @@ protected function interact(InputInterface $input, OutputInterface $output)
         $busName = $input->getOption('bus');
         if ($this->busNames && !$this->busLocator->has($busName)) {
             if (null === $busName) {
-                $style->block('Missing bus argument.', null, 'error', ' ', true);
-                $input->setOption('bus', $style->choice('Select one of the available buses', $this->busNames));
+                $io->block('Missing bus argument.', null, 'error', ' ', true);
+                $input->setOption('bus', $io->choice('Select one of the available buses', $this->busNames));
             } elseif ($alternatives = $this->findAlternatives($busName, $this->busNames)) {
-                $style->block(sprintf('Bus "%s" is not defined.', $busName), null, 'error', ' ', true);
+                $io->block(sprintf('Bus "%s" is not defined.', $busName), null, 'error', ' ', true);
 
                 if (1 === \count($alternatives)) {
-                    if ($style->confirm(sprintf('Do you want to dispatch to "%s" instead? ', $alternatives[0]), true)) {
+                    if ($io->confirm(sprintf('Do you want to dispatch to "%s" instead? ', $alternatives[0]), true)) {
                         $input->setOption('bus', $alternatives[0]);
                     }
                 } else {
-                    $input->setOption('bus', $style->choice('Did you mean one of the following buses instead?', $alternatives, $alternatives[0]));
+                    $input->setOption('bus', $io->choice('Did you mean one of the following buses instead?', $alternatives, $alternatives[0]));
                 }
             }
         }
@@ -143,18 +143,37 @@ protected function execute(InputInterface $input, OutputInterface $output): void
         $receiver = $this->receiverLocator->get($receiverName);
         $bus = $this->busLocator->get($busName);
 
+        $stopsWhen = [];
         if ($limit = $input->getOption('limit')) {
+            $stopsWhen[] = "processed {$limit} messages";
             $receiver = new StopWhenMessageCountIsExceededReceiver($receiver, $limit, $this->logger);
         }
 
         if ($memoryLimit = $input->getOption('memory-limit')) {
+            $stopsWhen[] = "exceeded {$memoryLimit} of memory";
             $receiver = new StopWhenMemoryUsageIsExceededReceiver($receiver, $this->convertToBytes($memoryLimit), $this->logger);
         }
 
         if ($timeLimit = $input->getOption('time-limit')) {
+            $stopsWhen[] = "been running for {$timeLimit}s";
             $receiver = new StopWhenTimeLimitIsReachedReceiver($receiver, $timeLimit, $this->logger);
         }
 
+        $io = new SymfonyStyle($input, $output instanceof ConsoleOutputInterface ? $output->getErrorOutput() : $output);
+        $io->success(sprintf('Consuming messages from transport "%s" on bus "%s".', $receiverName, $busName));
+
+        if ($stopsWhen) {
+            $last = array_pop($stopsWhen);
+            $stopsWhen = ($stopsWhen ? implode(', ', $stopsWhen).' or ' : '').$last;
+            $io->comment("The worker will automatically exit once it has {$stopsWhen}.");
+        }
+
+        $io->comment('Quit the worker with CONTROL-C.');
+
+        if (!$output->isDebug()) {
+            $io->comment('Re-run the command with a -vvv option to see logs about consumed messages.');
+        }
+
         $worker = new Worker($receiver, $bus);
         $worker->run();
     }
@@ -171,7 +190,7 @@ private function convertToBytes(string $memoryLimit): int
             $max = (int) $max;
         }
 
-        switch (substr($memoryLimit, -1)) {
+        switch (substr(rtrim($memoryLimit, 'b'), -1)) {
             case 't': $max *= 1024;
             // no break
             case 'g': $max *= 1024;

src/Symfony/Component/Messenger/Worker.php

@@ -18,6 +18,8 @@
  * @author Samuel Roze <samuel.roze@gmail.com>
  *
  * @experimental in 4.2
+ *
+ * @final
  */
 class Worker
 {