Add download-only mode (#11041)

composer install --download-only to prime the cache/download archives but not do any actual of the actual installing

Fixes #11035

Co-authored-by: Jordi Boggiano <j.boggiano@seld.be>

doc/03-cli.md

@@ -107,6 +107,7 @@ resolution.
 * **--dry-run:** If you want to run through an installation without actually
   installing a package, you can use `--dry-run`. This will simulate the
   installation and show you what would happen.
+* **--download-only:** Download only, do not install packages.
 * **--dev:** Install packages listed in `require-dev` (this is the default behavior).
 * **--no-dev:** Skip installing packages listed in `require-dev`. The autoloader
   generation skips the `autoload-dev` rules. Also see [COMPOSER_NO_DEV](#composer-no-dev).

src/Composer/Command/InstallCommand.php

@@ -46,6 +46,7 @@ class InstallCommand extends BaseCommand
                 new InputOption('prefer-dist', null, InputOption::VALUE_NONE, 'Forces installation from package dist (default behavior).'),
                 new InputOption('prefer-install', null, InputOption::VALUE_REQUIRED, 'Forces installation from package dist|source|auto (auto chooses source for dev versions, dist for the rest).', null, $this->suggestPreferInstall()),
                 new InputOption('dry-run', null, InputOption::VALUE_NONE, 'Outputs the operations but will not execute anything (implicitly enables --verbose).'),
+                new InputOption('download-only', null, InputOption::VALUE_NONE, 'Download only, do not install packages.'),
                 new InputOption('dev', null, InputOption::VALUE_NONE, 'DEPRECATED: Enables installation of require-dev packages (enabled by default, only present for BC).'),
                 new InputOption('no-suggest', null, InputOption::VALUE_NONE, 'DEPRECATED: This flag does not exist anymore.'),
                 new InputOption('no-dev', null, InputOption::VALUE_NONE, 'Disables installation of require-dev packages.'),
@@ -124,6 +125,7 @@ EOT
 
         $install
             ->setDryRun($input->getOption('dry-run'))
+            ->setDownloadOnly($input->getOption('download-only'))
             ->setVerbose($input->getOption('verbose'))
             ->setPreferSource($preferSource)
             ->setPreferDist($preferDist)

src/Composer/Downloader/FileDownloader.php

@@ -307,9 +307,10 @@ class FileDownloader implements DownloaderInterface, ChangeReportInterface
         }
 
         $dirsToCleanUp = [
+            $path,
+            $this->config->get('vendor-dir').'/'.explode('/', $package->getPrettyName())[0],
             $this->config->get('vendor-dir').'/composer/',
             $this->config->get('vendor-dir'),
-            $path,
         ];
 
         if (isset($this->additionalCleanupPaths[$package->getName()])) {

src/Composer/Installer.php

@@ -148,6 +148,8 @@ class Installer
     /** @var bool */
     protected $dryRun = false;
     /** @var bool */
+    protected $downloadOnly = false;
+    /** @var bool */
     protected $verbose = false;
     /** @var bool */
     protected $update = false;
@@ -258,6 +260,10 @@ class Installer
             $this->mockLocalRepositories($this->repositoryManager);
         }
 
+        if ($this->downloadOnly) {
+            $this->dumpAutoloader = false;
+        }
+
         if ($this->update && !$this->install) {
             $this->dumpAutoloader = false;
         }
@@ -783,7 +789,7 @@ class Installer
 
         if ($this->executeOperations) {
             $localRepo->setDevPackageNames($this->locker->getDevPackageNames());
-            $this->installationManager->execute($localRepo, $localRepoTransaction->getOperations(), $this->devMode, $this->runScripts);
+            $this->installationManager->execute($localRepo, $localRepoTransaction->getOperations(), $this->devMode, $this->runScripts, $this->downloadOnly);
         } else {
             foreach ($localRepoTransaction->getOperations() as $operation) {
                 // output op, but alias op only in debug verbosity
@@ -1088,6 +1094,18 @@ class Installer
         return $this->dryRun;
     }
 
+    /**
+     * Whether to download only or not.
+     *
+     * @return Installer
+     */
+    public function setDownloadOnly(bool $downloadOnly = true): self
+    {
+        $this->downloadOnly = $downloadOnly;
+
+        return $this;
+    }
+
     /**
      * prefer source installation
      *

src/Composer/Installer/InstallationManager.php

@@ -176,40 +176,16 @@ class InstallationManager
      * @param OperationInterface[]         $operations   operations to execute
      * @param bool                         $devMode      whether the install is being run in dev mode
      * @param bool                         $runScripts   whether to dispatch script events
+     * @param bool                         $downloadOnly whether to only download packages
      */
-    public function execute(InstalledRepositoryInterface $repo, array $operations, bool $devMode = true, bool $runScripts = true): void
+    public function execute(InstalledRepositoryInterface $repo, array $operations, bool $devMode = true, bool $runScripts = true, bool $downloadOnly = false): void
     {
-        /** @var PromiseInterface[] */
+        /** @var array<callable(): ?PromiseInterface> */
         $cleanupPromises = [];
 
-        $loop = $this->loop;
+        $signalHandler = SignalHandler::create([SignalHandler::SIGINT, SignalHandler::SIGTERM, SignalHandler::SIGHUP], function (string $signal, SignalHandler $handler) use (&$cleanupPromises) {
-        $io = $this->io;
+            $this->io->writeError('Received '.$signal.', aborting', true, IOInterface::DEBUG);
-        $runCleanup = static function () use (&$cleanupPromises, $loop): void {
+            $this->runCleanup($cleanupPromises);
-            $promises = [];
-
-            $loop->abortJobs();
-
-            foreach ($cleanupPromises as $cleanup) {
-                $promises[] = new \React\Promise\Promise(static function ($resolve, $reject) use ($cleanup): void {
-                    $promise = $cleanup();
-                    if (!$promise instanceof PromiseInterface) {
-                        $resolve();
-                    } else {
-                        $promise->then(static function () use ($resolve): void {
-                            $resolve();
-                        });
-                    }
-                });
-            }
-
-            if (!empty($promises)) {
-                $loop->wait($promises);
-            }
-        };
-
-        $signalHandler = SignalHandler::create([SignalHandler::SIGINT, SignalHandler::SIGTERM, SignalHandler::SIGHUP], static function (string $signal, SignalHandler $handler) use ($io, $runCleanup) {
-            $io->writeError('Received '.$signal.', aborting', true, IOInterface::DEBUG);
-            $runCleanup();
             $handler->exitWithLastSignal();
         });
 
@@ -239,16 +215,20 @@ class InstallationManager
             }
 
             foreach ($batches as $batch) {
-                $this->downloadAndExecuteBatch($repo, $batch, $cleanupPromises, $devMode, $runScripts, $operations);
+                $this->downloadAndExecuteBatch($repo, $batch, $cleanupPromises, $devMode, $runScripts, $downloadOnly, $operations);
             }
         } catch (\Exception $e) {
-            $runCleanup();
+            $this->runCleanup($cleanupPromises);
 
             throw $e;
         } finally {
             $signalHandler->unregister();
         }
 
+        if ($downloadOnly) {
+            return;
+        }
+
         // do a last write so that we write the repository even if nothing changed
         // as that can trigger an update of some files like InstalledVersions.php if
         // running a new composer version
@@ -257,10 +237,10 @@ class InstallationManager
 
     /**
      * @param OperationInterface[] $operations    List of operations to execute in this batch
-     * @param PromiseInterface[] $cleanupPromises
+     * @param array<callable(): ?PromiseInterface> $cleanupPromises
      * @param OperationInterface[] $allOperations Complete list of operations to be executed in the install job, used for event listeners
      */
-    private function downloadAndExecuteBatch(InstalledRepositoryInterface $repo, array $operations, array &$cleanupPromises, bool $devMode, bool $runScripts, array $allOperations): void
+    private function downloadAndExecuteBatch(InstalledRepositoryInterface $repo, array $operations, array &$cleanupPromises, bool $devMode, bool $runScripts, bool $downloadOnly, array $allOperations): void
     {
         $promises = [];
 
@@ -283,11 +263,11 @@ class InstallationManager
             }
             $installer = $this->getInstaller($package->getType());
 
-            $cleanupPromises[$index] = static function () use ($opType, $installer, $package, $initialPackage) {
+            $cleanupPromises[$index] = static function () use ($opType, $installer, $package, $initialPackage): ?PromiseInterface {
                 // avoid calling cleanup if the download was not even initialized for a package
                 // as without installation source configured nothing will work
                 if (!$package->getInstallationSource()) {
-                    return;
+                    return \React\Promise\resolve();
                 }
 
                 return $installer->cleanup($opType, $package, $initialPackage);
@@ -306,6 +286,11 @@ class InstallationManager
             $this->waitOnPromises($promises);
         }
 
+        if ($downloadOnly) {
+            $this->runCleanup($cleanupPromises);
+            return;
+        }
+
         // execute operations in batches to make sure every plugin is installed in the
         // right order and activated before the packages depending on it are installed
         $batches = [];
@@ -337,7 +322,7 @@ class InstallationManager
 
     /**
      * @param OperationInterface[] $operations    List of operations to execute in this batch
-     * @param PromiseInterface[] $cleanupPromises
+     * @param array<callable(): ?PromiseInterface> $cleanupPromises
      * @param OperationInterface[] $allOperations Complete list of operations to be executed in the install job, used for event listeners
      */
     private function executeBatch(InstalledRepositoryInterface $repo, array $operations, array $cleanupPromises, bool $devMode, bool $runScripts, array $allOperations): void
@@ -368,6 +353,7 @@ class InstallationManager
                 $package = $operation->getPackage();
                 $initialPackage = null;
             }
+
             $installer = $this->getInstaller($package->getType());
 
             $eventName = [
@@ -451,6 +437,19 @@ class InstallationManager
         }
     }
 
+    /**
+     * Executes download operation.
+     *
+     * $param PackageInterface $package
+     */
+    public function download(PackageInterface $package): ?PromiseInterface
+    {
+        $installer = $this->getInstaller($package->getType());
+        $promise = $installer->cleanup("install", $package);
+
+        return $promise;
+    }
+
     /**
      * Executes install operation.
      *
@@ -637,4 +636,32 @@ class InstallationManager
             $this->notifiablePackages[$package->getNotificationUrl()][$package->getName()] = $package;
         }
     }
+
+    /**
+     * @param array<callable(): ?PromiseInterface> $cleanupPromises
+     * @return void
+     */
+    private function runCleanup(array $cleanupPromises): void
+    {
+        $promises = [];
+
+        $this->loop->abortJobs();
+
+        foreach ($cleanupPromises as $cleanup) {
+            $promises[] = new \React\Promise\Promise(static function ($resolve, $reject) use ($cleanup): void {
+                $promise = $cleanup();
+                if (!$promise instanceof PromiseInterface) {
+                    $resolve();
+                } else {
+                    $promise->then(static function () use ($resolve): void {
+                        $resolve();
+                    });
+                }
+            });
+        }
+
+        if (!empty($promises)) {
+            $this->loop->wait($promises);
+        }
+    }
 }

tests/Composer/Test/Mock/InstallationManagerMock.php

@@ -46,7 +46,7 @@ class InstallationManagerMock extends InstallationManager
     {
     }
 
-    public function execute(InstalledRepositoryInterface $repo, array $operations, $devMode = true, $runScripts = true): void
+    public function execute(InstalledRepositoryInterface $repo, array $operations, $devMode = true, $runScripts = true, $downloadOnly = false): void
     {
         foreach ($operations as $operation) {
             $method = $operation->getOperationType();