Prevent artifact key collision when builds are restarted

Summary: Ref T1049.  Because we no longer destroy artifacts when builds are restarted, we need the build generation number to be part of the artifact key, otherwise we get collisions when restarting builds that contain build steps that emit artifacts.

Test Plan: Ran it with a build plan of "Lease Host" and "Run Command", no longer got an artifact key crash.

Reviewers: #blessed_reviewers, epriestley

Reviewed By: #blessed_reviewers, epriestley

Subscribers: epriestley, Korvin

Maniphest Tasks: T1049

Differential Revision: https://secure.phabricator.com/D10336

src/applications/harbormaster/query/HarbormasterBuildArtifactQuery.php

@@ -8,6 +8,7 @@ final class HarbormasterBuildArtifactQuery
   private $artifactTypes;
   private $artifactKeys;
   private $keyBuildPHID;
+  private $keyBuildGeneration;
 
   public function withIDs(array $ids) {
     $this->ids = $ids;
@@ -24,8 +25,12 @@ final class HarbormasterBuildArtifactQuery
     return $this;
   }
 
-  public function withArtifactKeys($build_phid, array $artifact_keys) {
+  public function withArtifactKeys(
+    $build_phid,
+    $build_gen,
+    array $artifact_keys) {
     $this->keyBuildPHID = $build_phid;
+    $this->keyBuildGeneration = $build_gen;
     $this->artifactKeys = $artifact_keys;
     return $this;
   }
@@ -98,7 +103,7 @@ final class HarbormasterBuildArtifactQuery
       $indexes = array();
       foreach ($this->artifactKeys as $key) {
         $indexes[] = PhabricatorHash::digestForIndex(
-          $this->keyBuildPHID.$key);
+          $this->keyBuildPHID.$this->keyBuildGeneration.$key);
       }
 
       $where[] = qsprintf(

src/applications/harbormaster/storage/build/HarbormasterBuild.php

@@ -213,7 +213,10 @@ final class HarbormasterBuild extends HarbormasterDAO
 
     $artifact =
       HarbormasterBuildArtifact::initializeNewBuildArtifact($build_target);
-    $artifact->setArtifactKey($this->getPHID(), $artifact_key);
+    $artifact->setArtifactKey(
+      $this->getPHID(),
+      $this->getBuildGeneration(),
+      $artifact_key);
     $artifact->setArtifactType($artifact_type);
     $artifact->save();
     return $artifact;
@@ -224,6 +227,7 @@ final class HarbormasterBuild extends HarbormasterDAO
       ->setViewer(PhabricatorUser::getOmnipotentUser())
       ->withArtifactKeys(
         $this->getPHID(),
+        $this->getBuildGeneration(),
         array($name))
       ->executeOne();
     if ($artifact === null) {

src/applications/harbormaster/storage/build/HarbormasterBuildArtifact.php

@@ -38,9 +38,9 @@ final class HarbormasterBuildArtifact extends HarbormasterDAO
     return $this->assertAttached($this->buildTarget);
   }
 
-  public function setArtifactKey($build_phid, $key) {
+  public function setArtifactKey($build_phid, $build_gen, $key) {
     $this->artifactIndex =
-      PhabricatorHash::digestForIndex($build_phid.$key);
+      PhabricatorHash::digestForIndex($build_phid.$build_gen.$key);
     $this->artifactKey = $key;
     return $this;
   }