1 files changed, 257 insertions, 0 deletions
diff --git a/java/com/google/gerrit/server/ApprovalCopier.java b/java/com/google/gerrit/server/ApprovalCopier.java
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+++ b/java/com/google/gerrit/server/ApprovalCopier.java
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+// Copyright (C) 2014 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.google.gerrit.server;
+
+import static com.google.common.base.Preconditions.checkArgument;
+import static java.util.Objects.requireNonNull;
+
+import com.google.common.collect.HashBasedTable;
+import com.google.common.collect.ListMultimap;
+import com.google.common.collect.Table;
+import com.google.gerrit.common.Nullable;
+import com.google.gerrit.common.data.LabelType;
+import com.google.gerrit.extensions.client.ChangeKind;
+import com.google.gerrit.reviewdb.client.Account;
+import com.google.gerrit.reviewdb.client.PatchSet;
+import com.google.gerrit.reviewdb.client.PatchSetApproval;
+import com.google.gerrit.reviewdb.server.ReviewDb;
+import com.google.gerrit.server.change.ChangeKindCache;
+import com.google.gerrit.server.change.LabelNormalizer;
+import com.google.gerrit.server.notedb.ChangeNotes;
+import com.google.gerrit.server.notedb.NoteDbChangeState.PrimaryStorage;
+import com.google.gerrit.server.project.ProjectCache;
+import com.google.gerrit.server.project.ProjectState;
+import com.google.gerrit.server.query.change.ChangeData;
+import com.google.gwtorm.server.OrmException;
+import com.google.inject.Inject;
+import com.google.inject.Singleton;
+import java.io.IOException;
+import java.util.Collection;
+import java.util.Collections;
+import java.util.List;
+import java.util.TreeMap;
+import org.eclipse.jgit.lib.Config;
+import org.eclipse.jgit.lib.ObjectId;
+import org.eclipse.jgit.revwalk.RevWalk;
+
+/**
+ * Copies approvals between patch sets.
+ *
+ * <p>The result of a copy may either be stored, as when stamping approvals in the database at
+ * submit time, or refreshed on demand, as when reading approvals from the NoteDb.
+ */
+@Singleton
+public class ApprovalCopier {
+  private final ProjectCache projectCache;
+  private final ChangeKindCache changeKindCache;
+  private final LabelNormalizer labelNormalizer;
+  private final ChangeData.Factory changeDataFactory;
+  private final PatchSetUtil psUtil;
+
+  @Inject
+  ApprovalCopier(
+      ProjectCache projectCache,
+      ChangeKindCache changeKindCache,
+      LabelNormalizer labelNormalizer,
+      ChangeData.Factory changeDataFactory,
+      PatchSetUtil psUtil) {
+    this.projectCache = projectCache;
+    this.changeKindCache = changeKindCache;
+    this.labelNormalizer = labelNormalizer;
+    this.changeDataFactory = changeDataFactory;
+    this.psUtil = psUtil;
+  }
+
+  /**
+   * Apply approval copy settings from prior PatchSets to a new PatchSet.
+   *
+   * @param db review database.
+   * @param notes change notes for user uploading PatchSet
+   * @param ps new PatchSet
+   * @param rw open walk that can read the patch set commit; null to open the repo on demand.
+   * @param repoConfig repo config used for change kind detection; null to read from repo on demand.
+   * @throws OrmException
+   */
+  public void copyInReviewDb(
+      ReviewDb db,
+      ChangeNotes notes,
+      PatchSet ps,
+      @Nullable RevWalk rw,
+      @Nullable Config repoConfig)
+      throws OrmException {
+    copyInReviewDb(db, notes, ps, rw, repoConfig, Collections.emptyList());
+  }
+
+  /**
+   * Apply approval copy settings from prior PatchSets to a new PatchSet.
+   *
+   * @param db review database.
+   * @param notes change notes for user uploading PatchSet
+   * @param ps new PatchSet
+   * @param rw open walk that can read the patch set commit; null to open the repo on demand.
+   * @param repoConfig repo config used for change kind detection; null to read from repo on demand.
+   * @param dontCopy PatchSetApprovals indicating which (account, label) pairs should not be copied
+   * @throws OrmException
+   */
+  public void copyInReviewDb(
+      ReviewDb db,
+      ChangeNotes notes,
+      PatchSet ps,
+      @Nullable RevWalk rw,
+      @Nullable Config repoConfig,
+      Iterable<PatchSetApproval> dontCopy)
+      throws OrmException {
+    if (PrimaryStorage.of(notes.getChange()) == PrimaryStorage.REVIEW_DB) {
+      db.patchSetApprovals().insert(getForPatchSet(db, notes, ps, rw, repoConfig, dontCopy));
+    }
+  }
+
+  Iterable<PatchSetApproval> getForPatchSet(
+      ReviewDb db,
+      ChangeNotes notes,
+      PatchSet.Id psId,
+      @Nullable RevWalk rw,
+      @Nullable Config repoConfig)
+      throws OrmException {
+    return getForPatchSet(
+        db, notes, psId, rw, repoConfig, Collections.<PatchSetApproval>emptyList());
+  }
+
+  Iterable<PatchSetApproval> getForPatchSet(
+      ReviewDb db,
+      ChangeNotes notes,
+      PatchSet.Id psId,
+      @Nullable RevWalk rw,
+      @Nullable Config repoConfig,
+      Iterable<PatchSetApproval> dontCopy)
+      throws OrmException {
+    PatchSet ps = psUtil.get(db, notes, psId);
+    if (ps == null) {
+      return Collections.emptyList();
+    }
+    return getForPatchSet(db, notes, ps, rw, repoConfig, dontCopy);
+  }
+
+  private Iterable<PatchSetApproval> getForPatchSet(
+      ReviewDb db,
+      ChangeNotes notes,
+      PatchSet ps,
+      @Nullable RevWalk rw,
+      @Nullable Config repoConfig,
+      Iterable<PatchSetApproval> dontCopy)
+      throws OrmException {
+    requireNonNull(ps, "ps should not be null");
+    ChangeData cd = changeDataFactory.create(db, notes);
+    try {
+      ProjectState project = projectCache.checkedGet(cd.change().getDest().getParentKey());
+      ListMultimap<PatchSet.Id, PatchSetApproval> all = cd.approvals();
+      requireNonNull(all, "all should not be null");
+
+      Table<String, Account.Id, PatchSetApproval> wontCopy = HashBasedTable.create();
+      for (PatchSetApproval psa : dontCopy) {
+        wontCopy.put(psa.getLabel(), psa.getAccountId(), psa);
+      }
+
+      Table<String, Account.Id, PatchSetApproval> byUser = HashBasedTable.create();
+      for (PatchSetApproval psa : all.get(ps.getId())) {
+        if (!wontCopy.contains(psa.getLabel(), psa.getAccountId())) {
+          byUser.put(psa.getLabel(), psa.getAccountId(), psa);
+        }
+      }
+
+      TreeMap<Integer, PatchSet> patchSets = getPatchSets(cd);
+
+      // Walk patch sets strictly less than current in descending order.
+      Collection<PatchSet> allPrior =
+          patchSets.descendingMap().tailMap(ps.getId().get(), false).values();
+      for (PatchSet priorPs : allPrior) {
+        List<PatchSetApproval> priorApprovals = all.get(priorPs.getId());
+        if (priorApprovals.isEmpty()) {
+          continue;
+        }
+
+        ChangeKind kind =
+            changeKindCache.getChangeKind(
+                project.getNameKey(),
+                rw,
+                repoConfig,
+                ObjectId.fromString(priorPs.getRevision().get()),
+                ObjectId.fromString(ps.getRevision().get()));
+
+        for (PatchSetApproval psa : priorApprovals) {
+          if (wontCopy.contains(psa.getLabel(), psa.getAccountId())) {
+            continue;
+          }
+          if (byUser.contains(psa.getLabel(), psa.getAccountId())) {
+            continue;
+          }
+          if (!canCopy(project, psa, ps.getId(), kind)) {
+            wontCopy.put(psa.getLabel(), psa.getAccountId(), psa);
+            continue;
+          }
+          byUser.put(psa.getLabel(), psa.getAccountId(), copy(psa, ps.getId()));
+        }
+      }
+      return labelNormalizer.normalize(notes, byUser.values()).getNormalized();
+    } catch (IOException e) {
+      throw new OrmException(e);
+    }
+  }
+
+  private static TreeMap<Integer, PatchSet> getPatchSets(ChangeData cd) throws OrmException {
+    Collection<PatchSet> patchSets = cd.patchSets();
+    TreeMap<Integer, PatchSet> result = new TreeMap<>();
+    for (PatchSet ps : patchSets) {
+      result.put(ps.getId().get(), ps);
+    }
+    return result;
+  }
+
+  private static boolean canCopy(
+      ProjectState project, PatchSetApproval psa, PatchSet.Id psId, ChangeKind kind) {
+    int n = psa.getKey().getParentKey().get();
+    checkArgument(n != psId.get());
+    LabelType type = project.getLabelTypes().byLabel(psa.getLabelId());
+    if (type == null) {
+      return false;
+    } else if ((type.isCopyMinScore() && type.isMaxNegative(psa))
+        || (type.isCopyMaxScore() && type.isMaxPositive(psa))) {
+      return true;
+    }
+    switch (kind) {
+      case MERGE_FIRST_PARENT_UPDATE:
+        return type.isCopyAllScoresOnMergeFirstParentUpdate();
+      case NO_CODE_CHANGE:
+        return type.isCopyAllScoresIfNoCodeChange();
+      case TRIVIAL_REBASE:
+        return type.isCopyAllScoresOnTrivialRebase();
+      case NO_CHANGE:
+        return type.isCopyAllScoresIfNoChange()
+            || type.isCopyAllScoresOnTrivialRebase()
+            || type.isCopyAllScoresOnMergeFirstParentUpdate()
+            || type.isCopyAllScoresIfNoCodeChange();
+      case REWORK:
+      default:
+        return false;
+    }
+  }
+
+  private static PatchSetApproval copy(PatchSetApproval src, PatchSet.Id psId) {
+    if (src.getKey().getParentKey().equals(psId)) {
+      return src;
+    }
+    return new PatchSetApproval(psId, src);
+  }
+}