feat: add object retention feature (#2277)

* feat: add object retention feature

* 🦉 Updates from OwlBot post-processor

See https://github.com/googleapis/repo-automation-bots/blob/main/packages/owl-bot/README.md

* address review comments

* 🦉 Updates from OwlBot post-processor

See https://github.com/googleapis/repo-automation-bots/blob/main/packages/owl-bot/README.md

* Add a workaround to avoid a testbench failure

* chore: some fixes from pairing with jesse

* chore: put a `!` :don't program while sleepy:

* chore: mvn-fmt

* add a way to avoid using the objectRetentionField in bucket tests

* add retention to blobfield tests

* clirr and fmt

* add todos

* fmt

---------

Co-authored-by: Owl Bot <gcf-owl-bot[bot]@users.noreply.github.com>
Co-authored-by: BenWhitehead <BenWhitehead@users.noreply.github.com>

google-cloud-storage/clirr-ignored-differences.xml

@@ -15,6 +15,12 @@
     <method>* writeAndClose(*)</method>
   </difference>
 
+  <difference>
+    <differenceType>7013</differenceType>
+    <className>com/google/cloud/storage/BlobInfo$Builder</className>
+    <method>com.google.cloud.storage.BlobInfo$Builder setRetention(com.google.cloud.storage.BlobInfo$Retention)</method>
+  </difference>
+
   <!-- @BetaApi members -->
   <difference>
     <differenceType>7009</differenceType>

google-cloud-storage/src/main/java/com/google/cloud/storage/Blob.java

@@ -526,6 +526,12 @@ Builder setRetentionExpirationTimeOffsetDateTime(OffsetDateTime retentionExpirat
       return this;
     }
 
+    @Override
+    public Builder setRetention(Retention retention) {
+      infoBuilder.setRetention(retention);
+      return this;
+    }
+
     @Override
     public Blob build() {
       return new Blob(storage, infoBuilder);

google-cloud-storage/src/main/java/com/google/cloud/storage/BlobInfo.java

@@ -22,7 +22,10 @@
 import static com.google.common.base.Preconditions.checkNotNull;
 
 import com.google.api.client.util.Data;
+import com.google.api.core.ApiFunction;
 import com.google.api.core.BetaApi;
+import com.google.cloud.StringEnumType;
+import com.google.cloud.StringEnumValue;
 import com.google.cloud.storage.Storage.BlobField;
 import com.google.cloud.storage.TransportCompatibility.Transport;
 import com.google.cloud.storage.UnifiedOpts.NamedField;
@@ -104,6 +107,7 @@ public class BlobInfo implements Serializable {
   private final Boolean eventBasedHold;
   private final Boolean temporaryHold;
   private final OffsetDateTime retentionExpirationTime;
+  private final Retention retention;
   private final transient ImmutableSet<NamedField> modifiedFields;
 
   /** This class is meant for internal use only. Users are discouraged from using this class. */
@@ -168,6 +172,119 @@ public final boolean equals(Object o) {
     }
   }
 
+  /**
+   * Defines a blob's Retention policy. Can only be used on objects in a retention-enabled bucket.
+   */
+  public static final class Retention implements Serializable {
+
+    private static final long serialVersionUID = 5046718464542688444L;
+
+    private Mode mode;
+
+    private OffsetDateTime retainUntilTime;
+
+    /** Returns the retention policy's Mode. Can be Locked or Unlocked. */
+    public Mode getMode() {
+      return mode;
+    }
+
+    /** Returns what time this object will be retained until, if the mode is Locked. */
+    public OffsetDateTime getRetainUntilTime() {
+      return retainUntilTime;
+    }
+
+    @Override
+    public boolean equals(Object o) {
+      if (this == o) {
+        return true;
+      }
+      if (!(o instanceof Retention)) {
+        return false;
+      }
+      Retention that = (Retention) o;
+      return Objects.equals(mode, that.mode)
+          && Objects.equals(retainUntilTime, that.retainUntilTime);
+    }
+
+    @Override
+    public int hashCode() {
+      return Objects.hash(mode, retainUntilTime);
+    }
+
+    @Override
+    public String toString() {
+      return MoreObjects.toStringHelper(this)
+          .add("mode", mode)
+          .add("retainUntilTime", retainUntilTime)
+          .toString();
+    }
+
+    public static Builder newBuilder() {
+      return new Builder();
+    }
+
+    public Builder toBuilder() {
+      return new Builder().setMode(this.mode).setRetainUntilTime(this.retainUntilTime);
+    }
+
+    private Retention() {}
+
+    public Retention(Builder builder) {
+      this.mode = builder.mode;
+      this.retainUntilTime = builder.retainUntilTime;
+    }
+
+    public static final class Builder {
+      private Mode mode;
+      private OffsetDateTime retainUntilTime;
+
+      /** Sets the retention policy's Mode. Can be Locked or Unlocked. */
+      public Builder setMode(Mode mode) {
+        this.mode = mode;
+        return this;
+      }
+
+      /** Sets what time this object will be retained until, if the mode is Locked. */
+      public Builder setRetainUntilTime(OffsetDateTime retainUntilTime) {
+        this.retainUntilTime = retainUntilTime;
+        return this;
+      }
+
+      public Retention build() {
+        return new Retention(this);
+      }
+    }
+
+    public static final class Mode extends StringEnumValue {
+      private static final long serialVersionUID = 1973143582659557184L;
+
+      private Mode(String constant) {
+        super(constant);
+      }
+
+      private static final ApiFunction<String, Mode> CONSTRUCTOR = Mode::new;
+
+      private static final StringEnumType<Mode> type =
+          new StringEnumType<>(Mode.class, CONSTRUCTOR);
+
+      public static final Mode UNLOCKED = type.createAndRegister("Unlocked");
+
+      public static final Mode LOCKED = type.createAndRegister("Locked");
+
+      public static Mode valueOfStrict(String constant) {
+        return type.valueOfStrict(constant);
+      }
+
+      public static Mode valueOf(String constant) {
+        return type.valueOf(constant);
+      }
+
+      public static Mode[] values() {
+        return type.values();
+      }
+    }
+  }
+
   /** Builder for {@code BlobInfo}. */
   public abstract static class Builder {
 
@@ -408,6 +525,8 @@ Builder setRetentionExpirationTimeOffsetDateTime(OffsetDateTime retentionExpirat
       return setRetentionExpirationTime(millisOffsetDateTimeCodec.decode(retentionExpirationTime));
     }
 
+    public abstract Builder setRetention(Retention retention);
+
     /** Creates a {@code BlobInfo} object. */
     public abstract BlobInfo build();
 
@@ -506,6 +625,7 @@ static final class BuilderImpl extends Builder {
     private Boolean eventBasedHold;
     private Boolean temporaryHold;
     private OffsetDateTime retentionExpirationTime;
+    private Retention retention;
     private final ImmutableSet.Builder<NamedField> modifiedFields = ImmutableSet.builder();
 
     BuilderImpl(BlobId blobId) {
@@ -543,6 +663,7 @@ static final class BuilderImpl extends Builder {
       eventBasedHold = blobInfo.eventBasedHold;
       temporaryHold = blobInfo.temporaryHold;
       retentionExpirationTime = blobInfo.retentionExpirationTime;
+      retention = blobInfo.retention;
     }
 
     @Override
@@ -916,6 +1037,14 @@ Builder setRetentionExpirationTimeOffsetDateTime(OffsetDateTime retentionExpirat
       return this;
     }
 
+    @Override
+    public Builder setRetention(Retention retention) {
+      // todo: b/308194853
+      modifiedFields.add(BlobField.RETENTION);
+      this.retention = retention;
+      return this;
+    }
+
     @Override
     public BlobInfo build() {
       checkNotNull(blobId);
@@ -1139,6 +1268,7 @@ Builder clearRetentionExpirationTime() {
     eventBasedHold = builder.eventBasedHold;
     temporaryHold = builder.temporaryHold;
     retentionExpirationTime = builder.retentionExpirationTime;
+    retention = builder.retention;
     modifiedFields = builder.modifiedFields.build();
   }
 
@@ -1532,6 +1662,11 @@ public OffsetDateTime getRetentionExpirationTimeOffsetDateTime() {
     return retentionExpirationTime;
   }
 
+  /** Returns the object's Retention policy. */
+  public Retention getRetention() {
+    return retention;
+  }
+
   /** Returns a builder for the current blob. */
   public Builder toBuilder() {
     return new BuilderImpl(this);
@@ -1581,6 +1716,7 @@ public int hashCode() {
         kmsKeyName,
         eventBasedHold,
         temporaryHold,
+        retention,
         retentionExpirationTime);
   }
 
@@ -1622,7 +1758,8 @@ public boolean equals(Object o) {
         && Objects.equals(kmsKeyName, blobInfo.kmsKeyName)
         && Objects.equals(eventBasedHold, blobInfo.eventBasedHold)
         && Objects.equals(temporaryHold, blobInfo.temporaryHold)
-        && Objects.equals(retentionExpirationTime, blobInfo.retentionExpirationTime);
+        && Objects.equals(retentionExpirationTime, blobInfo.retentionExpirationTime)
+        && Objects.equals(retention, blobInfo.retention);
   }
 
   ImmutableSet<NamedField> getModifiedFields() {

google-cloud-storage/src/main/java/com/google/cloud/storage/Bucket.java

@@ -272,6 +272,16 @@ public static BlobTargetOption userProject(@NonNull String userProject) {
       return new BlobTargetOption(UnifiedOpts.userProject(userProject));
     }
 
+    /**
+     * Returns an option for overriding an Unlocked Retention policy. This must be set to true in
+     * order to change a policy from Unlocked to Locked, to set it to null, or to reduce its
+     * retainUntilTime attribute.
+     */
+    @TransportCompatibility({Transport.HTTP})
+    public static BlobTargetOption overrideUnlockedRetention(boolean overrideUnlockedRetention) {
+      return new BlobTargetOption(UnifiedOpts.overrideUnlockedRetention(overrideUnlockedRetention));
+    }
+
     /**
      * Deduplicate any options which are the same parameter. The value which comes last in {@code
      * os} will be the value included in the return.
@@ -732,6 +742,12 @@ public Builder setCustomPlacementConfig(CustomPlacementConfig customPlacementCon
       return this;
     }
 
+    @Override
+    Builder setObjectRetention(ObjectRetention objectRetention) {
+      infoBuilder.setObjectRetention(objectRetention);
+      return this;
+    }
+
     @Override
     public Bucket build() {
       return new Bucket(storage, infoBuilder);