Line data    Source code

       1             : // Copyright (C) 2022 The Android Open Source Project
       2             : //
       3             : // Licensed under the Apache License, Version 2.0 (the "License");
       4             : // you may not use this file except in compliance with the License.
       5             : // You may obtain a copy of the License at
       6             : //
       7             : // http://www.apache.org/licenses/LICENSE-2.0
       8             : //
       9             : // Unless required by applicable law or agreed to in writing, software
      10             : // distributed under the License is distributed on an "AS IS" BASIS,
      11             : // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
      12             : // See the License for the specific language governing permissions and
      13             : // limitations under the License.
      14             : 
      15             : package com.google.gerrit.server.restapi.change;
      16             : 
      17             : import static com.google.common.base.Preconditions.checkNotNull;
      18             : 
      19             : import com.google.gerrit.extensions.api.changes.ApplyPatchInput;
      20             : import com.google.gerrit.extensions.restapi.BadRequestException;
      21             : import com.google.gerrit.extensions.restapi.RestApiException;
      22             : import java.io.ByteArrayInputStream;
      23             : import java.io.IOException;
      24             : import java.io.InputStream;
      25             : import java.nio.charset.StandardCharsets;
      26             : import org.eclipse.jgit.api.errors.PatchApplyException;
      27             : import org.eclipse.jgit.api.errors.PatchFormatException;
      28             : import org.eclipse.jgit.lib.ObjectId;
      29             : import org.eclipse.jgit.lib.ObjectInserter;
      30             : import org.eclipse.jgit.lib.Repository;
      31             : import org.eclipse.jgit.patch.PatchApplier;
      32             : import org.eclipse.jgit.revwalk.RevCommit;
      33             : import org.eclipse.jgit.revwalk.RevTree;
      34             : 
      35             : /** Utility for applying a patch. */
      36             : public final class ApplyPatchUtil {
      37             : 
      38             :   /**
      39             :    * Applies the given patch on top of the merge tip, using the given object inserter.
      40             :    *
      41             :    * @param repo to apply the patch in
      42             :    * @param oi to operate with
      43             :    * @param input the patch for applying
      44             :    * @param mergeTip the tip to apply the patch on
      45             :    * @return the tree ID with the applied patch
      46             :    * @throws IOException if unable to create the jgit PatchApplier object
      47             :    * @throws RestApiException for any other failure
      48             :    */
      49             :   public static ObjectId applyPatch(
      50             :       Repository repo, ObjectInserter oi, ApplyPatchInput input, RevCommit mergeTip)
      51             :       throws IOException, RestApiException {
      52           2 :     checkNotNull(mergeTip);
      53           2 :     RevTree tip = mergeTip.getTree();
      54           2 :     InputStream patchStream =
      55           2 :         new ByteArrayInputStream(input.patch.getBytes(StandardCharsets.UTF_8));
      56             :     try {
      57           2 :       PatchApplier applier = new PatchApplier(repo, tip, oi);
      58           2 :       PatchApplier.Result applyResult = applier.applyPatch(patchStream);
      59           2 :       return applyResult.getTreeId();
      60           1 :     } catch (PatchFormatException e) {
      61           1 :       throw new BadRequestException("Invalid patch format: " + input.patch, e);
      62           2 :     } catch (PatchApplyException e) {
      63           2 :       throw RestApiException.wrap("Cannot apply patch: " + input.patch, e);
      64             :     }
      65             :   }
      66             : 
      67             :   private ApplyPatchUtil() {}
      68             : }