private void createDownstreamMerges()

in src/main/java/com/googlesource/gerrit/plugins/automerger/DownstreamCreator.java [353:432]
73 lines of code
10 McCabe index (conditional complexity)

  private void createDownstreamMerges(MultipleDownstreamMergeInput mdsMergeInput)
      throws RestApiException, FailedMergeException, ConfigInvalidException,
          InvalidQueryParameterException, StorageException {
    try (ManualRequestContext ctx = oneOffRequestContext.openAs(config.getContextUserId())) {
      // Map from branch to error message
      Map<String, String> failedMergeBranchMap = new TreeMap<>();

      List<Integer> existingDownstream;
      for (String downstreamBranch : mdsMergeInput.dsBranchMap.keySet()) {
        // If there are existing downstream merges, update them
        // Otherwise, create them.
        boolean createDownstreams = true;
        if (mdsMergeInput.obsoleteRevision != null) {
          existingDownstream =
              getExistingMergesOnBranch(
                  mdsMergeInput.obsoleteRevision, mdsMergeInput.topic, downstreamBranch);
          if (!existingDownstream.isEmpty()) {
            log.debug(
                "Attempting to update downstream merge of {} on branch {}",
                mdsMergeInput.currentRevision,
                downstreamBranch);
            // existingDownstream should almost always be of length one, but
            // it's possible to construct it so that it's not
            for (Integer dsChangeNumber : existingDownstream) {
              try {
                updateDownstreamMerge(
                    mdsMergeInput.currentRevision,
                    mdsMergeInput.subject,
                    dsChangeNumber,
                    mdsMergeInput.dsBranchMap.get(downstreamBranch),
                    mdsMergeInput.changeNumber,
                    downstreamBranch);
                createDownstreams = false;
              } catch (MergeConflictException e) {
                failedMergeBranchMap.put(downstreamBranch, e.getMessage());
                log.debug(
                    "Abandoning existing, obsolete {} due to merge conflict.", dsChangeNumber);
                abandonChange(dsChangeNumber);
              }
            }
          }
        }
        if (createDownstreams) {
          log.debug(
              "Attempting to create downstream merge of {} on branch {}",
              mdsMergeInput.currentRevision,
              downstreamBranch);
          SingleDownstreamMergeInput sdsMergeInput = new SingleDownstreamMergeInput();
          sdsMergeInput.currentRevision = mdsMergeInput.currentRevision;
          sdsMergeInput.changeNumber = mdsMergeInput.changeNumber;
          sdsMergeInput.project = mdsMergeInput.project;
          sdsMergeInput.topic = mdsMergeInput.topic;
          sdsMergeInput.subject = mdsMergeInput.subject;
          sdsMergeInput.downstreamBranch = downstreamBranch;
          sdsMergeInput.doMerge = mdsMergeInput.dsBranchMap.get(downstreamBranch);
          try {
            createSingleDownstreamMerge(sdsMergeInput);
          } catch (MergeConflictException e) {
            failedMergeBranchMap.put(downstreamBranch, e.getMessage());
          }
        }
      }

      if (!failedMergeBranchMap.isEmpty()) {
        String conflictMessage = config.getConflictMessage();
        if (mdsMergeInput.project.equals(config.getManifestProject())) {
          conflictMessage = config.getManifestConflictMessage();
        }
        throw new FailedMergeException(
            failedMergeBranchMap,
            mdsMergeInput.currentRevision,
            config.getHostName(),
            mdsMergeInput.project,
            mdsMergeInput.changeNumber,
            mdsMergeInput.patchsetNumber,
            conflictMessage,
            mdsMergeInput.topic);
      }
    }
  }