code: @Override
    public Schema getSchema() {
      if (this.workUnit.contains(ConfigurationKeys.SOURCE_SCHEMA)) {
        return new Schema.Parser().parse(this.workUnit.getProp(ConfigurationKeys.SOURCE_SCHEMA));
      }
  
      AvroFsHelper hfsHelper = (AvroFsHelper) this.fsHelper;
      if (this.filesToPull.isEmpty()) {
        return null;
      }
      try {
        return hfsHelper.getAvroSchema(this.filesToPull.get(0));
      } catch (FileBasedHelperException e) {
        Throwables.propagate(e);
        return null;
      }
    }
docs: Assumption is that all files in the input directory have the same schema