[metastore] Sample fetch breaks the page when it fails with error 1

http://127.0.0.1:8000/notebook/api/sample/default/customers

{"status": 1, "message": "Bad status for request TFetchResultsReq(fetchType=0, operationHandle=TOperationHandle(hasResultSet=True, modifiedRowCount=None, operationType=0, operationId=THandleIdentifier(secret='\\xe6a\\xa5\\xb2\\xd5\"GW\\x9e\\xe3\\xee\\xceMSc\\x05', guid='\\xb1\\x80yf\\x949@\\xc8\\x89g\\xfd\\xf2\\x07\\xd1\\xf4\\xbd')), orientation=0, maxRows=100):\nTFetchResultsResp(status=TStatus(errorCode=0, errorMessage='java.io.IOException: java.lang.RuntimeException: hdfs://localhost:8020/user/hive/warehouse/customers/customers.json is not a Parquet file. expected magic number at tail [80, 65, 82, 49] but found [125, 93, 125, 10]', sqlState=None, infoMessages=['*org.apache.hive.service.cli.HiveSQLException:java.io.IOException: java.lang.RuntimeException: hdfs://localhost:8020/user/hive/warehouse/customers/customers.json is not a Parquet file. expected magic number at tail [80, 65, 82, 49] but found [125, 93, 125, 10]:25:24', 'org.apache.hive.service.cli.operation.SQLOperation:getNextRowSet:SQLOperation.java:366', 'org.apache.hive.service.cli.operation.OperationManager:getOperationNextRowSet:OperationManager.java:275', 'org.apache.hive.service.cli.session.HiveSessionImpl:fetchResults:HiveSessionImpl.java:751', 'sun.reflect.GeneratedMethodAccessor50:invoke::-1', 'sun.reflect.DelegatingMethodAccessorImpl:invoke:DelegatingMethodAccessorImpl.java:43', 'java.lang.reflect.Method:invoke:Method.java:606', 'org.apache.hive.service.cli.session.HiveSessionProxy:invoke:HiveSessionProxy.java:78', 'org.apache.hive.service.cli.session.HiveSessionProxy:access$000:HiveSessionProxy.java:36', 'org.apache.hive.service.cli.session.HiveSessionProxy$1:run:HiveSessionProxy.java:63', 'java.security.AccessController:doPrivileged:AccessController.java:-2', 'javax.security.auth.Subject:doAs:Subject.java:415', 'org.apache.hadoop.security.UserGroupInformation:doAs:UserGroupInformation.java:1693', 'org.apache.hive.service.cli.session.HiveSessionProxy:invoke:HiveSessionProxy.java:59', 'com.sun.proxy.$Proxy19:fetchResults::-1', 'org.apache.hive.service.cli.CLIService:fetchResults:CLIService.java:438', 'org.apache.hive.service.cli.thrift.ThriftCLIService:FetchResults:ThriftCLIService.java:689', 'org.apache.hive.service.cli.thrift.TCLIService$Processor$FetchResults:getResult:TCLIService.java:1553', 'org.apache.hive.service.cli.thrift.TCLIService$Processor$FetchResults:getResult:TCLIService.java:1538', 'org.apache.thrift.ProcessFunction:process:ProcessFunction.java:39', 'org.apache.thrift.TBaseProcessor:process:TBaseProcessor.java:39', 'org.apache.hive.service.auth.TSetIpAddressProcessor:process:TSetIpAddressProcessor.java:56', 'org.apache.thrift.server.TThreadPoolServer$WorkerProcess:run:TThreadPoolServer.java:286', 'java.util.concurrent.ThreadPoolExecutor:runWorker:ThreadPoolExecutor.java:1145', 'java.util.concurrent.ThreadPoolExecutor$Worker:run:ThreadPoolExecutor.java:615', 'java.lang.Thread:run:Thread.java:745', '*java.io.IOException:java.lang.RuntimeException: hdfs://localhost:8020/user/hive/warehouse/customers/customers.json is not a Parquet file. expected magic number at tail [80, 65, 82, 49] but found [125, 93, 125, 10]:29:4', 'org.apache.hadoop.hive.ql.exec.FetchOperator:getNextRow:FetchOperator.java:508', 'org.apache.hadoop.hive.ql.exec.FetchOperator:pushRow:FetchOperator.java:415', 'org.apache.hadoop.hive.ql.exec.FetchTask:fetch:FetchTask.java:138', 'org.apache.hadoop.hive.ql.Driver:getResults:Driver.java:1798', 'org.apache.hive.service.cli.operation.SQLOperation:getNextRowSet:SQLOperation.java:361', '*java.lang.RuntimeException:hdfs://localhost:8020/user/hive/warehouse/customers/customers.json is not a Parquet file. expected magic number at tail [80, 65, 82, 49] but found [125, 93, 125, 10]:38:9', 'parquet.hadoop.ParquetFileReader:readFooter:ParquetFileReader.java:423', 'parquet.hadoop.ParquetFileReader:readFooter:ParquetFileReader.java:386', 'parquet.hadoop.ParquetFileReader:readFooter:ParquetFileReader.java:372', 'org.apache.hadoop.hive.ql.io.parquet.read.ParquetRecordReaderWrapper:getSplit:ParquetRecordReaderWrapper.java:252', 'org.apache.hadoop.hive.ql.io.parquet.read.ParquetRecordReaderWrapper:<init>:ParquetRecordReaderWrapper.java:95', 'org.apache.hadoop.hive.ql.io.parquet.read.ParquetRecordReaderWrapper:<init>:ParquetRecordReaderWrapper.java:81', 'org.apache.hadoop.hive.ql.io.parquet.MapredParquetInputFormat:getRecordReader:MapredParquetInputFormat.java:72', 'org.apache.hadoop.hive.ql.exec.FetchOperator$FetchInputFormatSplit:getRecordReader:FetchOperator.java:674', 'org.apache.hadoop.hive.ql.exec.FetchOperator:getRecordReader:FetchOperator.java:324', 'org.apache.hadoop.hive.ql.exec.FetchOperator:getNextRow:FetchOperator.java:446'], statusCode=3), results=None, hasMoreRows=None)"}