elasticsearch导入失败

[silly01]

调用这个接口报错，http://localhost:8080/esProduct/importAll，什么原因呢

{
"timestamp": "2019-10-01T02:40:07.016+0000",
"status": 500,
"error": "Internal Server Error",
"message": "Bulk indexing has failures. Use ElasticsearchException.getFailedDocuments() for detailed messages [{33=RemoteTransportException[[NzqGfTB][172.17.0.2:9300][indices:data/write/bulk[s][p]]]; nested: TranslogException[Failed to write operation [NoOp{seqNo=0, primaryTerm=4, reason='null'}]]; nested: NullPointerException;, 34=RemoteTransportException[[NzqGfTB][172.17.0.2:9300][indices:data/write/bulk[s][p]]]; nested: TranslogException[Failed to write operation [NoOp{seqNo=0, primaryTerm=4, reason='null'}]]; nested: NullPointerException;, 35=RemoteTransportException[[NzqGfTB][172.17.0.2:9300][indices:data/write/bulk[s][p]]]; nested: TranslogException[Failed to write operation [NoOp{seqNo=0, primaryTerm=4, reason='null'}]]; nested: NullPointerException;, 36=RemoteTransportException[[NzqGfTB][172.17.0.2:9300][indices:data/write/bulk[s][p]]]; nested: TranslogException[Failed to write operation [NoOp{seqNo=0, primaryTerm=4, reason='null'}]]; nested: NullPointerException;, 26=RemoteTransportException[[NzqGfTB][172.17.0.2:9300][indices:data/write/bulk[s][p]]]; nested: TranslogException[Failed to write operation [NoOp{seqNo=0, primaryTerm=4, reason='null'}]]; nested: NullPointerException;, 27=RemoteTransportException[[NzqGfTB][172.17.0.2:9300][indices:data/write/bulk[s][p]]]; nested: TranslogException[Failed to write operation [NoOp{seqNo=0, primaryTerm=4, reason='null'}]]; nested: NullPointerException;, 28=RemoteTransportException[[NzqGfTB][172.17.0.2:9300][indices:data/write/bulk[s][p]]]; nested: TranslogException[Failed to write operation [NoOp{seqNo=0, primaryTerm=4, reason='null'}]]; nested: NullPointerException;, 29=RemoteTransportException[[NzqGfTB][172.17.0.2:9300][indices:data/write/bulk[s][p]]]; nested: TranslogException[Failed to write operation [NoOp{seqNo=0, primaryTerm=4, reason='null'}]]; nested: NullPointerException;, 30=RemoteTransportException[[NzqGfTB][172.17.0.2:9300][indices:data/write/bulk[s][p]]]; nested: TranslogException[Failed to write operation [NoOp{seqNo=0, primaryTerm=4, reason='null'}]]; nested: NullPointerException;, 31=RemoteTransportException[[NzqGfTB][172.17.0.2:9300][indices:data/write/bulk[s][p]]]; nested: TranslogException[Failed to write operation [NoOp{seqNo=0, primaryTerm=4, reason='null'}]]; nested: NullPointerException;, 32=RemoteTransportException[[NzqGfTB][172.17.0.2:9300][indices:data/write/bulk[s][p]]]; nested: TranslogException[Failed to write operation [NoOp{seqNo=0, primaryTerm=4, reason='null'}]]; nested: NullPointerException;}]",
"path": "/esProduct/importAll"
}