使用 PySpark 和 Kafka 的结构化流处理，Py4JJavaError: An error occurred while calling o70.awaitTermination

Question

我尝试使用 Spark 从 Kafka 消费，更具体地说是 PySpark 和 Structured Streaming。

import os
import time
import time

from ast import literal_eval
from pyspark.sql.types import *
from pyspark.sql.functions import from_json, col, struct, explode
from pyspark.sql import SparkSession
os.environ['PYSPARK_SUBMIT_ARGS'] = '--packages org.apache.spark:spark-sql-kafka-0-10_2.11:2.3.0 pyspark-shell'

spark = SparkSession \
    .builder \
    .appName("Structured Streaming") \
    .getOrCreate()

    requests = spark \
  .readStream \
  .format("kafka") \
  .option("kafka.bootstrap.servers", "ip-ec2:9092") \
  .option("subscribe", "ssp.requests") \
  .option("startingOffsets", "earliest") \
  .load()

requests.printSchema()

# root  |-- key: binary (nullable = true)  |-- value: binary (nullable =
# true)  |-- topic: string (nullable = true)  |-- partition: integer
# (nullable = true)  |-- offset: long (nullable = true)  |-- timestamp:
# timestamp (nullable = true)  |-- timestampType: integer (nullable =
# true)

当我运行下一行代码时

rawQuery = requests \
        .selectExpr("topic", "CAST(key AS STRING)", "CAST(value AS STRING)") \
        .writeStream.trigger(processingTime="5 seconds") \
        .format("parquet") \
        .option("checkpointLocation", "/home/user/folder/applicationHistory") \
        .option("path", "/home/user/folder") \
        .start()
rawQuery.awaitTermination()    

Py4JJavaError Traceback（最近调用 最后）/opt/conda/lib/python3.6/site-packages/pyspark/sql/utils.py 在 装饰(*a, **kw) 62 尝试： ---> 63 返回 f(*a, **kw) 64 除了 py4j.protocol.Py4JJavaError as e:

/opt/conda/lib/python3.6/site-packages/py4j/protocol.py 在 get_return_value(answer, gateway_client, target_id, name) 319 “调用 {0}{1}{2} 时出错。\n”。 --> 320 格式(target_id, ".", name), value) 321 其他：

Py4JJavaError：调用 o70.awaitTermination 时出错。 ： org.apache.spark.sql.streaming.StreamingQueryException：作业中止。 === 流式查询 === 标识符：[id = c2b48840-5ba4-416e-a192-dcae94007856, runId = 4afcca20-00cd-4187-a70b-1b742f1f5c0d] 当前提交的偏移量：{} 当前可用的偏移量：{KafkaSource[Subscribe[ssp.requests]]：

我无法理解这个错误的原因

Py4JJavaError: 调用 o70.awaitTermination 时出错

Answer 1

我刚刚将 rawQuery.awaitTermination() 行替换为

print(rawQuery.status)
time.sleep(60)
print(rawQuery.status)
rawQuery.stop()

它有效。