我正在通过 PySpark 探索 Spark Streaming,当我尝试将transform函数与take.
我可以成功地使用sortBy过DStream孔transform和pprint结果。
author_counts_sorted_dstream = author_counts_dstream.transform\
(lambda foo:foo\
.sortBy(lambda x:x[0].lower())\
.sortBy(lambda x:x[1],ascending=False))
author_counts_sorted_dstream.pprint()
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但是如果我使用take以下相同的模式并尝试pprint它:
top_five = author_counts_sorted_dstream.transform\
(lambda rdd:rdd.take(5))
top_five.pprint()
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工作失败
Run Code Online (Sandbox Code Playgroud)Py4JJavaError: An error occurred while calling o25.awaitTermination. : org.apache.spark.SparkException: An exception was raised by Python: Traceback (most recent call last): File "/usr/local/spark/python/pyspark/streaming/util.py", line 67, in call return r._jrdd AttributeError: 'list' object has no attribute '_jrdd'
您可以在此处查看笔记本中的完整代码和输出。
我究竟做错了什么?