我想在S3上写一个csv
文件,该文件应由dataframe
组成。我尝试像普通api中一样将数据帧保存到csv,但是不幸的是,稍后在将文件上传到S3时无法访问。
然后,我想到了将文件直接保存到S3的功能,这是我能够正常进行的操作,但不能在此处进行。
我正在使用AWS EMR的Spark集群。我尝试了多种格式,每种格式最终都会产生结果。
解决了一件事情,将文件保存到HDFS,然后读取它。但是,我无法访问HDFS路径,因此无法上传文件。
>>> df.write.parquet("s3a://demo-atlan-lake/shri/test.parquet",mode="overwrite")
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
File "/usr/lib/spark/python/pyspark/sql/readwriter.py", line 839, in parquet
self._jwrite.parquet(path)
File "/usr/lib/spark/python/lib/py4j-0.10.7-src.zip/py4j/java_gateway.py", line 1257, in __call__
File "/usr/lib/spark/python/pyspark/sql/utils.py", line 63, in deco
return f(*a, **kw)
File "/usr/lib/spark/python/lib/py4j-0.10.7-src.zip/py4j/protocol.py", line 328, in get_return_value
py4j.protocol.Py4JJavaError: An error occurred while calling o101.parquet.
: java.lang.RuntimeException: java.lang.ClassNotFoundException: Class org.apache.hadoop.fs.s3a.S3AFileSystem not found
at org.apache.hadoop.conf.Configuration.getClass(Configuration.java:2369)
at org.apache.hadoop.fs.FileSystem.getFileSystemClass(FileSystem.java:2840)
at org.apache.hadoop.fs.FileSystem.createFileSystem(FileSystem.java:2857)
at org.apache.hadoop.fs.FileSystem.access$200(FileSystem.java:99)
at org.apache.hadoop.fs.FileSystem$Cache.getInternal(FileSystem.java:2896)
at org.apache.hadoop.fs.FileSystem$Cache.get(FileSystem.java:2878)
at org.apache.hadoop.fs.FileSystem.get(FileSystem.java:392)
at org.apache.hadoop.fs.Path.getFileSystem(Path.java:356)
at org.apache.spark.sql.execution.datasources.DataSource.planForWritingFileFormat(DataSource.scala:424)
at org.apache.spark.sql.execution.datasources.DataSource.planForWriting(DataSource.scala:524)
at org.apache.spark.sql.DataFrameWriter.saveToV1Source(DataFrameWriter.scala:290)
at org.apache.spark.sql.DataFrameWriter.save(DataFrameWriter.scala:271)
at org.apache.spark.sql.DataFrameWriter.save(DataFrameWriter.scala:229)
at org.apache.spark.sql.DataFrameWriter.parquet(DataFrameWriter.scala:566)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:498)
at py4j.reflection.MethodInvoker.invoke(MethodInvoker.java:244)
at py4j.reflection.ReflectionEngine.invoke(ReflectionEngine.java:357)
at py4j.Gateway.invoke(Gateway.java:282)
at py4j.commands.AbstractCommand.invokeMethod(AbstractCommand.java:132)
at py4j.commands.CallCommand.execute(CallCommand.java:79)
at py4j.GatewayConnection.run(GatewayConnection.java:238)
at java.lang.Thread.run(Thread.java:748)
Caused by: java.lang.ClassNotFoundException: Class org.apache.hadoop.fs.s3a.S3AFileSystem not found
at org.apache.hadoop.conf.Configuration.getClassByName(Configuration.java:2273)
at org.apache.hadoop.conf.Configuration.getClass(Configuration.java:2367)
... 24 more
我希望csv文件或任何其他文件上载到对象存储。
最佳答案
不久前,我遇到了同样的问题。
将类似python相关的行添加到spark会话,并添加s3-python depedency。
sparkSession.sparkContext.hadoopConfiguration.set("fs.s3n.impl", "org.apache.hadoop.fs.s3native.NativeS3FileSystem")
sparkSession.sparkContext.hadoopConfiguration.set("fs.s3a.access.key", "access key")
sparkSession.sparkContext.hadoopConfiguration.set("fs.s3a.secret.key", "secret key")