首页 > 解决方案 > 使用 spark_read_csv() 从 Rstudio Server 中的 Azure Blob 存储读取 CSV 文件

问题描述

我在 Spark 2.2 上使用 Java 8 HDI 3.6 预配了 Azure HDInsight 群集类型 ML Services (R Server)、操作系统 Linux、ML Services 9.3 版本。

在 Rstudio Server 中,我试图从我的 blob 存储中读取 csv 文件。

Sys.setenv(SPARK_HOME="/usr/hdp/current/spark-client")
Sys.setenv(YARN_CONF_DIR="/etc/hadoop/conf")
Sys.setenv(HADOOP_CONF_DIR="/etc/hadoop/conf")
Sys.setenv(SPARK_CONF_DIR="/etc/spark/conf")

options(rsparkling.sparklingwater.version = "2.2.28")

library(sparklyr)
library(dplyr)
library(h2o)
library(rsparkling)


sc <- spark_connect(master = "yarn-client",
                    version = "2.2.0")

origins <-file.path("wasb://MYDefaultContainer@MyStorageAccount.blob.core.windows.net",
                 "user/RevoShare")

df2 <- spark_read_csv(sc,
                 path = origins,
                 name = 'Nov-MD-Dan',
                 memory = FALSE)```

当我运行它时,我收到以下错误

Error: java.lang.IllegalArgumentException: invalid method csv 
for object 235
at sparklyr.Invoke$.invoke(invoke.scala:122)
at sparklyr.StreamHandler$.handleMethodCall(stream.scala:97)
at sparklyr.StreamHandler$.read(stream.scala:62)
at sparklyr.BackendHandler.channelRead0(handler.scala:52)
at sparklyr.BackendHandler.channelRead0(handler.scala:14)
at 

io.netty.channel.SimpleChannelInboundHandler.channelRead(SimpleCh   annelInboundHandler.java:105)
at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:308)
    at io.netty.channel.AbstractChannelHandlerContext.fireChannelRead(AbstractChannelHandlerContext.java:294)
    at io.netty.handler.codec.MessageToMessageDecoder.channelRead(MessageToMessageDecoder.java:103)
    at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:308)
    at io.netty.channel.AbstractChannelHandlerContext.fireChannelRead(AbstractChannelHandlerContext.java:294)
    at io.netty.handler.codec.ByteToMessageDecoder.channelRead(ByteToMessageDecoder.java:244)
    at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:308)
    at io.netty.channel.AbstractChannelHandlerContext.fireChannelRead(AbstractChannelHandlerContext.java:294)
    at io.netty.channel.DefaultChannelPipeline.fireChannelRead(DefaultChannelPipeline.java:846)
    at io.netty.channel.nio.AbstractNioByteChannel$NioByteUnsafe.read(AbstractNioByteChannel.java:131)
    at io.netty.channel.nio.NioEventLoop.processSelectedKey(NioEventLoop.java:511)
    at io.netty.channel.nio.NioEventLoop.processSelectedKeysOptimized(NioEventLoop.java:468)
    at io.netty.channel.nio.NioEventLoop.processSelectedKeys(NioEventLoop.java:382)
    at io.netty.channel.nio.NioEventLoop.run(NioEventLoop.java:354)
    at io.netty.util.concurrent.SingleThreadEventExecutor$2.run(SingleThreadEventExecutor.java:111)
    at io.netty.util.concurrent.DefaultThreadFactory$DefaultRunnableDecorator.run(DefaultThreadFactory.java:137)
    at java.lang.Thread.run(Thread.java:748)

任何帮助都是极好的!

标签: apache-sparkrstudiosparklyrrstudio-server

解决方案


路径origins应指向 CSV 文件或 CSV 目录。你确定它origins指向一个文件目录还是一个文件?对于每个 HDFS 用户,通常至少还有一个目录/user/RevoShare/,即/user/RevoShare/sshuser/.

这是一个可能有帮助的例子:

sample_file <- file.path("/example/data/", "yellowthings.txt")

library(sparklyr)
library(dplyr)
cc <- rxSparkConnect(interop = "sparklyr")
sc <- rxGetSparklyrConnection(cc)

fruits <- spark_read_csv(sc, path = sample_file, name = "fruits", header = FALSE)

您可以使用RxHadoopListFiles("/example/data/")或使用hdfs dfs -ls /example/data来检查 HDFS / Blob 上的目录。


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