无法通过Spark连接到Mongo DB [英] Can't connect to Mongo DB via Spark
问题描述
我正在尝试通过Apache Spark主数据库从Mongo DB中读取数据.
I'm trying to read data from Mongo DB through an Apache Spark master.
我为此使用3台机器
- M1-上面有一个Mongo数据库实例
- M2-带有Spark Master，带有Mongo连接器，在其上运行
- M3-具有连接到M2的Spark主控件的python应用程序
应用程序(M3)正在与Spark Master连接，如下所示:
The application(M3) is getting a connection to the spark master like this:
_sparkSession = SparkSession.builder.master(masterPath).appName(appName)\
.config("spark.mongodb.input.uri", "mongodb://10.0.3.150/db1.data.coll")\
.config("spark.mongodb.output.uri", "mongodb://10.0.3.150/db1.data.coll").getOrCreate()
应用程序(M3)试图从数据库中读取数据:
The application(M3) is trying to read data from the DB:
sqlContext = SQLContext(_sparkSession.sparkContext)
df = sqlContext.read.format("com.mongodb.spark.sql.DefaultSource").option("uri","mongodb://user:pass@10.0.3.150/db1.data?readPreference=primaryPreferred").load()
但由于以下异常而失败:
but fails with this exception:
py4j.protocol.Py4JJavaError: An error occurred while calling o56.load.
: java.lang.ClassNotFoundException: Failed to find data source: com.mongodb.spark.sql.DefaultSource. Please find packages at http://spark.apache.org/third-party-projects.html
at org.apache.spark.sql.execution.datasources.DataSource$.lookupDataSource(DataSource.scala:594)
at org.apache.spark.sql.execution.datasources.DataSource.providingClass$lzycompute(DataSource.scala:86)
at org.apache.spark.sql.execution.datasources.DataSource.providingClass(DataSource.scala:86)
at org.apache.spark.sql.execution.datasources.DataSource.resolveRelation(DataSource.scala:325)
at org.apache.spark.sql.DataFrameReader.load(DataFrameReader.scala:152)
at org.apache.spark.sql.DataFrameReader.load(DataFrameReader.scala:125)
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:280)
at py4j.commands.AbstractCommand.invokeMethod(AbstractCommand.java:132)
at py4j.commands.CallCommand.execute(CallCommand.java:79)
at py4j.GatewayConnection.run(GatewayConnection.java:214)
at java.lang.Thread.run(Thread.java:748)
Caused by: java.lang.ClassNotFoundException: com.mongodb.spark.sql.DefaultSource.DefaultSource
at java.net.URLClassLoader.findClass(URLClassLoader.java:381)
at java.lang.ClassLoader.loadClass(ClassLoader.java:424)
at java.lang.ClassLoader.loadClass(ClassLoader.java:357)
at org.apache.spark.sql.execution.datasources.DataSource$$anonfun$25$$anonfun$apply$13.apply(DataSource.scala:579)
at org.apache.spark.sql.execution.datasources.DataSource$$anonfun$25$$anonfun$apply$13.apply(DataSource.scala:579)
at scala.util.Try$.apply(Try.scala:192)
at org.apache.spark.sql.execution.datasources.DataSource$$anonfun$25.apply(DataSource.scala:579)
at org.apache.spark.sql.execution.datasources.DataSource$$anonfun$25.apply(DataSource.scala:579)
at scala.util.Try.orElse(Try.scala:84)
at org.apache.spark.sql.execution.datasources.DataSource$.lookupDataSource(DataSource.scala:579)
... 16 more
推荐答案
Spark无法找到com.mongodb.spark.sql.DefaultSource程序包，因此会出现错误消息.
Spark can't find the com.mongodb.spark.sql.DefaultSource package, hence the error message.
一切都不错，只需要包括Mongo Spark软件包即可:
Everything, else looks good just need to include the Mongo Spark package:
> $SPARK_HOME/bin/pyspark --packages org.mongodb.spark:mongo-spark-connector_2.11:2.2.0
或者确保jar文件位于正确的路径上.
Or ensure that the jar file is on the correct path.
请确保您检查了您的Spark版本所需的Mongo-Spark软件包的版本: https://spark-packages.org/package/mongodb/mongo-spark
Make sure you check the version of the Mongo-Spark package required for your version of Spark: https://spark-packages.org/package/mongodb/mongo-spark
这篇关于无法通过Spark连接到Mongo DB的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！
