PySpark Example Code¶
Development Description¶
The CloudTable HBase and MRS HBase can be connected to DLI as data sources.
Prerequisites
A datasource connection has been created on the DLI management console.
Note
Hard-coded or plaintext passwords pose significant security risks. To ensure security, encrypt your passwords, store them in configuration files or environment variables, and decrypt them when needed.
Code implementation
Import dependency packages.
from __future__ import print_function from pyspark.sql.types import StructType, StructField, IntegerType, StringType, BooleanType, ShortType, LongType, FloatType, DoubleType from pyspark.sql import SparkSession
Create a session.
sparkSession = SparkSession.builder.appName("datasource-hbase").getOrCreate()
Connecting to data sources through SQL APIs
Create a table to connect to an HBase data source.
The sample code is applicable, if Kerberos authentication is disabled for the interconnected HBase cluster:
sparkSession.sql( "CREATE TABLE testhbase(id STRING, location STRING, city STRING) using hbase OPTIONS (\ 'ZKHost' = '192.168.0.189:2181',\ 'TableName' = 'hbtest',\ 'RowKey' = 'id:5',\ 'Cols' = 'location:info.location,city:detail.city')")
The sample code is applicable, if Kerberos authentication is enabled for the interconnected HBase cluster:
sparkSession.sql( "CREATE TABLE testhbase(id STRING, location STRING, city STRING) using hbase OPTIONS (\ 'ZKHost' = '192.168.0.189:2181',\ 'TableName' = 'hbtest',\ 'RowKey' = 'id:5',\ 'Cols' = 'location:info.location,city:detail.city',\ 'krb5conf' = './krb5.conf',\ 'keytab'='./user.keytab',\ 'principal' ='krbtest')")
If Kerberos authentication is enabled, you need to set three more parameters, as listed in Table 1.
Table 1 Description¶ Parameter and Value
Description
'krb5conf' = './krb5.conf'
Path of the krb5.conf file.
'keytab'='./user.keytab'
Path of the keytab file.
'principal' ='krbtest'
Authentication username.
For details about how to obtain the krb5.conf and keytab files, see Completing Configurations for Enabling Kerberos Authentication.
Note
For details about parameters in the table, see Table 1.
Import data to HBase.
sparkSession.sql("insert into testhbase values('95274','abc','Jinan')")
Read data from HBase.
sparkSession.sql("select * from testhbase").show()
Connecting to data sources through DataFrame APIs
Create a table to connect to an HBase data source.
sparkSession.sql(\ "CREATE TABLE test_hbase(id STRING, location STRING, city STRING, booleanf BOOLEAN, shortf SHORT, intf INT, longf LONG, floatf FLOAT, doublef DOUBLE) using hbase OPTIONS (\ 'ZKHost' = 'cloudtable-cf82-zk3-pa6HnHpf.cloudtable.com:2181,\ cloudtable-cf82-zk2-weBkIrjI.cloudtable.com:2181,\ cloudtable-cf82-zk1-WY09px9l.cloudtable.com:2181',\ 'TableName' = 'table_DupRowkey1',\ 'RowKey' = 'id:5,location:6,city:7',\ 'Cols' = 'booleanf:CF1.booleanf, shortf:CF1.shortf, intf:CF1.intf, \ longf:CF1.longf, floatf:CF1.floatf, doublef:CF1.doublef')")
Note
For details about the ZKHost, RowKey, and Cols parameters, see Table 1.
TableName: Name of a table in the CloudTable file. If no table name exists, the system automatically creates one.
Construct a schema.
schema = StructType([StructField("id", StringType()),\ StructField("location", StringType()),\ StructField("city", StringType()),\ StructField("booleanf", BooleanType()),\ StructField("shortf", ShortType()),\ StructField("intf", IntegerType()),\ StructField("longf", LongType()),\ StructField("floatf", FloatType()),\ StructField("doublef", DoubleType())])
Set data.
dataList = sparkSession.sparkContext.parallelize([("11111", "aaa", "aaa", False, 4, 3, 23, 2.3, 2.34)])
Create a DataFrame.
dataFrame = sparkSession.createDataFrame(dataList, schema)
Import data to HBase.
dataFrame.write.insertInto("test_hbase")
Read data from HBase.
// Set cross-source connection parameters TableName = "table_DupRowkey1" RowKey = "id:5,location:6,city:7" Cols = "booleanf:CF1.booleanf,shortf:CF1.shortf,intf:CF1.intf,longf:CF1.longf,floatf:CF1.floatf,doublef:CF1.doublef" ZKHost = "cloudtable-cf82-zk3-pa6HnHpf.cloudtable.com:2181,cloudtable-cf82-zk2-weBkIrjI.cloudtable.com:2181, cloudtable-cf82-zk1- WY09px9l.cloudtable.com:2181" // select jdbcDF = sparkSession.read.schema(schema)\ .format("hbase")\ .option("ZKHost",ZKHost)\ .option("TableName",TableName)\ .option("RowKey",RowKey)\ .option("Cols",Cols)\ .load() jdbcDF.filter("id = '12333' or id='11111'").show()
Note
The length of id, location, and city parameter is limited. When inserting data, you must set the data values based on the required length. Otherwise, an encoding format error occurs during query.
Submitting a Spark job
Upload the Python code file to DLI.
(Optional) Add the krb5.conf and user.keytab files to other dependency files of the job when creating a Spark job in an MRS cluster with Kerberos authentication enabled. Skip this step if Kerberos authentication is not enabled for the cluster.
In the Spark job editor, select the corresponding dependency module and execute the Spark job.
Note
If the Spark version is 2.3.2 (will be offline soon) or 2.4.5, specify the Module to sys.datasource.hbase when you submit a job.
If the Spark version is 3.1.1, you do not need to select a module. Configure Spark parameters (--conf).
spark.driver.extraClassPath=/usr/share/extension/dli/spark-jar/datasource/hbase/*
spark.executor.extraClassPath=/usr/share/extension/dli/spark-jar/datasource/hbase/*
Complete Example Code¶
Connecting to MRS HBase through SQL APIs
Sample code when Kerberos authentication is disabled
# _*_ coding: utf-8 _*_ from __future__ import print_function from pyspark.sql.types import StructType, StructField, IntegerType, StringType, BooleanType, ShortType, LongType, FloatType, DoubleType from pyspark.sql import SparkSession if __name__ == "__main__": # Create a SparkSession session. sparkSession = SparkSession.builder.appName("datasource-hbase").getOrCreate() sparkSession.sql( "CREATE TABLE testhbase(id STRING, location STRING, city STRING) using hbase OPTIONS (\ 'ZKHost' = '192.168.0.189:2181',\ 'TableName' = 'hbtest',\ 'RowKey' = 'id:5',\ 'Cols' = 'location:info.location,city:detail.city')") sparkSession.sql("insert into testhbase values('95274','abc','Jinan')") sparkSession.sql("select * from testhbase").show() # close session sparkSession.stop()
Sample code when Kerberos authentication is enabled
# _*_ coding: utf-8 _*_ from __future__ import print_function from pyspark import SparkFiles from pyspark.sql import SparkSession import shutil import time import os if __name__ == "__main__": # Create a SparkSession session. sparkSession = SparkSession.builder.appName("Test_HBase_SparkSql_Kerberos").getOrCreate() sc = sparkSession.sparkContext time.sleep(10) krb5_startfile = SparkFiles.get("krb5.conf") keytab_startfile = SparkFiles.get("user.keytab") path_user = os.getcwd() krb5_endfile = path_user + "/" + "krb5.conf" keytab_endfile = path_user + "/" + "user.keytab" shutil.copy(krb5_startfile, krb5_endfile) shutil.copy(keytab_startfile, keytab_endfile) time.sleep(20) sparkSession.sql( "CREATE TABLE testhbase(id string,booleanf boolean,shortf short,intf int,longf long,floatf float,doublef double) " + "using hbase OPTIONS(" + "'ZKHost'='10.0.0.146:2181'," + "'TableName'='hbtest'," + "'RowKey'='id:100'," + "'Cols'='booleanf:CF1.booleanf,shortf:CF1.shortf,intf:CF1.intf,longf:CF2.longf,floatf:CF1.floatf,doublef:CF2.doublef'," + "'krb5conf'='" + path_user + "/krb5.conf'," + "'keytab'='" + path_user+ "/user.keytab'," + "'principal'='krbtest') ") sparkSession.sql("insert into testhbase values('95274','abc','Jinan')") sparkSession.sql("select * from testhbase").show() # close session sparkSession.stop()
Connecting to HBase through DataFrame APIs
# _*_ coding: utf-8 _*_ from __future__ import print_function from pyspark.sql.types import StructType, StructField, IntegerType, StringType, BooleanType, ShortType, LongType, FloatType, DoubleType from pyspark.sql import SparkSession if __name__ == "__main__": # Create a SparkSession session. sparkSession = SparkSession.builder.appName("datasource-hbase").getOrCreate() # Createa data table for DLI-associated ct sparkSession.sql(\ "CREATE TABLE test_hbase(id STRING, location STRING, city STRING, booleanf BOOLEAN, shortf SHORT, intf INT, longf LONG,floatf FLOAT,doublef DOUBLE) using hbase OPTIONS ( \ 'ZKHost' = 'cloudtable-cf82-zk3-pa6HnHpf.cloudtable.com:2181,\ cloudtable-cf82-zk2-weBkIrjI.cloudtable.com:2181,\ cloudtable-cf82-zk1-WY09px9l.cloudtable.com:2181',\ 'TableName' = 'table_DupRowkey1',\ 'RowKey' = 'id:5,location:6,city:7',\ 'Cols' = 'booleanf:CF1.booleanf,shortf:CF1.shortf,intf:CF1.intf,longf:CF1.longf,floatf:CF1.floatf,doublef:CF1.doublef')") # Create a DataFrame and initialize the DataFrame data. dataList = sparkSession.sparkContext.parallelize([("11111", "aaa", "aaa", False, 4, 3, 23, 2.3, 2.34)]) # Setting schema schema = StructType([StructField("id", StringType()), StructField("location", StringType()), StructField("city", StringType()), StructField("booleanf", BooleanType()), StructField("shortf", ShortType()), StructField("intf", IntegerType()), StructField("longf", LongType()), StructField("floatf", FloatType()), StructField("doublef", DoubleType())]) # Create a DataFrame from RDD and schema dataFrame = sparkSession.createDataFrame(dataList, schema) # Write data to the cloudtable-hbase dataFrame.write.insertInto("test_hbase") # Set cross-source connection parameters TableName = "table_DupRowkey1" RowKey = "id:5,location:6,city:7" Cols = "booleanf:CF1.booleanf,shortf:CF1.shortf,intf:CF1.intf,longf:CF1.longf,floatf:CF1.floatf,doublef:CF1.doublef" ZKHost = "cloudtable-cf82-zk3-pa6HnHpf.cloudtable.com:2181,cloudtable-cf82-zk2-weBkIrjI.cloudtable.com:2181, cloudtable-cf82-zk1-WY09px9l.cloudtable.com:2181" # Read data on CloudTable-HBase jdbcDF = sparkSession.read.schema(schema)\ .format("hbase")\ .option("ZKHost", ZKHost)\ .option("TableName",TableName)\ .option("RowKey", RowKey)\ .option("Cols", Cols)\ .load() jdbcDF.filter("id = '12333' or id='11111'").show() # close session sparkSession.stop()