Tuesday, February 12, 2019

Error accessing DB: (2059, "Authentication plugin 'caching_sha2_password' cannot be loaded: /usr/lib64/mysql/plugin caching_sha2_password.so: cannot open shared object file: No such file or directory")

Hue error with MySQL 8:

Error accessing DB: (2059, "Authentication plugin 'caching_sha2_password' cannot be loaded: /usr/lib64/mysql/plugin caching_sha2_password.so: cannot open shared object file: No such file or directory")

To fix: 

ALTER USER hue IDENTIFIED WITH mysql_native_password BY 'password';

Saturday, February 2, 2019

Display lP address of machine on the banner without login

Add following lines to /etc/rc.local:

# initial setup, cp /etc/issue /etc/issue.orig
cp /etc/issue.orig /etc/issue
ip addr|grep inet |grep -i enp|awk {'print $NF, $2'}|awk -F'/' {'print $1'} >> /etc/issue
echo "" >> /etc/issue

Monday, December 31, 2018

Demo code to show case Solr ingestion

# Written for Solr 7 (shipped with CDH6) and Python3

import tika
import json
import urllib3
import traceback
import os

from tika import parser
url = 'http://node02.dbaglobe.com:8983/solr/cms/update/json/docs?commit=true'
filelist = ['D:\\Temp\\Building Positive Relationships young children.pdf',
            'D:\\Temp\\Building Positive Relationships spouse n in laws.pdf']

http = urllib3.PoolManager()

for file in filelist:
        parsed = parser.from_file(file)
        #Add content to "combined" dict object        combined={}
        combined['id']=os.path.basename(file) # use file name as Doc ID        combined.update(parsed["metadata"])
        combined_json = json.loads(json.dumps(combined))


        # to clean up, execute solr command *:*        # use immutable to avoid error "This ConfigSet is immutable.", use below to create the template before create the collection        # http://node02:8983/solr/admin/configs?action=CREATE&name=myConfigSet&baseConfigSet=schemalessTemplate&configSetProp.immutable=false&wt=xml        # to search: content:"Psychologist"
        response = http.request('POST',url,body=json.dumps(combined_json),headers={'Content-Type': 'application/json'})
        print (response.data)

Sunday, December 16, 2018

Sentry and Hive permission explained

When using Sentry, the impersonation feature of HiveServer2 is disabled and each query runs in the cluster as the configured Hive principal. Thus, each HDFS location associated with a Hive table should be readable and writable by the Hive user or group.
If you are using the HDFS ACL synchronization feature, the required HDFS permissions (r-x for SELECT-wx for INSERT, and rwx for ALL) on files are enforced automatically and maintained dynamically in response to changes in privilege grants on databases and tables. In our example, the alice user would be given r-x permission to files in tables in the sales database. Note that a grant on a URI object does not result in corresponding permissions on the location in HDFS.

Saturday, October 13, 2018

Tweet Read Example with PySpark streaming analytics


import tweepy
from tweepy import Stream
from tweepy.auth import OAuthHandler
from tweepy.streaming import StreamListener
import socket
import json

consumer_key = ''consumer_secret = ''access_token = ''access_secret = ''

class TweetsListener(StreamListener):

    def __init__(self, csocket):
        self.client_socket = csocket

    def on_data(self, data):
            msg = json.loads(data)
            return True        except BaseException as e:
            print("Error on data: %s" % str(e))
        return True
    def on_error(self, status):
        return True

def sendData(c_socket):
    auth = OAuthHandler(consumer_key, consumer_secret)
    auth.set_access_token(access_token, access_secret)

    twitter_stream = Stream(auth, TweetsListener(c_socket))

if __name__ == "__main__":
    s = socket.socket()  # create socket object    host = ""    port = 5555    s.bind((host, port))
    print("Listening on port: %s" % str(port))

    c, addr = s.accept()
    print("Received request from: " + str(addr))



import findspark


from pyspark import SparkContext
from pyspark.streaming import StreamingContext
from pyspark.sql import SQLContext
from pyspark.sql.functions import desc

# Not required if running in Pyspark integrated notebooksc = SparkContext()

ssc = StreamingContext(sc, 10)
sqlContext = SQLContext(sc)

socket_stream = ssc.socketTextStream("",5555)

lines = socket_stream.window(20)

from collections import namedtuple
fields = ("tag","count")
Tweet = namedtuple('Tweet', fields)

# use () for multiple lines(lines.flatMap(lambda text: text.split(" "))
.filter(lambda word: word.startswith("#"))
.map(lambda word: (word.lower(), 1))
.reduceByKey(lambda a, b : a + b)
.map(lambda rec: Tweet(rec[0],rec[1]))
.foreachRDD(lambda rdd: rdd.toDF().sort(desc("count"))

import time
from IPython import display
import matplotlib.pyplot as plt
import seaborn as sns
import pandas
# get_ipython().run_line_magic('matplotlib', 'inline')


count = 0while count < 10:
    top_10_tweets = sqlContext.sql("select tag,count from tweets")
    top_10_df = top_10_tweets.toPandas()
    display.clear_output(wait = True)
    plt.figure(figsize= (10, 8))
    sns.barplot(x="count", y="tag",data=top_10_df)
    count = count+1

Wednesday, October 10, 2018

Use Jupyter Notebook with Spark2 on Apache Spark on MacOS

Reference url: http://www.dbaglobe.com/2018/07/use-jupyter-notebook-with-spark2-on.html

Below are changes specific for apache spark, anaconda3 on MacOS

mkdir /Users/donghua/anaconda3/share/jupyter/kernels/pyspark2/

[root@cdh-vm bin]# cat  /Users/donghua/anaconda3/share/jupyter/kernels/pyspark2/kernel.json
      "argv": [
      "display_name": "Python3.6 + Pyspark(Spark 2.3.2)",
      "language": "python",
      "env": {
        "PYSPARK_PYTHON": "python",
        "SPARK_HOME": "/Users/donghua/spark-2.3.2-bin-hadoop2.7",
        "SPARK_CONF_DIR": "/Users/donghua/spark-2.3.2-bin-hadoop2.7/conf",
        "PYTHONPATH": "/Users/donghua/spark-2.3.2-bin-hadoop2.7/python/lib/py4j-0.10.7-src.zip:/Users/donghua/spark-2.3.2-bin-hadoop2.7/python/:",
        "PYTHONSTARTUP": "/Users/donghua/spark-2.3.2-bin-hadoop2.7/python/pyspark/shell.py",
        "PYSPARK_SUBMIT_ARGS": "--master spark://Donghuas-MacBook-Air.local:7077 --name PySparkShell pyspark-shell"

/Users/donghua/anaconda3//bin/jupyter-notebook --ip=Donghuas-MacBook-Air.local --port 9999

#export SPARK_HOME=/Users/donghua/spark-2.3.2-bin-hadoop2.7

Tuesday, October 9, 2018

Modify default slaves.sh to start apache-spark on MacOS

By default, Apache Spark sbin/start-all.sh will try to start worker using "ssh" to slave node, regardless we were testing using our laptop. Below modification is to start it using Bash instead of SSH.

Donghuas-MacBook-Air:sbin donghua$ diff slaves.sh slaves.sh.old
<       cmd="${@// /\\ } 2>&1"
<       echo $cmd
<       bash -c "$cmd"
>     ssh $SPARK_SSH_OPTS "$slave" $"${@// /\\ }" \
>       2>&1 | sed "s/^/$slave: /"
<       cmd="${@// /\\ } 2>&1"
<       echo $cmd
<       bash -c "$cmd"
>     ssh $SPARK_SSH_OPTS "$slave" $"${@// /\\ }" \
>       2>&1 | sed "s/^/$slave: /" &

Revised code could be found here:


And modified version of spark-conf.sh to start multiple workers could be found here: