sparking water

2 It provides a way to initialize H2O services on each node in the Spark cluster and to access data stored in data structures of Spark and H2O.

3 Internal Backend is easiest to deploy; however when Spark or YARN kills the executor - which is not an unusual case - the entire H2O cluster goes down because H2O does not support high availability.

4 The internal backend is the default for behavior for Sparkling Water. Another way to change type of backend is by calling the setExternalClusterMode() or setInternalClusterMode() method on the H2OConf class. H2OConf is simple wrapper around SparkConf and inherits all properties in the Spark configuration.

5 好像在安装sparkingwater时，就会把pyspark和H2O装好： pip install h2o_pysparkling_2.3

=======================

1 启动spark : ./sbin/start-master.sh ./sbin/start-slave.sh spark://zcy-VirtualBox:7077

2 可以先运行一个很简单的脚本，看环境是否ready ，为了运行成功，需要把虚拟机内存调大（我改成了2g）

from pysparkling import *
from pyspark.sql import SparkSession
import h2o

# Initiate SparkSession
spark = SparkSession.builder.appName("App name").getOrCreate()

# Initiate H2OContext
hc = H2OContext.getOrCreate(spark)

# Stop H2O and Spark services
h2o.cluster().shutdown()
spark.stop()
print "111111111111"

./bin/spark-submit --master spark://zcy-VirtualBox:7077 --conf "spark.executor.memory=1g" /home/zcy/working/tst.py

结果如下

3 运行一个稍微复杂的脚本：

import h2o
from datetime import datetime

from pyspark import SparkConf, SparkFiles
from pyspark.sql import Row, SparkSession
import os
from pysparkling import *

# Refine date column
def refine_date_col(data, col):
    data["Day"] = data[col].day()
    data["Month"] = data[col].month()
    data["Year"] = data[col].year()
    data["WeekNum"] = data[col].week()
    data["WeekDay"] = data[col].dayOfWeek()
    data["HourOfDay"] = data[col].hour()
    
    # Create weekend and season cols
    # Spring = Mar, Apr, May. Summer = Jun, Jul, Aug. Autumn = Sep, Oct. Winter = Nov, Dec, Jan, Feb.
    # data["Weekend"]   = [1 if x in ("Sun", "Sat") else 0 for x in data["WeekDay"]]
    data["Weekend"] = ((data["WeekDay"] == "Sun") | (data["WeekDay"] == "Sat"))
    data["Season"] = data["Month"].cut([0, 2, 5, 7, 10, 12], ["Winter", "Spring", "Summer", "Autumn", "Winter"])


# This is just helper function returning path to data-files
def _locate(file_name):
    if os.path.isfile("/home/zcy/working/data_tst/" + file_name):
        return "/home/zcy/working/data_tst/" + file_name
    else:
        print "eeeeeeeeeeee"


spark = SparkSession.builder.appName("ChicagoCrimeTest").getOrCreate()
# Start H2O services
h2oContext = H2OContext.getOrCreate(spark)
# Define file names
chicagoAllWeather = "chicagoAllWeather.csv"
chicagoCensus = "chicagoCensus.csv"
chicagoCrimes10k = "chicagoCrimes10k.csv.zip"


# h2o.import_file expects cluster-relative path
f_weather = h2o.upload_file(_locate(chicagoAllWeather))
f_census = h2o.upload_file(_locate(chicagoCensus))
f_crimes = h2o.upload_file(_locate(chicagoCrimes10k))
print "111111111111"

# Transform weather table
# Remove 1st column (date)
f_weather = f_weather[1:]

# Transform census table
# Remove all spaces from column names (causing problems in Spark SQL)
col_names = list(map(lambda s: s.strip().replace(' ', '_').replace('+', '_'), f_census.col_names))

# Update column names in the table
# f_weather.names = col_names
f_census.names = col_names


# Transform crimes table
# Drop useless columns
f_crimes = f_crimes[2:]

# Set time zone to UTC for date manipulation
h2o.cluster().timezone = "Etc/UTC"

# Replace ' ' by '_' in column names
col_names = list(map(lambda s: s.replace(' ', '_'), f_crimes.col_names))
f_crimes.names = col_names
refine_date_col(f_crimes, "Date")
f_crimes = f_crimes.drop("Date")

# Expose H2O frames as Spark DataFrame
print "22222222222222"
df_weather = h2oContext.as_spark_frame(f_weather)
df_census = h2oContext.as_spark_frame(f_census)
df_crimes = h2oContext.as_spark_frame(f_crimes)

# Register DataFrames as tables
df_weather.createOrReplaceTempView("chicagoWeather")
df_census.createOrReplaceTempView("chicagoCensus")
df_crimes.createOrReplaceTempView("chicagoCrime")

crimeWithWeather = spark.sql("""SELECT
a.Year, a.Month, a.Day, a.WeekNum, a.HourOfDay, a.Weekend, a.Season, a.WeekDay,
a.IUCR, a.Primary_Type, a.Location_Description, a.Community_Area, a.District,
a.Arrest, a.Domestic, a.Beat, a.Ward, a.FBI_Code,
b.minTemp, b.maxTemp, b.meanTemp,
c.PERCENT_AGED_UNDER_18_OR_OVER_64, c.PER_CAPITA_INCOME, c.HARDSHIP_INDEX,
c.PERCENT_OF_HOUSING_CROWDED, c.PERCENT_HOUSEHOLDS_BELOW_POVERTY,
c.PERCENT_AGED_16__UNEMPLOYED, c.PERCENT_AGED_25__WITHOUT_HIGH_SCHOOL_DIPLOMA
FROM chicagoCrime a
JOIN chicagoWeather b
ON a.Year = b.year AND a.Month = b.month AND a.Day = b.day
JOIN chicagoCensus c
ON a.Community_Area = c.Community_Area_Number""")

# Publish Spark DataFrame as H2OFrame with given name
crimeWithWeatherHF = h2oContext.as_h2o_frame(crimeWithWeather, "crimeWithWeatherTable")
print "3333333333333333333"
# Transform selected String columns to categoricals
cat_cols = ["Arrest", "Season", "WeekDay", "Primary_Type", "Location_Description", "Domestic"]
for col in cat_cols :
    crimeWithWeatherHF[col] = crimeWithWeatherHF[col].asfactor()
    
# Split frame into two - we use one as the training frame and the second one as the validation frame
splits = crimeWithWeatherHF.split_frame(ratios=[0.8])
train = splits[0]
test = splits[1]
print "4444444444444444"
h2o.download_csv(train,'/home/zcy/working/data_tst/ret/train.csv')
h2o.download_csv(test,'/home/zcy/working/data_tst/ret/test.csv')

# stop H2O and Spark services
h2o.cluster().shutdown()
spark.stop()

3 运行脚本，

./bin/spark-submit --master spark://zcy-VirtualBox:7077 --conf "spark.executor.memory=1g" /home/zcy/working/sparkH2O.py