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Reading OpenData JSON and Storing into Apache HBase / Phoenix Tables - Part 1

JSON Batch to Single Row Phoenix
I grabbed open data on Crime from Philly's Open Data (https://www.opendataphilly.org/dataset/crime-incidents), after a free sign up you get access to JSON crime data (https://data.phila.gov/resource/sspu-uyfa.json) You can grab individual dates or ranges for thousands of records. I wanted to spool each JSON record as a separate HBase row. With the flexibility of Apache NiFi 1.0.0, I can specify run times via cron or other familiar setup. This is my master flow.
First I use GetHTTP to retrieve the SSL JSON messages, I split the records up and store them as RAW JSON in HDFS as well as send some of them via Email, format them for Phoenix SQL and store them in Phoenix/HBase. All with no coding and in a simple flow. For extra output, I can send them to Reimann server for monitoring.
Setting up SSL for accessing HTTPS data like Philly Crime, require a little configuration and knowing what Java JRE you are using to run NiFi. You can run service nifi status to quickly get which JRE.
Split the Records
The Open Data set has many rows of data, let's split them up and pull out the attributes we want from the JSON.
Phoenix
Another part that requires specific formatting is setting up the Phoenix connection. Make sure you point to the correct driver and if you have security make sure that is set.
Load the Data (Upsert)
Once your data is loaded you can check quickly with /usr/hdp/current/phoenix-client/bin/sqlline.py localhost:2181:/hbase-unsecure
The SQL for this data set is pretty straight forward.
  1. CREATE TABLE phillycrime (dc_dist varchar,
  2. dc_key varchar not null primary key,dispatch_date varchar,dispatch_date_time varchar,dispatch_time varchar,hour varchar,location_block varchar,psa varchar,
  3. text_general_code varchar,ucr_general varchar);
  4.  
  5.  
  6. {"dc_dist":"18","dc_key":"200918067518","dispatch_date":"2009-10-02","dispatch_date_time":"2009-10-02T14:24:00.000","dispatch_time":"14:24:00","hour":"14","location_block":"S 38TH ST / MARKETUT ST","psa":"3","text_general_code":"Other Assaults","ucr_general":"800"}
  7. upsert into phillycrime values ('18', '200918067518', '2009-10-02','2009-10-02T14:24:00.000','14:24:00','14', 'S 38TH ST / MARKETUT ST','3','Other Assaults','800');
  8. !tables
  9. !describe phillycrime
The DC_KEY is unique so I used that as the Phoenix key. Now all the data I get will be added and any repeats will safely update. Sometimes during the data we may reget some of the same data, that's okay, it will just update to the same value.