Generate the aggregated key from input values and output to Redis's SET value.

This plugin is designed to extract data set diff files used with the combination in below use cases.

1. Use this plugin and output specified key's to redis.
   • this plugin.
2. Input another data source and use filter key_in_redis plugin with specified key's then filtered the key's (or that hash).
   • https://github.com/smdmts/embulk-filter-key_in_redis

• Plugin type: output
• Load all or nothing: no
• Resume supported: no
• Cleanup supported: no

• input json

{  
   "device_id":"ABC",
   "timestamp_micros":1502590079312009,
   "params":{  
      "UserID":"user_id_12345"
   }
}

• definition's yaml

filters:
  - type: expand_json
    json_column_name: record
    root: "$."
    stop_on_invalid_record: false
    expanded_columns:
      - { name: "device_id", type: string }
      - { name: "timestamp_micros", type: long }
      - { name: "params", type: json }
out:
  type: "key_to_redis"
  redis_set_key: redis_key
  flush_on_start: true
  put_as_md5: false
  appender: "_"
  key_with_index: 
    1: "device_id"
    2: "timestamp_micros"
  json_key_with_index:
    3: "UserID" 

• output as redis command

sadd redis_key "ABC_1502590079312009_user_id_12345"

$ ./gradlew gem  # -t to watch change of files and rebuild continuously