I’ve been playing around with script fields to manipulate data returned by ElasticSearch queries. As an example, data where there are a few nested objects with values that need to be multiplied together:
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 | { "order": { "item1": { "cost": 31.55, "count": 111 }, "item2": { "cost": 62.55, "count": 222 }, "item3": { "cost": 93.55, "count": 333 } }} |
And to retrieve records and multiply cost by count:
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 | { "query" : { "match_all" : {} }, "_source": ["order.item*.item", "order.item*.count", "order.item*.cost"], "script_fields" : { "total_cost_1" : { "script" : { "lang": "painless", "source": "return doc['order.item1.cost'].value * doc['order.item1.count'].value;" } }, "total_cost_2" : { "script" : { "lang": "painless", "source": "return doc['order.item2.cost'].value * doc['order.item2.count'].value;" } }, "total_cost_3" : { "script" : { "lang": "painless", "source": "return doc['order.item3.cost'].value * doc['order.item3.count'].value;" } } }} |
Unfortunately, I cannot find any way to iterate across an arbitrary number of item# objects nested in the order object. So, for now, I think the data manipulation will be done in the program using the API to retrieve data. Still, it was good to learn how to address values in the doc record.