Aggs query to data.table

Given some raw JSON from an aggs query in Elasticsearch, parse the aggregations into a data.table.

Usage

chomp_aggs(aggs_json = NULL)

Arguments

aggs_json

A character vector. If its length is greater than 1, its elements will be pasted together. This can contain a JSON returned from an aggs query in Elasticsearch, or a filepath or URL pointing at one.

Value

A data.table representation of the result or NULL if the aggregation result is empty.

Examples

# A sample raw result from an aggs query combining date_histogram and extended_stats:
result <- '{"aggregations":{"dateTime":{"buckets":[{"key_as_string":"2016-12-01T00:00:00.000Z",
"key":1480550400000,"doc_count":123,"num_potatoes":{"count":120,"min":0,"max":40,"avg":15,
"sum":1800,"sum_of_squares":28000,"variance":225,"std_deviation":15,"std_deviation_bounds":{
"upper":26,"lower":13}}},{"key_as_string":"2017-01-01T00:00:00.000Z","key":1483228800000,
"doc_count":134,"num_potatoes":{"count":131,"min":0,"max":39,"avg":16,"sum":2096,
"sum_of_squares":34000,"variance":225,"std_deviation":15,"std_deviation_bounds":{"upper":26,
"lower":13}}}]}}}'

# Parse into a data.table
aggDT <- chomp_aggs(aggs_json = result)
print(aggDT)
#>                    dateTime num_potatoes.count num_potatoes.min
#>                      <char>              <int>            <int>
#> 1: 2016-12-01T00:00:00.000Z                120                0
#> 2: 2017-01-01T00:00:00.000Z                131                0
#>    num_potatoes.max num_potatoes.avg num_potatoes.sum
#>               <int>            <int>            <int>
#> 1:               40               15             1800
#> 2:               39               16             2096
#>    num_potatoes.sum_of_squares num_potatoes.variance num_potatoes.std_deviation
#>                          <int>                 <int>                      <int>
#> 1:                       28000                   225                         15
#> 2:                       34000                   225                         15
#>    num_potatoes.std_deviation_bounds.upper
#>                                      <int>
#> 1:                                      26
#> 2:                                      26
#>    num_potatoes.std_deviation_bounds.lower doc_count
#>                                      <int>     <int>
#> 1:                                      13       123
#> 2:                                      13       134