fromJSON simplification

simplify.R

library(jsonlite)

txt <- '{
  "points": [{
  "curveNumber": 0, 
  "text": "a", 
  "pointNumber": 0, 
  "customdata": "c.a", 
  "y": 4, 
  "x": 1
}, {
  "curveNumber": 1, 
  "text": "w", 
  "pointNumber": 0, 
  "customdata": "c.w", 
  "y": 9, 
  "x": 1
}]
}'

# the desired "return value"
str(fromJSON(txt))

#> List of 1
#>   $ points:'data.frame':	2 obs. of  6 variables:
#>     ..$ curveNumber: int [1:2] 0 1
#>     ..$ text       : chr [1:2] "a" "w"
#>     ..$ pointNumber: int [1:2] 0 0
#>     ..$ customdata : chr [1:2] "c.a" "c.w"
#>     ..$ y          : int [1:2] 4 9
#>     ..$ x          : int [1:2] 1 1


txt2 <- '
{"output":{"id":"hover-data","property":"children"},"inputs":[{"id":"basic-interactions","property":"hoverData","value":{"points":[{"curveNumber":0,"pointNumber":0,"x":1,"y":4,"customdata":"c.a","text":"a"},{"curveNumber":1,"pointNumber":0,"x":1,"y":9,"customdata":"c.w","text":"w"}]}}]}
'

# due simplification rules, we get an awkward return value
str(fromJSON(txt2)$inputs$value)

#> 'data.frame':	1 obs. of  1 variable:
#>   $ points:List of 1
#>     ..$ :'data.frame':	2 obs. of  6 variables:
#>     .. ..$ curveNumber: int  0 1
#>     .. ..$ pointNumber: int  0 0
#>     .. ..$ x          : int  1 1
#>     .. ..$ y          : int  4 9
#>     .. ..$ customdata : chr  "c.a" "c.w"
#>     .. ..$ text       : chr  "a" "w"

# we can, however, avoid simplication at first, obtain the 'return' value,
# then simplify it
value <- fromJSON(txt2, simplifyVector = FALSE)$inputs[[1]]$value
str(jsonlite:::simplify(value))

#> List of 1
#>   $ points:'data.frame':	2 obs. of  6 variables:
#>     ..$ curveNumber: int [1:2] 0 1
#>     ..$ pointNumber: int [1:2] 0 0
#>     ..$ x          : int [1:2] 1 1
#>     ..$ y          : int [1:2] 4 9
#>     ..$ customdata : chr [1:2] "c.a" "c.w"
#>     ..$ text       : chr [1:2] "a" "w"