Read a file with one valid JSON object per line with R and jsonlite
We have a file with one valid JSON objects per line which we will load using jsonlite
library(jsonlite)
jsonString <- '{"score": 10, "info": { "name": "Stefan", "website": "stefanengineering.com"}}
{"score": 12, "info": { "name": "Lars"}}'
# If reading from a file, use con <- file(filename)
con <- textConnection(jsonString)
(res <- stream_in(con))
#>
#> Found 2 records...
#> Imported 2 records. Simplifying...
#> score info.name info.website
#> 1 10 Stefan stefanengineering.com
#> 2 12 Lars <NA>
# Nested objects are stored as data frames
sapply(res, class)
#> score info
#> "integer" "data.frame"By default, the nested objects are stored as nested data frames.
The function jsonlite::flatten will flatten the resulting data frame.
Note that jsonlite imports purrr which has its own version of flatten.
# Flatten the nested data frames
# Use the jsonlite flatten rather than purrr flatten
(flatRes <- jsonlite::flatten(res))
#> score info.name info.website
#> 1 10 Stefan stefanengineering.com
#> 2 12 Lars <NA>
sapply(flatRes, class)
#> score info.name info.website
#> "integer" "character" "character"