[ARROW-15803] [R] Empty JSON object parsed as corrupt data frame

• Type: Bug
• Status: Open
• Priority: Major
• Resolution: Unresolved
• Affects Version/s: 7.0.0
• Component/s: R
• External issue URL: https://github.com/apache/arrow/issues/31244

Language

R

• Assignee: Unassigned
• Reporter: Will Jones
• Created: 28/Feb/22 16:48
• Updated: 11/Jan/23 11:39

Description

If you have a JSON object field that is always empty, it seems to be not handled well, whether or not a schema is provided that tells Arrow what should be in that object.

library(arrow)
#> 
#> Attaching package: 'arrow'
#> The following object is masked from 'package:utils':
#> 
#>     timestamp

json_val <- '{
  "rows": [
    {"empty": {} },
    {"empty": {} },
    {"empty": {} }
  ]
}'
# Remove newlines
json_val <- gsub("\n", "", json_val)

json_file <- tempfile()
writeLines(json_val, json_file)

schema <- schema(field("rows", list_of(struct(empty = struct(y = int32())))))
raw <- read_json_arrow(json_file, schema=schema)
raw$rows$empty
#> Error: Corrupt x: no names