Write a list to .json, .json.gz, or both – byte-equal by construction

Serialises data_list to JSON text once and writes that single in-memory string to either the plain .json file, the gzipped .json.gz file, or both – as selected by the write_json and write_gz arguments. Because both outputs are written from the same byte string, the .json.gz always decompresses to a file byte- identical to the .json (when both are produced); the pair cannot drift.

Replaces the older write_json_with_optional_gz() "sidecar" model. Both flags are first-class peers: any combination except write_json = FALSE, write_gz = FALSE is allowed.

Usage

write_json_or_gz(data_list, file_path, write_json = TRUE, write_gz = FALSE)

Arguments

data_list

Named list to serialise.

file_path

Base output path. Must end in .json. The .gz output (if write_gz = TRUE) is written to paste0(file_path, ".gz").

write_json

Logical. If TRUE (default), write the plain .json file.

write_gz

Logical. If TRUE, write the gzipped .json.gz file. Default FALSE.

Value

The base file_path (invisibly).

Details

Both files come from a single jsonlite::toJSON() call. There is no parallel serialisation, no patch-and-rewrite loop, and no possibility for the .json and .json.gz to diverge.

At least one of write_json / write_gz must be TRUE; passing both as FALSE errors immediately (the function would otherwise produce nothing).

See also

write_list_to_json()

Examples

if (FALSE) { # \dontrun{
  # Plain JSON only (default)
  write_json_or_gz(my_config, "config.json")

  # gzip only
  write_json_or_gz(my_config, "config.json", write_json = FALSE, write_gz = TRUE)

  # Both, guaranteed byte-equal
  write_json_or_gz(my_config, "config.json", write_json = TRUE, write_gz = TRUE)
} # }