jsonedit

R bindings to node-jsonc-parser to modify or format JSON files while retaining comments.

Installation

You can install the development version of jsonedit like so:

pak::pak("r-lib/jsonedit")

Example

library(jsonedit)

text <- '
{
  "[r]": {
    // Important comment
    "editor.formatOnSave": true,
    "editor.defaultFormatter": "Posit.air-vscode"
  },
  "files.trimFinalNewlines": true,
  "editor.rulers": [
    80,
    100
  ], // A trailing comma
}
'

Parse an entire file worth of text with text_parse() or file_parse():

text_parse(text)
#> $`[r]`
#> $`[r]`$editor.formatOnSave
#> [1] TRUE
#> 
#> $`[r]`$editor.defaultFormatter
#> [1] "Posit.air-vscode"
#> 
#> 
#> $files.trimFinalNewlines
#> [1] TRUE
#> 
#> $editor.rulers
#> $editor.rulers[[1]]
#> [1] 80
#> 
#> $editor.rulers[[2]]
#> [1] 100

Parse a target JSON path with text_parse_at_path() or file_parse_at_path():

text_parse_at_path(text, c("[r]", "editor.formatOnSave"))
#> [1] TRUE

# The 2nd ruler in the array
text_parse_at_path(text, list("editor.rulers", 2))
#> [1] 100

Modify a JSON file, retaining comments, using text_modify() and file_modify():

# A new field
cat(text_modify(text, "new", 1))
#> 
#> {
#>   "[r]": {
#>     // Important comment
#>     "editor.formatOnSave": true,
#>     "editor.defaultFormatter": "Posit.air-vscode"
#>   },
#>   "files.trimFinalNewlines": true,
#>   "editor.rulers": [
#>     80,
#>     100
#> ],
#> "new": 1, // A trailing comma
#> }

# Modify an existing path, retaining comments
cat(text_modify(text, c("[r]", "editor.formatOnSave"), FALSE))
#> 
#> {
#>   "[r]": {
#>     // Important comment
#>     "editor.formatOnSave": false,
#>     "editor.defaultFormatter": "Posit.air-vscode"
#>   },
#>   "files.trimFinalNewlines": true,
#>   "editor.rulers": [
#>     80,
#>     100
#>   ], // A trailing comma
#> }

# Modify an array by position

# Replacement:
cat(text_modify(text, list("editor.rulers", 2), 20))
#> 
#> {
#>   "[r]": {
#>     // Important comment
#>     "editor.formatOnSave": true,
#>     "editor.defaultFormatter": "Posit.air-vscode"
#>   },
#>   "files.trimFinalNewlines": true,
#>   "editor.rulers": [
#>     80,
#>     20
#>   ], // A trailing comma
#> }

# Insertion:
options <- modification_options(is_array_insertion = TRUE)
cat(text_modify(
  text,
  list("editor.rulers", 2),
  20,
  modification_options = options
))
#> 
#> {
#>   "[r]": {
#>     // Important comment
#>     "editor.formatOnSave": true,
#>     "editor.defaultFormatter": "Posit.air-vscode"
#>   },
#>   "files.trimFinalNewlines": true,
#>   "editor.rulers": [
#>     80,
#>     20,
#>     100
#>   ], // A trailing comma
#> }

# Insertion at back (when you don't know the number of existing elements)
cat(text_modify(text, list("editor.rulers", -1), 20))
#> 
#> {
#>   "[r]": {
#>     // Important comment
#>     "editor.formatOnSave": true,
#>     "editor.defaultFormatter": "Posit.air-vscode"
#>   },
#>   "files.trimFinalNewlines": true,
#>   "editor.rulers": [
#>     80,
#>     100,
#>     20
#>   ], // A trailing comma
#> }