Parse a JSON file or string into a tsjson object

Parse a JSON file or string and create a tsjson object that represents its document. This object can then be queried and manipulated.

Usage

load_json(file = NULL, text = NULL, ranges = NULL, options = NULL)

Arguments

file

Path of a JSON file. Use either file or text.

text

JSON string. Use either file or text.

ranges

Can be used to parse part(s) of the input. It must be a data frame with integer columns start_row, start_col, end_row, end_col, start_byte, end_byte, in this order.

options

List of options, see tsjson_options(). This argument must be named and cannot be abbreviated.

Value

A tsjson object.

Details

tsjson objects have format() and print() methods to pretty-print them to the screen.

They can be converted to a data frame using the single bracket operator.

See also

select() to select part(s) of a tsjson object, unserialize_selected() to extract the selected part(s), format_selected() to format the selected part(s), delete_selected(), insert_into_selected() and update_selected() to manipulate it. save_json() to save the JSON document to a file.

Examples

text <- '
{
  "a": 1,
  "b": [2, 3, 4],
  "[r]": {
    "this": "setting",
    // A comment!
    "that": true
  }
}
'

# Parse the JSON, allowing comments (i.e. JSONC)
load_json(text = text)
#> # json (10 lines)
#>  1 | 
#>  2 | {
#>  3 |   "a": 1,
#>  4 |   "b": [2, 3, 4],
#>  5 |   "[r]": {
#>  6 |     "this": "setting",
#>  7 |     // A comment!
#>  8 |     "that": true
#>  9 |   }
#> 10 | }

# Try to parse the JSON, but comments aren't allowed!
try(load_json(text = text, options = list(allow_comments = FALSE)))
#> Error in token_table(text = text, ranges = ranges, options = options) : 
#>   The JSON document contains comments, and this is not allowed. To allow comments, set the `allow_comments` option to `TRUE`.

# Extract parts of the JSON
load_json(text = text) |> select("b") |> unserialize_selected()
#> [[1]]
#> [[1]][[1]]
#> [1] 2
#> 
#> [[1]][[2]]
#> [1] 3
#> 
#> [[1]][[3]]
#> [1] 4
#> 
#> 
load_json(text = text) |> select("[r]") |> unserialize_selected()
#> [[1]]
#> [[1]]$this
#> [1] "setting"
#> 
#> [[1]]$that
#> [1] TRUE
#> 
#> 
load_json(text = text) |> select("[r]", "that") |> unserialize_selected()
#> [[1]]
#> [1] TRUE
#> 

# Use a `list()` combining strings and positional indices when
# arrays are involved
load_json(text = text) |> select("b", 2) |> unserialize_selected()
#> [[1]]
#> [1] 3
#>