Question 214174 in Json Question posted in
Our archive of expertly curated questions and answers provides insights and solutions to common problems related to this popular data interchange format. From parsing and manipulating JSON data to integrating it with various programming languages and web services, our archive has got you covered. Start exploring today and take your JSON skills to the next level

Convert JavaScript array of objects to JSON in r programming language

I need to pass JSON object to a function in r programming. The following are the various examples of JavaScript objects that can be passed which needed to be converted to JSON in r

Example1 = [
  {name: "Orange", data: {"Tuesday": 3, "Friday": 4}, stack: "fruit"},
  {name: "Apple", data: {"Tuesday": 1, "Friday": 8}, stack: "fruit"},
  {name: "Cucumber", data: {"Tuesday": 3, "Friday": 4}, stack: "vegetable"},
  {name: "Carrot", data: {"Tuesday": 1, "Friday": 8}, stack: "vegetable"}
]

Example2 = [["Washington", "1789-04-29", "1797-03-03"], ["Adams", "1797-03-03", "1801-03-03"]]

I need help converting them into a JSON object in r using jsonlite package.

Tags:

2

Answers


  1. Chosen as BEST ANSWER
    0

    Thank you @margusl I just resolved Example1

    jsonlite::toJSON('[
  {name: "Orange", data: {"Tuesday": 3, "Friday": 4}, stack: "fruit"},
  {name: "Apple", data: {"Tuesday": 1, "Friday": 8}, stack: "fruit"},
  {name: "Cucumber", data: {"Tuesday": 3, "Friday": 4}, stack: "vegetable"},
  {name: "Carrot", data: {"Tuesday": 1, "Friday": 8}, stack: "vegetable"}
]')

    But, this is not actually what I want. I wish I could achieve the same output as what I would get in JavaScript when I use JSON.stringify() where the keys are quoted. I hope I could get help here


  2. 0

    Javascript code can be evaluated with v8, that code can include JSON.stringify(), but for a list of simple assignment expressions we can set serialize parameter for $eval() method and it will return JSON string:

    library(V8)
#> Using V8 engine 9.1.269.38
js <- c(
  ex1 = 'Example1 = [
  {name: "Orange", data: {"Tuesday": 3, "Friday": 4}, stack: "fruit"},
  {name: "Apple", data: {"Tuesday": 1, "Friday": 8}, stack: "fruit"},
  {name: "Cucumber", data: {"Tuesday": 3, "Friday": 4}, stack: "vegetable"},
  {name: "Carrot", data: {"Tuesday": 1, "Friday": 8}, stack: "vegetable"}
]',
  ex2 = 'Example2 = [["Washington", "1789-04-29", "1797-03-03"], ["Adams", "1797-03-03", "1801-03-03"]]'
)

ctx <- v8()
# evaluate and serialize js return object
json_1 <- ctx$eval(js[1], serialize = TRUE) 
jsonlite::validate(json_1)
#> [1] TRUE
json_1
#> [1] "[{"name":"Orange","data":{"Tuesday":3,"Friday":4},"stack":"fruit"},{"name":"Apple","data":{"Tuesday":1,"Friday":8},"stack":"fruit"},{"name":"Cucumber","data":{"Tuesday":3,"Friday":4},"stack":"vegetable"},{"name":"Carrot","data":{"Tuesday":1,"Friday":8},"stack":"vegetable"}]"

# or apply ctx$eval() on the the list of expressions
json_lst <- lapply(js, ctx$eval, serialize = TRUE)
str(json_lst)
#> List of 2
#>  $ ex1: chr "[{"name":"Orange","data":{"Tuesday":3,"Friday":4},"stack":"fruit"},{"name":"Apple","data":{"| __truncated__
#>  $ ex2: chr "[["Washington","1789-04-29","1797-03-03"],["Adams","1797-03-03","1801-03-03"]]"

    Created on 2023-07-23 with reprex v2.0.2

    Login or Signup to reply.
Please signup or login to give your own answer.

Back To Top
Search