How do I convert a data table to this JSON object format in R?

I'm attempting to use this Qualtrics API endpoint (https://api.qualtrics.com/0cc0b9dcffc6f-start-a-delete-survey-responses-job) with R to bulk-remove responses from a survey by using httr and jsonlite R packages. It is important to leave the data input as-is because the script should let someone copy/paste in a series of response id’s directly from an Excel doc.

Here is my current code with dummy data (everything except for the post request code):

install.packages(c("httr", "jsonlite"))
library(httr)
library(jsonlite)

data <- read.table(text='
R_010101010101010
R_010101010101010
R_010101010101010
R_010101010101010
R_010101010101010
')
colnames(data) <- 'responseId'

allResponses <- list()
for (row in 1:nrow(data)) {
  response <- list(responseId=data[row, 1],decrementQuotas=TRUE)
  allResponses <- append(allResponses, response)
}

postData <- toJSON(list(deletes=allResponses))
print(postData)

I’m getting an error when trying to submit the POST request because the body of the request is not the right format. It needs to be in this format:

{
  "deletes": [
    {
      "responseId": "R_1234",
      "decrementQuotas": true
    }
  ]
}

But what my code prints is this

{"deletes":{"responseId":["R_010101010101010"],"decrementQuotas":[true],"responseId.1":["R_010101010101010"],"decrementQuotas.1":[true],"responseId.2":["R_010101010101010"],"decrementQuotas.2":[true],"responseId.3":["R_010101010101010"],"decrementQuotas.3":[true],"responseId.4":["R_010101010101010"],"decrementQuotas.4":[true]}}

Can you all help me coerce this data into the correct JSON format?

Solution

Be careful with append. Right now it's not building the list the way you want. You would do the loop more like

allResponses <- list()
for (row in 1:nrow(data)) {
  response <- list(responseId=data[row, 1],decrementQuotas=TRUE)
  allResponses <- append(allResponses, list(response))
}

postData <- toJSON(list(deletes=allResponses), auto_unbox = TRUE)
cat(postData)
# {"deletes":[{"responseId":"R_010101010101010","decrementQuotas":true},
# {"responseId":"R_010101010101010","decrementQuotas":true},
# {"responseId":"R_010101010101010","decrementQuotas":true},
# {"responseId":"R_010101010101010","decrementQuotas":true},
# {"responseId":"R_010101010101010","decrementQuotas":true}]}

Here we also use auto_unbox to remove the extra brackets

But rather than usign the loop, a better way to make the list would be to use something like lapply in the first place

allResponses <- lapply(1:nrow(data), function(row) {
  list(responseId=data[row, 1],decrementQuotas=TRUE)
})

No need for the loop and append in this case.