Per-element control of `unbox`

[mmuurr]

{jsonify} is great, but I struggle to use it as a mediator for communication with some external APIs due to one missing feature: element-level control of the unbox parameter (in to_json()).
A third-party API might expect this object:

{
  "unboxed_prop": "foo",
  "boxed_prop": ["variable", "length", "array"]
}

With {jsonlite}, we'd coerce the corresponding R object to something like:

x <- some_data_here()  ## may return a vector of length 0, 1, or more
list(
  unboxed_prop = "foo",
  boxed_prop = I(x)  ## 'protect' the value here with I()/AsIs
) |>
jsonlite::toJSON(auto_unbox = TRUE)

With I(x), boxed_prop is guaranteed to be JSON-encoded as an array regardless of length(x).

Is something like this possible with {jsonify}?

[dcooley]

These give the same output

x <- 1:3
l <- list(
  unboxed_prop = "foo",
  boxed_prop = I(x)  ## 'protect' the value here with I()/AsIs
)

l |> jsonlite::toJSON(auto_unbox = TRUE)
l |> jsonify::to_json(unbox = TRUE)

so I'm not really sure what your question is

[mmuurr]

When length(x) == 1, they yield different outputs:

x <- 1
l <- list(
  unboxed_prop = "foo",
  boxed_prop = I(x)  ## 'protect' the value here with I()/AsIs
)

l |> jsonlite::toJSON(auto_unbox = TRUE)  ## {"unboxed_prop":"foo","boxed_prop":[1]}
l |> jsonify::to_json(unbox = TRUE)  ## {"unboxed_prop":"foo","boxed_prop":1.0}

And here the key is that a receiver of this JSON may require that "boxed_prop" be an array, while also requiring the "unboxed_prop" is scalar.

[dcooley]

There's a working prototype on branch issue75 if you want to try it:

remotes::install_github("SymbolixAU/jsonify", ref = "issue75")

[mmuurr]

Thanks! I'll take a look over the next day or so and report back :-)

[dcooley]

Hi @mmuurr did this work for you?

[OlaCaster]

+1 on this request; jsonlite::unbox offers great flexibility and, as mentioned above, explicit control of unboxing may be required by the recipient

[dcooley]

This is working on branch issue75. I was waiting for the OP to test to see if it worked for them. Perhaps you could try it @OlaCaster and let me know if this works for your needs?

Install the issue75 branch with:

remotes::install_github("SymbolixAU/jsonify", ref = "issue75")

Then this should work

x <- 1
l <- list(
  unboxed_prop = "foo",
  boxed_prop = I(x)  ## 'protect' the value here with I()/AsIs
)

l |> jsonlite::toJSON(auto_unbox = TRUE)
# {"unboxed_prop":"foo","boxed_prop":[1]} 
l |> jsonify::to_json(unbox = TRUE)
# {"unboxed_prop":"foo","boxed_prop":[1.0]} 

[dcooley]

Note, however, using I() also prevents any length vectors being unboxed

x <- 1
l <- list(
  unboxed_prop = "foo",
  boxed_prop = I(c(x,x))  ## length > 1 vector
)

l |> jsonlite::toJSON(auto_unbox = TRUE)
# {"unboxed_prop":"foo","boxed_prop":[1,1]} 
l |> jsonify::to_json(unbox = TRUE)
# {"unboxed_prop":"foo","boxed_prop":[1.0,1.0]}