adding content_type_json() to a POST no longer works with v0.5

[wligtenberg]

I used to create a POST as follows:
POST(url = <URL>, body = <some json>, content_type_json())

However, using v0.5 this no longer works, however using:
POST(url = <URL>, body = <some json>, add_headers('Content-Type' = "application/json"))
Does work.

[hadley]

Could you please provide a reproducible example?

(Also you can now do POST(..., encode = "json"))

[wligtenberg]

Unfortunately, the API I am programming against is not publicly available.
I will have a look at the encode = "json", and report back if that resolves my issues.

[wligtenberg]

unfortunately, I also cannot use the encode = "json" version, because that generates the wrong JSON.
It does set the Content-type correctly to application/json.
However, it creates arrays for every item in the list, which RJSONIO does not.
E.g.
RJSONIO generates:
{"properties":{"id":"id2","name":"MyName","age":"20"}}
encode = "json" generates:
{"properties":{"id":["id2"],"name":["MyName"],"age":["20"]}}
This then results in a bad request.

[hadley]

Yeah, you'd have to use unbox(). But I don't understand why content_type_json() doesn't work for you:

The output is identical for me:

> httr::content_type_json()
Config: 
List of 1
 $ httpheader:"application/json"
  ..- attr(*, "names")="Content-type"
> httr::add_headers('Content-Type' = "application/json")
Config: 
List of 1
 $ httpheader:"application/json"
  ..- attr(*, "names")="Content-Type"

(modulo case, which doesn't matter, and hasn't changed in 0.5)

[wligtenberg]

The output is the same for me as well, however, when I use it in POST it does not behave the same.

If I put unbox() around all the things nested in the list, it works.
However, it is a lot easier for me, to just use RJSONIO for the JSON conversion and then use: add_headers('Content-Type' = "application/json") for now.

[wligtenberg]

Hi Hadley,

I think I have found the problem. I will see if I can fix it myself.
But that might be tomorrow.
If the body is a character (which is in my case) the body_raw function is called as follows:

if (is.character(body) || is.raw(body)) {
  return(body_raw(body))
}

which results in "Content-type" being set to "", because type is NULL.

[hadley]

Oh hmmm, so the reason that content_type_json() doesn't work is actually a bug in how headers are overrdien.