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httr (version 1.4.4)

POST: POST file to a server.

Description

POST file to a server.

Usage

POST(
  url = NULL,
  config = list(),
  ...,
  body = NULL,
  encode = c("multipart", "form", "json", "raw"),
  handle = NULL
)

Value

A response() object.

Arguments

url

the url of the page to retrieve

config

Additional configuration settings such as http authentication (authenticate()), additional headers (add_headers()), cookies (set_cookies()) etc. See config() for full details and list of helpers.

...

Further named parameters, such as query, path, etc, passed on to modify_url(). Unnamed parameters will be combined with config().

body

One of the following:

  • FALSE: No body. This is typically not used with POST, PUT, or PATCH, but can be useful if you need to send a bodyless request (like GET) with VERB().

  • NULL: An empty body

  • "": A length 0 body

  • upload_file("path/"): The contents of a file. The mime type will be guessed from the extension, or can be supplied explicitly as the second argument to upload_file()

  • A character or raw vector: sent as is in body. Use content_type() to tell the server what sort of data you are sending.

  • A named list: See details for encode.

encode

If the body is a named list, how should it be encoded? Can be one of form (application/x-www-form-urlencoded), multipart, (multipart/form-data), or json (application/json).

For "multipart", list elements can be strings or objects created by upload_file(). For "form", elements are coerced to strings and escaped, use I() to prevent double-escaping. For "json", parameters are automatically "unboxed" (i.e. length 1 vectors are converted to scalars). To preserve a length 1 vector as a vector, wrap in I(). For "raw", either a character or raw vector. You'll need to make sure to set the content_type() yourself.

handle

The handle to use with this request. If not supplied, will be retrieved and reused from the handle_pool() based on the scheme, hostname and port of the url. By default httr requests to the same scheme/host/port combo. This substantially reduces connection time, and ensures that cookies are maintained over multiple requests to the same host. See handle_pool() for more details.

See Also

Other http methods: BROWSE(), DELETE(), GET(), HEAD(), PATCH(), PUT(), VERB()

Examples

Run this code
b2 <- "http://httpbin.org/post"
POST(b2, body = "A simple text string")
POST(b2, body = list(x = "A simple text string"))
POST(b2, body = list(y = upload_file(system.file("CITATION"))))
POST(b2, body = list(x = "A simple text string"), encode = "json")

# body can also be provided as a json string directly to deal
# with specific case, like an empty element in the json string.
# passing as string directly
POST(b2, body = '{"a":1,"b":{}}', encode = "raw")
# or building the json string before
json_body <- jsonlite::toJSON(list(a = 1, b = NULL), auto_unbox = TRUE)
POST(b2, body = json_body, encode = "raw")

# Various types of empty body:
POST(b2, body = NULL, verbose())
POST(b2, body = FALSE, verbose())
POST(b2, body = "", verbose())

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