kernel_api: REDCapR internal function for calling the REDCap API

Description

This function is used by other functions to read and write values.

Usage

kernel_api(
  redcap_uri,
  post_body,
  config_options,
  encoding = "UTF-8",
  content_type = "text/csv",
  handle_httr = NULL,
  encode_httr = "form"
)

Value

A utils::packageVersion.

Arguments

redcap_uri: The uri/url of the REDCap server typically formatted as "https://server.org/apps/redcap/api/". Required.
post_body: List of contents expected by the REDCap API. Required.
config_options: A list of options passed to httr::POST(). See details at httr::httr_options(). Optional.
encoding: The encoding value passed to httr::content(). Defaults to 'UTF-8'.
content_type: The MIME value passed to httr::content(). Defaults to 'text/csv'.
handle_httr: The value passed to the handle parameter of httr::POST(). This is useful for only unconventional authentication approaches. It should be NULL for most institutions.
encode_httr: The value passed to the encode parameter of httr::POST(). Defaults to "form", which is appropriate for most actions. (Currently, the only exception is importing a file, which uses "multipart".)

Details

If the API call is unsuccessful, a value of base::package_version("0.0.0") will be returned. This ensures that a the function will always return an object of class base::package_version. It guarantees the value can always be used in utils::compareVersion().

Examples

Run this code

config_options <- NULL
uri            <- "https://redcap-dev-2.ouhsc.edu/redcap/api/"
token          <- "9A068C425B1341D69E83064A2D273A70"
post_body      <- list(
  token    = token,
  content  = "project",
  format   = "csv"
)
if (FALSE) {
kernel <- REDCapR:::kernel_api(uri, post_body, config_options)

# Consume the results in a few different ways.
kernel$result
read.csv(text = kernel$raw_text)
as.list(read.csv(text = kernel$raw_text))
}