makeFunction: Generate R code to interface to a WADL method

In duncantl/WADL: Programmatically process Web Application Description Language documents

Generate R code to interface to a WADL method

Description

This function is the work-horse that generates the R code for a function with which we can interface to a REST method described by a WADL resource/method. This is repsonsible for creating the signature of the function, including the default values, and the body that invokes the method.

Usage

makeFunction(params, url, options = params$options, name = "foo", converter = "NULL",
             action = "getForm",
             OptionsCharacterThreshold = getOption("WADLOptionsCharacterThreshold", 5000L),
             hooks = list(makeSignature = makeSignature, preCall = NULL, postCall = NULL))

Arguments

params	a description of the WADL method. This is a data frame with as many rows as there are parmeters in the WADL method. The columns are name, type, required, default and repeating. This gives us all the information about each of the parameters
url	the URL for this method's resource
options	a list with information about each parameter
name	the name of the R function to be created
converter	an optional expression or symbol name that identifies the default converter, if any, that can process the result of the REST invocation and turn it into a more meaningful R object.
action	the name of the R function (in RCurl) to call when making the REST request. This is typically either "getForm" or "postForm".
OptionsCharacterThreshold	an integer value that controls how big the size of the permissible values vector for a parameter must be before we make it a global variable. This is to avoid issues with functions being too long to read and maintain the source as text as an attribute.
hooks	a list with elements for any of the makeSignature, preCall and postCall. Each of these is a function that is called during the construction of the code for the R function to call the Web Service method. The preCall and postCall functions are passed a data frame describing the parameters, the URL of the method and the name of the method. The makeSignature function is called with the names of the parameters, the default values, a character vector of the additional arguments and their default values, the name of the method and the URL. The additional arguments are given as a named character vector with the names giving the parameter names and the values giving the default value. ... is special and has no name.

Value

If eval is TRUE or an environment, we define the function in that environment (or globalenv. If eval is FALSE, we return the text (character vector) containing the R code.

Author(s)

Duncan Temple Lang

duncantl/WADL documentation built on Nov. 23, 2023, 4:28 p.m.