Summary

Now you know how to make calls! The general template for making a call (after making sure authentication is set up) is as follows.

1. Determine an endpoint for your service (possibly with the services object).

endpoint <- 'APIEndpoint'

2. Make the call with perform.call().

result <- perform.call(endpoint)

3. If the call requires a single variable, declare the variable with the API variable name and pass it in as a second argument in perform.call().

variable <- "value"
result <- perform.call(endpoint, variable)

Or, specify the name of the API variable in the third argument.

variable.code <- "value"
result <- perform.call(endpoint, variable.code, name = "API variable name")

4. If the call requires multiple variables, make a list and pass it in as a second argument in perform.call().

variables <- list(variable.one = "value.one",
                  variable.two = "value.two",
                  variable.three = "value.three")
result <- perform.call(endpoint, variables)

Or, specify the names of parameter codes in the second argument.

variables <- list("value.one", "value.two", "value.three")
result <- perform.call(endpoint, 
                       variables,
                       name = list("variable.one", "variable.two", "variable.three"))