flennic / advanced-r-programming-5

Repository for the course 732A94 Advanced Programming in R at Linköping University 2018. Assignment 5.

Advanced-r-programming-5

Repository for the course 732A94 Advanced Programming in R at Linköping University 2018. Assignment 5.

We are going to use the Kolada API. The format is perfect (JSON), the API has a documentation and follows the REST principle. The documentation can be found here.

A Tutorial how to consume a REST-API in R can be found here.

The packages needed are httr for the HTTP communication and jsonlite for mapping JSON data to data.frames.

Example for REST-Call

This is an example how the libraries can be used to fetch data. Be aware, that this example does not handle pagination.

library(httr)
library(jsonlite)

# Prepare Call
base = "http://api.kolada.se/"
endpoint = "v1/ou/data/peryear/N15030/2011"
webCall = paste(base, endpoint, sep="")

# Execution
response = GET(webCall)

# Deserialization
result = content(response, "text", encoding = "utf-8")
result.data.frame = as.data.frame(fromJSON(result, flatten = TRUE))

For this call, the response looks like this:

> head(result.data.frame)
  values.kpi    values.ou values.period values.value values.value_m values.value_f                                                                   next. count
1     N15030 V150114G0R01          2011         84.4             NA             NA http://api.kolada.se/v1/ou/data/peryear/N15030/2011?page=2&per_page=100   100
2     N15030 V150114G0R02          2011         81.8             NA             NA http://api.kolada.se/v1/ou/data/peryear/N15030/2011?page=2&per_page=100   100
3     N15030 V150115G0R01          2011         84.3             NA             NA http://api.kolada.se/v1/ou/data/peryear/N15030/2011?page=2&per_page=100   100
4     N15030 V150115G0R02          2011         62.1             NA             NA http://api.kolada.se/v1/ou/data/peryear/N15030/2011?page=2&per_page=100   100
5     N15030 V150117G0R01          2011         84.8             NA             NA http://api.kolada.se/v1/ou/data/peryear/N15030/2011?page=2&per_page=100   100
6     N15030 V150117G0R02          2011         76.4             NA             NA http://api.kolada.se/v1/ou/data/peryear/N15030/2011?page=2&per_page=100   100

Execution of the shiny- App

devtools::install_github("rubenjmunoz/advanced-r-programming-5", build_vignettes = TRUE)

library(shiny)
runGitHub('advanced-r-programming-5','rubenjmunoz')

devtools::use_vignette("advanced_r_5")