Accessing the Official 'Google Knowledge Graph' API.

gkgraphR

Easy access to the Google Knowledge Graph API (v1) from R. More information about the Google Knowledge Graph API can be found here: https://developers.google.com/knowledge-graph

Before starting

Please note that in order to access the API, users must register a Google account and create a project in the Google API console to obtain an API key. Using the Google Knowledge Graph API is free and a regular API account allows for up to 100.000 queries per day; additional API credits may be obtained through special request. More information on how to register an account and create a project can be found here: https://developers.google.com/knowledge-graph/prereqs

Installation

You can obtain the current development version from github:

# install.packages("devtools")
devtools::install_github("racorreia/gkgraphR", build_vignettes = T)

Querying the API

Querying the Google Knowledge Graph API through gkgraphR can be achieved through the function querygkg(). A simple query requires a valid Google API key and one of two elements: i) a search query, or ii) a Google Knowledge Graph entity ID. For example, a simple list of entities recognized by the Google Knowledge Graph API in relation to the term "apple" can be achieved with the following code:

# Load gkgraphR library
library(gkgraphR)

# Query the API for entities related to the term "apple"
query_apple <- querygkg(query = "apple", api.key = {YOUR_API_KEY}) # Replace YOUR_API_KEY with a valid Google API key

Similarly, querying the API for the entity "apple" representing the fruit or the entity "apple" representing the technology company can be achieved with the following queries:

# Query the API for the entity "apple" representing the fruit
query_apple_fruit <- querygkg(ids = "/m/014j1m", api.key = {YOUR_API_KEY}) # Replace YOUR_API_KEY with a valid Google API key

# Query the API for the entity "apple" representing the fruit
query_apple_company <- querygkg(ids = "/m/0k8z", api.key = {YOUR_API_KEY}) # Replace YOUR_API_KEY with a valid Google API key

More information on how to use package gkgraphR can be found in the package vignette:

vignette("gkgraphR")