607 Assignment 10 - Web APIs

---

Assignment overview: Download JSON data provided through New York Times Web API portal into R data frame.

Data of choice: New York Times Best Sellers Books

Step 1: Load required libraries

library(jsonlite)
library(dplyr)
library(knitr)

Step 2: Create wrapper function getBestSeller

#Get books ranked 1st for the type provided in the argument
  getBestSeller <- function(uri, format=".json", list_type, rank=1,api_key){
      json_output    <- fromJSON(paste(uri, format,
                                 "?list-name=", list_type,
                                 "&rank=", rank,
                                 "&api-key=", api_key, 
                                 sep=""))
      results       <- json_output$results
      # book_detail contains list so convert it to data frame and then bind it to results
      details       <- as.data.frame(results$book_detail)
      final_output  <- cbind(results, details) %>% select(list_name, rank,title, author, description)
    
      return(final_output)
}

Step 3: Get most recent Best Sellers

Store api-key and base url into variables

nyt_api_key <- "543adc61e14cf137f5a2121ec35d7d35:4:73310298"
nyt_uri <- "http://api.nytimes.com/svc/books/v3/lists"

Call getBestSeller one at a time

# get hardcover-fiction
kable(getBestSeller(uri = nyt_uri,list_type = "hardcover-fiction", api_key = nyt_api_key))

list_name	rank	title	author	description
Hardcover Fiction	1	ROGUE LAWYER	John Grisham	The attorney Sebastian Rudd is a “lone gunman” who hates injustice and the system and defends unpopular clients.

# e-book-fiction
kable(getBestSeller(uri = nyt_uri,list_type = "e-book-fiction", api_key = nyt_api_key))

list_name	rank	title	author	description
E-Book Fiction	1	ROGUE LAWYER	John Grisham	The attorney Sebastian Rudd is a “lone gunman” who hates injustice and the system and defends unpopular clients.

Or create a vector of items and then call the function

list_names <- c("hardcover-fiction","e-book-fiction","trade-fiction-paperback", "hardcover-nonfiction")
best_sellers <- lapply(list_names, function(x) getBestSeller(uri = nyt_uri,list_type = x, api_key = nyt_api_key))
best_sellers_df <- dplyr::rbind_all(best_sellers)
kable(best_sellers_df)

list_name	rank	title	author	description
Hardcover Fiction	1	ROGUE LAWYER	John Grisham	The attorney Sebastian Rudd is a “lone gunman” who hates injustice and the system and defends unpopular clients.
E-Book Fiction	1	ROGUE LAWYER	John Grisham	The attorney Sebastian Rudd is a “lone gunman” who hates injustice and the system and defends unpopular clients.
Trade Fiction Paperback	1	THE MARTIAN	Andy Weir	After a dust storm forces his crew to abandon him, an astronaut embarks on a dogged quest to stay alive on Mars.
Hardcover Nonfiction	1	KILLING REAGAN	Bill O’Reilly and Martin Dugard	The host of “The O’Reilly Factor” recounts the events surrounding the attempted assassination of President Reagan in 1981.

---

---