HTTP? httr! (2)

Web content does not limit itself to HTML pages and files stored on remote servers such as DataCamp's Amazon S3 instances. There are many other data formats out there. A very common one is JSON. This format is very often used by so-called Web APIs, interfaces to web servers with which you as a client can communicate to get or store information in more complicated ways.

You'll learn about Web APIs and JSON in the video and exercises that follow, but some experimentation never hurts, does it?

This exercise is part of the course

Intermediate Importing Data in R

Exercise instructions

Use GET() to get the url that has already been specified in the sample code. Store the response as resp.
Print resp. What is the content-type?
Use content() to get the content of resp. Set the as argument to "text". Simply print out the result. What do you see?
Use content() to get the content of resp, but this time do not specify a second argument. R figures out automatically that you're dealing with a JSON, and converts the JSON to a named R list.

Hands-on interactive exercise

Have a go at this exercise by completing this sample code.

# httr is already loaded

# Get the url
url <- "http://www.omdbapi.com/?apikey=72bc447a&t=Annie+Hall&y=&plot=short&r=json"


# Print resp


# Print content of resp as text


# Print content of resp

Edit and Run Code

This exercise is part of the course

Intermediate Importing Data in R

IntermediateSkill Level

4.8+

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Exercise 1: SQL Queries from inside R Exercise 2: Query tweater (1)Exercise 3: Query tweater (2)Exercise 4: Query tweater (3)Exercise 5: Query tweater (4)Exercise 6: Join the query madness!Exercise 7: DBI internals Exercise 8: Send - Fetch - Clear Exercise 9: Be polite and ...

More and more of the information that data scientists are using resides on the web. Importing this data into R requires an understanding of the protocols used on the web. In this chapter, you'll get a crash course in HTTP and learn to perform your own HTTP requests from inside R.

Exercise 1: HTTP Exercise 2: Import flat files from the web Exercise 3: Secure importing Exercise 4: Downloading files Exercise 5: Import Excel files from the web Exercise 6: Downloading any file, secure or not Exercise 7: Reading a text file from the web Exercise 8: HTTP? httr! (1)Exercise 9: HTTP? httr! (2)

Current Exercise

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Exercise 1: APIs & JSON Exercise 2: From JSON to R Exercise 3: Import JSON data from API Exercise 4: OMDb API Exercise 5: JSON & jsonlite Exercise 6: JSON practice (1)Exercise 7: JSON practice (2)Exercise 8: toJSON()Exercise 9: Minify and prettify

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