source_data: Load plain-text data and RData from a URL (either http or...
In repmis: Miscellaneous Tools for Reproducible Research

Description Usage Arguments Details Value Source See Also Examples

View source: R/source_data.R

source_data loads plain-text or RDATA formatted data stored at a URL (both http and https) into R.

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source_data(url, rdata, sha1 = NULL, cache = FALSE, clearCache = FALSE,
  sep = "auto", header = "auto", stringsAsFactors = FALSE,
  envir = parent.frame(), ...)

`url`	The data's URL. To distinguish between plain-text and RDATA the `url` must end in a distinguishing file extension.
`rdata`	logical. Whether or not the data set is an `.RDATA` file. If not specified than `source_url` will attempt to determine whether or not the file is an `.RDATA` file from the URL's extension.
`sha1`	Character string of the file's SHA-1 hash, generated by `source_data`. Note if you are using data stored using Git, this is not the file's commit SHA-1 hash.
`cache`	logical. Whether or not to cache the data so that it is not downloaded every time the function is called.
`clearCache`	logical. Whether or not to clear the downloaded data from the cache.
`sep`	The separator method for the plain-text data. For example, to load comma-separated values data (CSV) use `sep = ","`. To load tab-separated values data (TSV) use `sep = "\t"`. Only relevant for plain-text data.
`header`	Logical, whether or not the first line of the file is the header (i.e. variable names).
`stringsAsFactors`	logical. Convert all character columns to factors?
`envir`	the environment where the data should be loaded.
`...`	additional arguments passed to `fread` or `load` as relevant.

Loads plain-text data (e.g. CSV, TSV) or RDATA from a URL. Works with both HTTP and HTTPS sites. Note: the URL you give for the url argument must be for the RAW version of the file. The function should work to download plain-text data from any secure URL (https), though I have not verified this.

From the source_url documentation: "If a SHA-1 hash is specified with the sha1 argument, then this function will check the SHA-1 hash of the downloaded file to make sure it matches the expected value, and throw an error if it does not match. If the SHA-1 hash is not specified, it will print a message displaying the hash of the downloaded file. The purpose of this is to improve security when running remotely-hosted code; if you have a hash of the file, you can be sure that it has not changed."

a data frame

Originally based on source_url from the Hadley Wickham's devtools package.

httr, fread, and load

## Not run: 
# Download electoral disproportionality data stored on GitHub
# Note: Using shortened URL created by bitly
DisData <- source_data("http://bit.ly/156oQ7a")

# Check to see if SHA-1 hash matches downloaded file
DisDataHash <- source_data("http://bit.ly/Ss6zDO",
   sha1 = "dc8110d6dff32f682bd2f2fdbacb89e37b94f95d")

## End(Not run)