downloadRemote: Download a remote file
In reproducible: Enhance Reproducibility of R Code

downloadRemote

R Documentation

Download a remote file

Description

Download a remote file

Usage

downloadRemote(
  url,
  archive,
  targetFile,
  checkSums,
  dlFun = NULL,
  fileToDownload,
  messSkipDownload,
  destinationPath,
  overwrite,
  needChecksums,
  .tempPath,
  preDigest,
  verbose = getOption("reproducible.verbose", 1),
  ...
)

Arguments

`url`	Optional character string indicating the URL to download from. If not specified, then no download will be attempted. If not entry exists in the `CHECKSUMS.txt` (in `destinationPath`), an entry will be created or appended to. This `CHECKSUMS.txt` entry will be used in subsequent calls to `prepInputs` or `preProcess`, comparing the file on hand with the ad hoc `CHECKSUMS.txt`. See table in `preProcess()`.
`archive`	Optional character string giving the path of an archive containing `targetFile`, or a vector giving a set of nested archives (e.g., `c("xxx.tar", "inner.zip", "inner.rar")`). If there is/are (an) inner archive(s), but they are unknown, the function will try all until it finds the `targetFile`. See table in `preProcess()`. If it is `NA`, then it will not attempt to see it as an archive, even if it has archive-like file extension (e.g., `.zip`). This may be useful when an R function is expecting an archive directly.
`targetFile`	Character string giving the filename (without relative or absolute path) to the eventual file (raster, shapefile, csv, etc.) after downloading and extracting from a zip or tar archive. This is the file before it is passed to `postProcess`. The internal checksumming does not checksum the file after it is `postProcess`ed (e.g., cropped/reprojected/masked). Using `Cache` around `prepInputs` will do a sufficient job in these cases. See table in `preProcess()`.
`checkSums`	TODO
`dlFun`	Optional "download function" name, such as `"raster::getData"`, which does custom downloading, in addition to loading into R. Still experimental.
`fileToDownload`	TODO
`messSkipDownload`	The character string text to pass to messaging if download skipped
`destinationPath`	Character string of a directory in which to download and save the file that comes from `url` and is also where the function will look for `archive` or `targetFile`. NOTE (still experimental): To prevent repeated downloads in different locations, the user can also set `options("reproducible.inputPaths")` to one or more local file paths to search for the file before attempting to download. Default for that option is `NULL` meaning do not search locally.
`overwrite`	Logical. Should downloading and all the other actions occur even if they pass the checksums or the files are all there.
`needChecksums`	Logical indicating whether to generate checksums. ## TODO: add overwrite arg to the function?
`.tempPath`	Optional temporary path for internal file intermediate steps. Will be cleared on.exit from this function.
`preDigest`	The list of `preDigest` that comes from `CacheDigest` of an object
`verbose`	Numeric, -1 silent (where possible), 0 being very quiet, 1 showing more messaging, 2 being more messaging, etc. Default is 1. Above 3 will output much more information about the internals of Caching, which may help diagnose Caching challenges. Can set globally with an option, e.g., `⁠options('reproducible.verbose' = 0) to reduce to minimal⁠`
`...`	Additional arguments passed to `postProcess()` and `Cache()`. Since `...` is passed to `postProcess()`, these will `...` will also be passed into the inner functions, e.g., `cropInputs()`. Possibly useful other arguments include `dlFun` which is passed to `preProcess`. See details and examples.