Attempts to load an R object from a URL using `load()`, with automatic retries on failure. By default, it will retry indefinitely until successful.
Arguments
- url
A character string specifying the URL from which to load the `.RData` object.
- max_attempts
The maximum number of attempts before giving up. If `NULL` (the default), the function will retry indefinitely until successful.
- delay
The number of seconds to wait between attempts (default = 2).
- envir
The environment into which the data should be loaded (default is the global environment).
- ...
Parameters to pass to the `load()` function
Value
Invisibly returns `TRUE` if loading succeeds. On failure after reaching the maximum number of attempts, an error is thrown.
Details
This function wraps a call to `load(url(...))` in a retry loop. It is useful when loading data from unstable remote sources (e.g., OSF, Dropbox, GitHub) where temporary network errors may occur. Users may optionally set a maximum number of retry attempts and a delay between retries. The function also closes the connection after each attempt to prevent resource leaks.
Examples
# Example of a successful load (will do nothing if URL is valid)
# \donttest{
robust_load("https://osf.io/download/yx5h6/")
# Example with limited retries
robust_load("https://osf.io/download/yx5h6/", max_attempts = 4, delay = 1)
# Example of a failing load, wrapped safely to pass R CMD check
try(
robust_load("https://osf.io/download/THISISATEST/", max_attempts = 3, delay = 1),
silent = TRUE
)
#> Warning: cannot open URL 'https://osf.io/download/THISISATEST/': HTTP status was '404 Not Found'
#> Attempt 1 failed: cannot open the connection to 'https://osf.io/download/THISISATEST/'
#> Warning: cannot open URL 'https://osf.io/download/THISISATEST/': HTTP status was '404 Not Found'
#> Attempt 2 failed: cannot open the connection to 'https://osf.io/download/THISISATEST/'
#> Warning: cannot open URL 'https://osf.io/download/THISISATEST/': HTTP status was '404 Not Found'
#> Attempt 3 failed: cannot open the connection to 'https://osf.io/download/THISISATEST/'
# }
