try_query {protti}

Query from URL

Description

Downloads data table from URL. If an error occurs during the query (for example due to no connection) the function waits 3 seconds and tries again. If no result could be obtained after the given number of tries a message indicating the problem is returned.

Usage

try_query(
  url,
  max_tries = 5,
  silent = TRUE,
  type = "text/tab-separated-values",
  timeout = 60,
  accept = NULL,
  ...
)

Arguments

url

a character value of an URL to the website that contains the table that should be downloaded.

max_tries

a numeric value that specifies the number of times the function tries to download the data in case an error occurs. Default is 5.

silent

a logical value that specifies if individual messages are printed after each try that failed.

type

a character value that specifies the type of data at the target URL. Options are all options that can be supplied to httr::content, these include e.g. "text/tab-separated-values", "application/json" and "txt/csv". Default is "text/tab-separated-values". Default is "tab-separated-values".

timeout

a numeric value that specifies the maximum request time. Default is 60 seconds.

accept

a character value that specifies the type of data that should be sent by the API if it uses content negotiation. The default is NULL and it should only be set for APIs that use content negotiation.

...

other parameters supplied to the parsing function used by httr::content.

Value

A data frame that contains the table from the url.