This builds upon PR #28 to make use of custom exceptions module.
Implements begin -> rescue -> retry loop:
An attempt is made to open the challenge URL.
If the url is unavailable, the error is rescued and another attempt is made every 5 secs for a maximum of 30 secs. This should be sufficient to allow config variables to update etc.
If this time limit is reached, a custom error is raised.
This builds upon PR #28 to make use of custom exceptions module. Implements begin -> rescue -> retry loop:
Addresses issue #9.