When the Fetcher tries to access an URI and gets status 500/503 is returned, the URI is removed when the response (empty list of triples) is sent to the Frontier.
The Fetcher should implement the Retry Pattern. A parameter should be passed to the frontier to determine
how many retries should execute and the waiting time between retries. If still, a flag should be put in Crawleable URI data map, so the queue won't delete this URI and may crawl it later.
When the Fetcher tries to access an URI and gets status 500/503 is returned, the URI is removed when the response (empty list of triples) is sent to the Frontier. The Fetcher should implement the Retry Pattern. A parameter should be passed to the frontier to determine how many retries should execute and the waiting time between retries. If still, a flag should be put in Crawleable URI data map, so the queue won't delete this URI and may crawl it later.