[jira] [Commented] (NUTCH-1422) reset signature for redirects

["Julien Nioche (JIRA)" <ji...@apache.org>]

    [ https://issues.apache.org/jira/browse/NUTCH-1422?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13982844#comment-13982844 ] 

Julien Nioche commented on NUTCH-1422:
--------------------------------------

The redirection can be done via HTML instructions and discovered when parsing so sorting this in CrawlDbReducer.reduce would probably be cleaner.

> reset signature for redirects
> -----------------------------
>
>                 Key: NUTCH-1422
>                 URL: https://issues.apache.org/jira/browse/NUTCH-1422
>             Project: Nutch
>          Issue Type: Bug
>          Components: crawldb, fetcher
>    Affects Versions: 1.4
>            Reporter: Sebastian Nagel
>            Priority: Critical
>             Fix For: 1.9
>
>         Attachments: NUTCH-1422_redir_notmodified_log.txt
>
>
> In a long running continuous crawl with Nutch 1.4 URLs with a HTTP redirect (http.redirect.max = 0) are kept as not-modified in the CrawlDb. Short protocol (cf. attached dumped segment / CrawlDb data):
>  2012-02-23 :  injected
>  2012-02-24 :  fetched
>  2012-03-30 :  re-fetched, signature changed
>  2012-04-20 :  re-fetched, redirected
>  2012-04-24 :  in CrawlDb as db_notmodified, still indexed with old content!
> The signature of a previously fetched document is not reset when the URL/doc is changed to a redirect at a later time. CrawlDbReducer.reduce then sets the status to db_notmodified because the new signature in with fetch status is identical to the old one.
> Possible fixes (??):
> * reset the signature in Fetcher
> * handle this case in CrawlDbReducer.reduce



--
This message was sent by Atlassian JIRA
(v6.2#6252)