Where is the crawled data stored when running nutch crawler?

nutch, web-crawler

Solution

After your crawl is over, you could use the bin/nutch dump command to dump all the urls fetched in plain html format.

The usage is as follows :

$ bin/nutch dump [-h] [-mimetype <mimetype>] [-outputDir <outputDir>]
   [-segment <segment>]
 -h,--help                show this help message
 -mimetype <mimetype>     an optional list of mimetypes to dump, excluding
                      all others. Defaults to all.
 -outputDir <outputDir>   output directory (which will be created) to host
                      the raw data
 -segment <segment>       the segment(s) to use

So for example you could do something like

$ bin/nutch dump -segment crawl/segments -outputDir crawl/dump/

This would create a new dir at the -outputDir location and dump all the pages crawled in html format.

There are many more ways of dumping out specific data from Nutch, have a look at https://wiki.apache.org/nutch/CommandLineOptions

Problem

I am new to Nutch. I need to crawl the web (say, a few hundred web pages), read the crawled data and do some analysis. I followed the link https://wiki.apache.org/nutch/NutchTutorial (and integrated Solr since I may require to search text in future) and ran the crawl using a few URLs as the seed. Now, I don't find the `text/html` data in my local machine. Where can I find the data and what is the best way to read the data in text format? Versions - apache-nutch-1.9 - solr-4.10.4

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