Styjun

I'm trying to use Nutch Fetcher to fetch the entire website, but it only loads the first URL:

import org.apache.nutch.fetcher.Fetcher;
new Fetcher(conf).fetch(segment, 1);

This is what I see in the log:

[INFO] org.apache.nutch.fetcher.Fetcher: Fetcher: starting at 2019-03-29 00:11:47
[INFO] org.apache.nutch.fetcher.Fetcher: Fetcher: segment: /var/folders/vl/633jwjvn2jvbj9zfg1sgglhw0000gp/T/1198814103175176756/segments/20190329001146
[WARN] org.apache.hadoop.mapreduce.JobResourceUploader: Hadoop command-line option parsing not performed. Implement the Tool interface and execute your application with ToolRunner to remedy this.
[INFO] org.apache.nutch.fetcher.FetchItemQueues: Using queue mode : byHost
[INFO] org.apache.nutch.fetcher.Fetcher: Fetcher: threads: 1
[INFO] org.apache.nutch.fetcher.Fetcher: Fetcher: time-out divisor: 2
[INFO] org.apache.nutch.fetcher.QueueFeeder: QueueFeeder finished: total 1 records hit by time limit : 0
[INFO] org.apache.nutch.net.URLExemptionFilters: Found 0 extensions at point:'org.apache.nutch.net.URLExemptionFilter'
[INFO] org.apache.nutch.fetcher.FetcherThread: FetcherThread 129 Using queue mode : byHost
[INFO] org.apache.nutch.fetcher.Fetcher: Fetcher: throughput threshold: -1
[INFO] org.apache.nutch.fetcher.Fetcher: Fetcher: throughput threshold retries: 5
[INFO] org.apache.nutch.fetcher.FetcherThread: FetcherThread 133 fetching http://www.zerocracy.com/ (queue crawl delay=5000ms)
[INFO] org.apache.nutch.protocol.RobotRulesParser: robots.txt whitelist not configured.
[INFO] org.apache.nutch.protocol.http.Http: http.proxy.host = null
[INFO] org.apache.nutch.protocol.http.Http: http.proxy.port = 8080
[INFO] org.apache.nutch.protocol.http.Http: http.proxy.exception.list = false
[INFO] org.apache.nutch.protocol.http.Http: http.timeout = 10000
[INFO] org.apache.nutch.protocol.http.Http: http.content.limit = 65536
[INFO] org.apache.nutch.protocol.http.Http: http.agent = yc/Nutch-1.15
[INFO] org.apache.nutch.protocol.http.Http: http.accept.language = en-us,en-gb,en;q=0.7,*;q=0.3
[INFO] org.apache.nutch.protocol.http.Http: http.accept = text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8
[INFO] org.apache.nutch.protocol.http.Http: http.enable.cookie.header = true
[INFO] org.apache.nutch.fetcher.FetcherThread: FetcherThread 133 has no more work available
[INFO] org.apache.nutch.fetcher.FetcherThread: FetcherThread 133 -finishing thread FetcherThread, activeThreads=0
[INFO] org.apache.nutch.fetcher.Fetcher: -activeThreads=0, spinWaiting=0, fetchQueues.totalSize=0, fetchQueues.getQueueCount=0
[INFO] org.apache.nutch.fetcher.Fetcher: -activeThreads=0
[INFO] org.apache.nutch.fetcher.Fetcher: Fetcher: finished at 2019-03-29 00:11:49, elapsed: 00:00:02

What am I missing? It's Nutch 1.15.

The Fetcher class is only responsible of fetching/downloading the URLs present in the segment, using a configured number of threads. This translates into the fetcher not parsing or extracting URLs out of the fetched content. The fetch method only downloads the content, nothing more. For your use case you would need to parse the HTML content by your self (or using the org/apache/nutch/parse tools) and generate a new segment for fetching the newly discovered links.

This is how usually Nutch works, you provide one or more seed URLs. This URLs are fetched/parsed and the new discovered links are stored for the next iteration.