WARC Extractor
If you have WARC files with HTML and need to extract text from there, this is
the project that you need. You typically use it to
extract text information from Common Crawl.
Common Crawl
Common Crawl (http://commoncrawl.org) is a copy of the Internet. Each month they release all the websites that they crawled in the previous month. This is a lot of data (many terabytes) and a good source dataset for many NLP tasks.
In many cases you probaby don't need to use all the data. Is it not difficult to get just a few files.
Here is how:
- Go to http://commoncrawl.org/the-data/get-started/ to the "Data Location" section
- Copy the url for the data you're interested in
- E.g.
s3://commoncrawl/crawl-data/CC-MAIN-2018-09(for February 2018)
- E.g.
- Replace
s3://commoncrawl/crawl-data/withhttps://commoncrawl.s3.amazonaws.com/ - To get paths to all the files in the archive, you need to get the
warc.paths.gzfile- It is located in the root of each month's folder
- So to get the paths for February 2018, use https://commoncrawl.s3.amazonaws.com/crawl-data/CC-MAIN-2018-05/warc.paths.gz
- Next sample 10 (or 100 or whatever) files from this list
- Append
https://commoncrawl.s3.amazonaws.com/to each path, download
In script:
wget https://commoncrawl.s3.amazonaws.com/crawl-data/CC-MAIN-2018-09/warc.paths.gz
zcat warc.paths.gz \
| head -n 100 \
| awk '{ print "https://commoncrawl.s3.amazonaws.com/" $0}' \
> files.txt
cat files.txt | parallel --gnu "wget {}"
Here we take top 100 files from this list and download them with GNU Parallel
Running WARC Extractor
First you need to build it:
./build.sh
You need to have java and maven to do it.
Next, you run it:
java -cp libs/*:. warc.WarcPreparationJob \
--input /path/to/input/warc/files \
--output /output/path \
--languages en,de
Parameters:
--input: path to the downloaded WARC files--output: path where the results should be stored--languages: languages you want to keep, all others will be discarded