def setUp(self):
# Download pre-built CACM index; append a random value to avoid filename clashes.
r = randint(0, 10000000)
self.collection_url = 'https://github.com/castorini/anserini-data/raw/master/CACM/lucene-index.cacm.tar.gz'
self.tarball_name = 'lucene-index.cacm-{}.tar.gz'.format(r)
self.index_dir = 'index{}/'.format(r)
filename, headers = urlretrieve(self.collection_url, self.tarball_name)
tarball = tarfile.open(self.tarball_name)
tarball.extractall(self.index_dir)
tarball.close()
self.searcher = search.SimpleSearcher(f'{self.index_dir}lucene-index.cacm')
