Source code for capreolus.index.anserini

import math
import os
import subprocess

from capreolus import ConfigOption, constants, get_logger
from capreolus.utils.common import Anserini

from . import Index

[docs]logger = get_logger(__name__) # pylint: disable=invalid-name
[docs]MAX_THREADS = constants["MAX_THREADS"]
[docs]@Index.register class AnseriniIndex(Index):
[docs] module_name = "anserini"
[docs] config_spec = [ ConfigOption("indexstops", False, "should stopwords be indexed? (if False, stopwords are removed)"), ConfigOption("stemmer", "porter", "stemmer: porter, krovetz, or none"),
] def _create_index(self): outdir = self.get_index_path() collection_path, document_type, generator_type = self.collection.get_path_and_types() anserini_fat_jar = Anserini.get_fat_jar() cmd = [ "java", "-classpath", anserini_fat_jar, "-Xms512M", "-Xmx31G", "-Dapp.name='IndexCollection'", "io.anserini.index.IndexCollection", "-collection", document_type, "-generator", generator_type, "-threads", str(MAX_THREADS), "-input", collection_path, "-index", outdir, "-stemmer", "none" if self.config["stemmer"] is None else self.config["stemmer"], ] if self.config["indexstops"]: cmd += ["-keepStopwords"] if not self.collection.is_large_collection: cmd += [ "-storePositions", "-storeDocvectors", "-storeContents", ] logger.info("building index %s", outdir) logger.debug(cmd) os.makedirs(os.path.basename(outdir), exist_ok=True) app = subprocess.Popen(cmd, stdout=subprocess.PIPE, universal_newlines=True) # Anserini output is verbose, so ignore DEBUG log lines and send other output through our logger for line in app.stdout: Anserini.filter_and_log_anserini_output(line, logger) app.wait() if app.returncode != 0: raise RuntimeError("command failed")
[docs] def get_docs(self, doc_ids): # if self.collection.is_large_collection: # return self.get_documents_from_disk(doc_ids) return [self.get_doc(doc_id) for doc_id in doc_ids]
[docs] def get_doc(self, docid): try: if not hasattr(self, "index_reader_utils") or self.index_reader_utils is None: self.open() return self.index_reader_utils.documentContents(self.reader, self.JString(docid)) except Exception as e: raise
[docs] def get_df(self, term): # returns 0 for missing terms if not hasattr(self, "reader") or self.reader is None: self.open() jterm = self.JTerm("contents", term) return self.reader.docFreq(jterm)
[docs] def get_idf(self, term): """BM25's IDF with a floor of 0""" df = self.get_df(term) idf = (self.numdocs - df + 0.5) / (df + 0.5) idf = math.log(1 + idf) return max(idf, 0)
[docs] def open(self): from jnius import autoclass index_path = self.get_index_path().as_posix() JIndexReaderUtils = autoclass("io.anserini.index.IndexReaderUtils") self.index_reader_utils = JIndexReaderUtils() JFile = autoclass("java.io.File") JFSDirectory = autoclass("org.apache.lucene.store.FSDirectory") fsdir = JFSDirectory.open(JFile(index_path).toPath()) self.reader = autoclass("org.apache.lucene.index.DirectoryReader").open(fsdir) self.numdocs = self.reader.numDocs() self.JTerm = autoclass("org.apache.lucene.index.Term") self.JString = autoclass("java.lang.String")