Phrase weight

This commit is contained in:
Paul Masurel
2018-09-10 09:26:33 +09:00
parent a78f4cca37
commit e32dba1a97
12 changed files with 61 additions and 191 deletions

View File

@@ -7,7 +7,6 @@ use query::{Scorer, Weight};
use schema::{Field, IndexRecordOption};
use termdict::{TermDictionary, TermStreamer};
use Result;
use query::weight::MatchingTerms;
use SkipResult;
use Term;
use DocId;
@@ -41,47 +40,6 @@ impl<A> Weight for AutomatonWeight<A>
where
A: Automaton,
{
fn matching_terms(&self,
reader: &SegmentReader,
matching_terms: &mut MatchingTerms) -> Result<()> {
let max_doc = reader.max_doc();
let mut doc_bitset = BitSet::with_max_value(max_doc);
let inverted_index = reader.inverted_index(self.field);
let term_dict = inverted_index.terms();
let mut term_stream = self.automaton_stream(term_dict);
let doc_ids = matching_terms.sorted_doc_ids();
let mut docs_matching_current_term: Vec<DocId> = vec![];
let mut term_buffer: Vec<u8> = vec![];
while term_stream.advance() {
docs_matching_current_term.clear();
let term_info = term_stream.value();
let mut segment_postings = inverted_index.read_postings_from_terminfo(term_info, IndexRecordOption::Basic);
for &doc_id in &doc_ids {
match segment_postings.skip_next(doc_id) {
SkipResult::Reached => {
docs_matching_current_term.push(doc_id);
}
SkipResult::OverStep => {}
SkipResult::End => {}
}
}
if !docs_matching_current_term.is_empty() {
term_buffer.clear();
let term_ord = term_stream.term_ord();
inverted_index.terms().ord_to_term(term_ord, &mut term_buffer);
let term = Term::from_field_bytes(self.field, &term_buffer[..]);
for &doc_id in &docs_matching_current_term {
matching_terms.add_term(doc_id, term.clone(), 1f32);
}
}
}
Ok(())
}
fn scorer(&self, reader: &SegmentReader) -> Result<Box<Scorer>> {
let max_doc = reader.max_doc();
let mut doc_bitset = BitSet::with_max_value(max_doc);

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@@ -6,6 +6,7 @@ use query::Weight;
use schema::IndexRecordOption;
use schema::Term;
use Result;
use std::collections::BTreeSet;
use Searcher;
/// The boolean query combines a set of queries
@@ -40,6 +41,7 @@ impl From<Vec<(Occur, Box<Query>)>> for BooleanQuery {
}
impl Query for BooleanQuery {
fn weight(&self, searcher: &Searcher, scoring_enabled: bool) -> Result<Box<Weight>> {
let sub_weights = self.subqueries
.iter()
@@ -49,6 +51,12 @@ impl Query for BooleanQuery {
.collect::<Result<_>>()?;
Ok(Box::new(BooleanWeight::new(sub_weights, scoring_enabled)))
}
fn query_terms(&self, term_set: &mut BTreeSet<Term>) {
for (_occur, subquery) in &self.subqueries {
subquery.query_terms(term_set);
}
}
}
impl BooleanQuery {

View File

@@ -13,7 +13,6 @@ use query::Weight;
use std::borrow::Borrow;
use std::collections::HashMap;
use Result;
use query::MatchingTerms;
fn scorer_union<TScoreCombiner>(scorers: Vec<Box<Scorer>>) -> Box<Scorer>
where
@@ -108,14 +107,6 @@ impl BooleanWeight {
}
impl Weight for BooleanWeight {
fn matching_terms(&self, reader: &SegmentReader, matching_terms: &mut MatchingTerms) -> Result<()> {
for (_, weight) in &self.weights {
weight.matching_terms(reader, matching_terms)?;
}
Ok(())
}
fn scorer(&self, reader: &SegmentReader) -> Result<Box<Scorer>> {
if self.weights.is_empty() {
Ok(Box::new(EmptyScorer))

View File

@@ -27,8 +27,6 @@ mod weight;
mod vec_docset;
pub(crate) mod score_combiner;
pub use self::weight::MatchingTerms;
pub use self::intersection::Intersection;
pub use self::union::Union;

View File

@@ -6,6 +6,7 @@ use query::Query;
use query::Weight;
use schema::{Field, Term};
use Result;
use std::collections::BTreeSet;
/// `PhraseQuery` matches a specific sequence of words.
///
@@ -107,4 +108,10 @@ impl Query for PhraseQuery {
)))
}
}
fn query_terms(&self, term_set: &mut BTreeSet<Term>) {
for (_, query_term) in &self.phrase_terms {
term_set.insert(query_term.clone());
}
}
}

View File

@@ -7,7 +7,6 @@ use query::Weight;
use schema::IndexRecordOption;
use schema::Term;
use Result;
use query::MatchingTerms;
pub struct PhraseWeight {
phrase_terms: Vec<(usize, Term)>,
@@ -32,10 +31,6 @@ impl PhraseWeight {
impl Weight for PhraseWeight {
fn matching_terms(&self, reader: &SegmentReader, matching_terms: &mut MatchingTerms) -> Result<()> {
unimplemented!();
}
fn scorer(&self, reader: &SegmentReader) -> Result<Box<Scorer>> {
let similarity_weight = self.similarity_weight.clone();
let field = self.phrase_terms[0].1.field();

View File

@@ -6,7 +6,8 @@ use std::fmt;
use Result;
use SegmentLocalId;
use DocAddress;
use query::weight::MatchingTerms;
use std::collections::BTreeSet;
use Term;
/// The `Query` trait defines a set of documents and a scoring method
/// for those documents.
@@ -60,6 +61,8 @@ pub trait Query: QueryClone + downcast::Any + fmt::Debug {
Ok(result)
}
fn query_terms(&self, term_set: &mut BTreeSet<Term>) {}
/// Search works as follows :
///
/// First the weight object associated to the query is created.

View File

@@ -11,7 +11,6 @@ use std::collections::Bound;
use std::ops::Range;
use termdict::{TermDictionary, TermStreamer};
use Result;
use query::MatchingTerms;
fn map_bound<TFrom, TTo, Transform: Fn(&TFrom) -> TTo>(
bound: &Bound<TFrom>,
@@ -276,10 +275,6 @@ impl RangeWeight {
impl Weight for RangeWeight {
fn matching_terms(&self, reader: &SegmentReader, matching_terms: &mut MatchingTerms) -> Result<()> {
unimplemented!();
}
fn scorer(&self, reader: &SegmentReader) -> Result<Box<Scorer>> {
let max_doc = reader.max_doc();
let mut doc_bitset = BitSet::with_max_value(max_doc);

View File

@@ -6,6 +6,7 @@ use schema::IndexRecordOption;
use Result;
use Searcher;
use Term;
use std::collections::BTreeSet;
/// A Term query matches all of the documents
/// containing a specific term.
@@ -110,4 +111,7 @@ impl Query for TermQuery {
fn weight(&self, searcher: &Searcher, scoring_enabled: bool) -> Result<Box<Weight>> {
Ok(Box::new(self.specialized_weight(searcher, scoring_enabled)))
}
fn query_terms(&self, term_set: &mut BTreeSet<Term>) {
term_set.insert(self.term.clone());
}
}

View File

@@ -9,7 +9,6 @@ use schema::IndexRecordOption;
use Result;
use Term;
use SkipResult;
use query::weight::MatchingTerms;
pub struct TermWeight {
term: Term,
@@ -40,26 +39,6 @@ impl Weight for TermWeight {
}
}
fn matching_terms(&self,
reader: &SegmentReader,
matching_terms: &mut MatchingTerms) -> Result<()> {
let doc_ids = matching_terms.sorted_doc_ids();
let mut scorer = self.scorer(reader)?;
for doc_id in doc_ids {
match scorer.skip_next(doc_id) {
SkipResult::Reached => {
matching_terms.add_term(doc_id, self.term.clone(), 1f32);
}
SkipResult::OverStep => {}
SkipResult::End => {
break;
}
}
}
Ok(())
}
fn count(&self, reader: &SegmentReader) -> Result<u32> {
if reader.num_deleted_docs() == 0 {
let field = self.term.field();

View File

@@ -7,36 +7,6 @@ use Term;
use std::collections::BTreeMap;
use std::collections::HashMap;
pub struct MatchingTerms {
doc_to_terms: BTreeMap<DocId, HashMap<Term, f32>>
}
impl MatchingTerms {
pub fn from_doc_ids(doc_ids: &[DocId]) -> MatchingTerms {
MatchingTerms {
doc_to_terms: doc_ids
.iter()
.cloned()
.map(|doc_id| (doc_id, HashMap::default()))
.collect()
}
}
pub fn terms_for_doc(&self, doc_id: DocId) -> Option<&HashMap<Term, f32>> {
self.doc_to_terms.get(&doc_id)
}
pub fn sorted_doc_ids(&self) -> Vec<DocId> {
self.doc_to_terms.keys().cloned().collect()
}
pub fn add_term(&mut self, doc_id: DocId, term: Term, score: f32) {
if let Some(terms) = self.doc_to_terms.get_mut(&doc_id) {
terms.insert(term, score);
}
}
}
/// A Weight is the specialization of a Query
/// for a given set of segments.
///
@@ -46,10 +16,6 @@ pub trait Weight {
/// See [`Query`](./trait.Query.html).
fn scorer(&self, reader: &SegmentReader) -> Result<Box<Scorer>>;
fn matching_terms(&self, reader: &SegmentReader, matching_terms: &mut MatchingTerms) -> Result<()> {
Ok(())
}
/// Returns the number documents within the given `SegmentReader`.
fn count(&self, reader: &SegmentReader) -> Result<u32> {
Ok(self.scorer(reader)?.count())

View File

@@ -11,11 +11,11 @@ use query::Query;
use DocAddress;
use DocId;
use Searcher;
use query::MatchingTerms;
use schema::Field;
use std::collections::HashMap;
use SegmentLocalId;
use error::TantivyError;
use std::collections::BTreeSet;
#[derive(Debug)]
pub struct HighlightSection {
@@ -129,9 +129,9 @@ impl Snippet {
/// Fragments must be valid in the sense that `&text[fragment.start..fragment.stop]`\
/// has to be a valid string.
fn search_fragments<'a>(
tokenizer: Box<BoxedTokenizer>,
tokenizer: &BoxedTokenizer,
text: &'a str,
terms: BTreeMap<String, f32>,
terms: &BTreeMap<String, f32>,
max_num_chars: usize,
) -> Vec<FragmentCandidate> {
let mut token_stream = tokenizer.token_stream(text);
@@ -199,75 +199,41 @@ fn select_best_fragment_combination<'a>(
}
const DEFAULT_MAX_NUM_CHARS: usize = 150;
fn compute_matching_terms(query: &Query, searcher: &Searcher, doc_addresses: &[DocAddress]) -> Result<HashMap<SegmentLocalId, MatchingTerms>> {
let weight = query.weight(searcher, false)?;
let mut doc_groups = doc_addresses
.iter()
.group_by(|doc_address| doc_address.0);
let mut matching_terms_per_segment: HashMap<SegmentLocalId, MatchingTerms> = HashMap::new();
for (segment_ord, doc_addrs) in doc_groups.into_iter() {
let doc_addrs_vec: Vec<DocId> = doc_addrs.map(|doc_addr| doc_addr.1).collect();
let mut matching_terms = MatchingTerms::from_doc_ids(&doc_addrs_vec[..]);
let segment_reader = searcher.segment_reader(segment_ord);
weight.matching_terms(segment_reader, &mut matching_terms)?;
matching_terms_per_segment.insert(segment_ord, matching_terms);
}
Ok(matching_terms_per_segment)
pub struct SnippetGenerator {
terms_text: BTreeMap<String, f32>,
tokenizer: Box<BoxedTokenizer>,
max_num_chars: usize
}
pub fn generate_snippet(
searcher: &Searcher,
query: &Query,
field: Field,
doc_addresses: &[DocAddress],
max_num_chars: usize) -> Result<Vec<Snippet>> {
let mut doc_address_ords: Vec<usize> = (0..doc_addresses.len()).collect();
doc_address_ords.sort_by_key(|k| doc_addresses[*k]);
let mut snippets = vec![];
let matching_terms_per_segment_local_id = compute_matching_terms(query, searcher, doc_addresses)?;
for &doc_address_ord in &doc_address_ords {
let doc_address = doc_addresses[doc_address_ord];
let segment_ord: u32 = doc_address.segment_ord();
let doc = searcher.doc(&doc_address)?;
let mut text = String::new();
for value in doc.get_all(field) {
text.push_str(value.text());
}
if let Some(matching_terms) = matching_terms_per_segment_local_id.get(&segment_ord) {
let tokenizer = searcher.index().tokenizer_for_field(field)?;
if let Some(terms) = matching_terms.terms_for_doc(doc_address.doc()) {
let terms: BTreeMap<String, f32> = terms
.iter()
.map(|(term, score)| (term.text().to_string(), *score))
.collect();
let fragment_candidates = search_fragments(tokenizer,
&text,
terms,
max_num_chars);
let snippet = select_best_fragment_combination(fragment_candidates, &text);
snippets.push(snippet);
} else {
snippets.push(Snippet::empty());
}
} else {
}
impl SnippetGenerator {
pub fn new(searcher: &Searcher,
query: &Query,
field: Field) -> Result<SnippetGenerator> {
let mut terms = BTreeSet::new();
query.query_terms(&mut terms);
let terms_text: BTreeMap<String, f32> = terms.into_iter()
.filter(|term| term.field() == field)
.map(|term| (term.text().to_string(), 1f32))
.collect();
let tokenizer = searcher.index().tokenizer_for_field(field)?;
Ok(SnippetGenerator {
terms_text,
tokenizer,
max_num_chars: DEFAULT_MAX_NUM_CHARS
})
}
// reorder the snippets
for i in 0..doc_addresses.len() {
snippets.swap(i, doc_address_ords[i]);
}
pub fn snippet(&self, text: &str) -> Snippet {
let fragment_candidates = search_fragments(&*self.tokenizer,
&text,
&self.terms_text,
self.max_num_chars);
let snippet = select_best_fragment_combination(fragment_candidates, &text);
snippet
Ok(snippets)
}
}
#[cfg(test)]
@@ -294,7 +260,7 @@ Rust won first place for \"most loved programming language\" in the Stack Overfl
terms.insert(String::from("rust"), 1.0);
terms.insert(String::from("language"), 0.9);
let fragments = search_fragments(boxed_tokenizer, &text, terms, 100);
let fragments = search_fragments(&*boxed_tokenizer, &text, &terms, 100);
assert_eq!(fragments.len(), 7);
{
let first = fragments.iter().nth(0).unwrap();
@@ -315,7 +281,7 @@ Rust won first place for \"most loved programming language\" in the Stack Overfl
let mut terms = BTreeMap::new();
terms.insert(String::from("c"), 1.0);
let fragments = search_fragments(boxed_tokenizer, &text, terms, 3);
let fragments = search_fragments(&*boxed_tokenizer, &text, &terms, 3);
assert_eq!(fragments.len(), 1);
{
@@ -339,7 +305,7 @@ Rust won first place for \"most loved programming language\" in the Stack Overfl
let mut terms = BTreeMap::new();
terms.insert(String::from("f"), 1.0);
let fragments = search_fragments(boxed_tokenizer, &text, terms, 3);
let fragments = search_fragments(&*boxed_tokenizer, &text, &terms, 3);
assert_eq!(fragments.len(), 2);
{
@@ -364,7 +330,7 @@ Rust won first place for \"most loved programming language\" in the Stack Overfl
terms.insert(String::from("f"), 1.0);
terms.insert(String::from("a"), 0.9);
let fragments = search_fragments(boxed_tokenizer, &text, terms, 7);
let fragments = search_fragments(&*boxed_tokenizer, &text, &terms, 7);
assert_eq!(fragments.len(), 2);
{
@@ -388,7 +354,7 @@ Rust won first place for \"most loved programming language\" in the Stack Overfl
let mut terms = BTreeMap::new();
terms.insert(String::from("z"), 1.0);
let fragments = search_fragments(boxed_tokenizer, &text, terms, 3);
let fragments = search_fragments(&*boxed_tokenizer, &text, &terms, 3);
assert_eq!(fragments.len(), 0);
@@ -404,7 +370,7 @@ Rust won first place for \"most loved programming language\" in the Stack Overfl
let text = "a b c d";
let terms = BTreeMap::new();
let fragments = search_fragments(boxed_tokenizer, &text, terms, 3);
let fragments = search_fragments(&*boxed_tokenizer, &text, &terms, 3);
assert_eq!(fragments.len(), 0);
let snippet = select_best_fragment_combination(fragments, &text);