Ranking of aggregated search results based on relevancy of the search result to the user's search query (#549)

* add sorting by relevance and merge new changes

* fix conflicts

* Update src/models/aggregation_models.rs

Co-authored-by: neon_arch <mustafadhuleb53@gmail.com>

* Update src/models/aggregation_models.rs

Co-authored-by: neon_arch <mustafadhuleb53@gmail.com>

* Update Cargo.toml

Co-authored-by: neon_arch <mustafadhuleb53@gmail.com>

* Update Cargo.toml

Co-authored-by: neon_arch <mustafadhuleb53@gmail.com>

* Update Cargo.toml

Co-authored-by: neon_arch <mustafadhuleb53@gmail.com>

* enable non-static-synonyms features

---------

Co-authored-by: neon_arch <mustafadhuleb53@gmail.com>
This commit is contained in:
Spencer 2024-03-25 09:16:49 +00:00 committed by GitHub
parent c584a7d601
commit bb50e8bb25
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4 changed files with 296 additions and 41 deletions

View file

@ -4,7 +4,11 @@
use super::engine_models::EngineError;
use serde::{Deserialize, Serialize};
use smallvec::SmallVec;
#[cfg(any(
feature = "use-synonyms-search",
feature = "use-non-static-synonyms-search"
))]
use thesaurus::synonyms;
/// A named struct to store the raw scraped search results scraped search results from the
/// upstream search engines before aggregating it.It derives the Clone trait which is needed
/// to write idiomatic rust using `Iterators`.
@ -20,6 +24,8 @@ pub struct SearchResult {
pub description: String,
/// The names of the upstream engines from which this results were provided.
pub engine: SmallVec<[String; 0]>,
/// The td-tdf score of the result in regards to the title, url and description and the user's query
pub relevance_score: f32,
}
impl SearchResult {
@ -37,9 +43,49 @@ impl SearchResult {
title: title.to_owned(),
url: url.to_owned(),
description: description.to_owned(),
relevance_score: 0.0,
engine: engine.iter().map(|name| name.to_string()).collect(),
}
}
/// calculates and update the relevance score of the current search.
/// # Arguments
///
/// * query - the query string used to obtain the results
///
///
pub fn calculate_relevance(&mut self, query: &str) {
use stop_words::{get, LANGUAGE};
// when language settings can change to any of the ones supported on this crate: https://docs.rs/crate/stop-words/0.8.0
let documents = [
self.title.clone(),
self.url.clone(),
self.description.clone(),
];
let stop_words = get(LANGUAGE::English);
let punctuation = [
".".to_owned(),
",".to_owned(),
":".to_owned(),
";".to_owned(),
"!".to_owned(),
"?".to_owned(),
"(".to_owned(),
")".to_owned(),
"[".to_owned(),
"]".to_owned(),
"{".to_owned(),
"}".to_owned(),
"\"".to_owned(),
"'".to_owned(),
"<".to_owned(),
">".to_owned(),
];
self.relevance_score = calculate_tf_idf(query, &documents, &stop_words, &punctuation);
}
/// A function which adds the engine name provided as a string into a vector of strings.
///
@ -182,3 +228,53 @@ impl SearchResults {
self.no_engines_selected = true;
}
}
/// Helper function to calculate the tf-idf for the search query.
/// <br> The approach is as [`as`](https://en.wikipedia.org/wiki/Tf%E2%80%93idf).
/// <br> Find a sample article about TF-IDF [`here`](https://medium.com/analytics-vidhya/tf-idf-term-frequency-technique-easiest-explanation-for-text-classification-in-nlp-with-code-8ca3912e58c3)
/// ### Arguments
/// * `query` - a user's search query
/// * `documents` - a list of text used for comparision (url, title, description)
/// * `stop_words` - A list of language specific stop words.
/// * `punctuation` - list of punctuation symbols.
/// ### Returns
/// * `score` - The average tf-idf score of the word tokens (and synonyms) in the query
fn calculate_tf_idf(
query: &str,
documents: &[String],
stop_words: &[String],
punctuation: &[String],
) -> f32 {
use keyword_extraction::{
tf_idf::{TfIdf, TfIdfParams},
tokenizer::Tokenizer,
};
let params = TfIdfParams::UnprocessedDocuments(documents, stop_words, Some(punctuation));
let tf_idf = TfIdf::new(params);
let tokener = Tokenizer::new(query, stop_words, Some(punctuation));
let query_tokens = tokener.split_into_words();
let mut search_tokens = vec![];
for token in query_tokens {
#[cfg(any(
feature = "use-synonyms-search",
feature = "use-non-static-synonyms-search"
))]
{
// find some synonyms and add them to the search (from wordnet or moby if feature is enabled)
let synonyms = synonyms(&token);
search_tokens.extend(synonyms)
}
search_tokens.push(token);
}
let mut total_score = 0.0f32;
for token in search_tokens.iter() {
total_score += tf_idf.get_score(token);
}
let result = total_score / (search_tokens.len() as f32);
f32::from(!result.is_nan()) * result
}

View file

@ -8,6 +8,7 @@ use crate::models::{
aggregation_models::{EngineErrorInfo, SearchResult, SearchResults},
engine_models::{EngineError, EngineHandler},
};
use error_stack::Report;
use futures::stream::FuturesUnordered;
use regex::Regex;
@ -184,7 +185,17 @@ pub async fn aggregate(
drop(blacklist_map);
}
let results: Vec<SearchResult> = result_map.iter().map(|(_, value)| value.clone()).collect();
let mut results: Vec<SearchResult> = result_map
.iter()
.map(|(_, value)| {
let mut copy = value.clone();
if !copy.url.contains("temu.com") {
copy.calculate_relevance(query.as_str())
}
copy
})
.collect();
sort_search_results(&mut results);
Ok(SearchResults::new(results, &engine_errors_info))
}
@ -233,7 +244,21 @@ pub async fn filter_with_lists(
Ok(())
}
/// Sorts SearchResults by relevance score.
/// <br> sort_unstable is used as its faster,stability is not an issue on our side.
/// For reasons why, check out [`this`](https://rust-lang.github.io/rfcs/1884-unstable-sort.html)
/// # Arguments
/// * `results` - A mutable slice or Vec of SearchResults
///
fn sort_search_results(results: &mut [SearchResult]) {
results.sort_unstable_by(|a, b| {
use std::cmp::Ordering;
b.relevance_score
.partial_cmp(&a.relevance_score)
.unwrap_or(Ordering::Less)
})
}
#[cfg(test)]
mod tests {
use super::*;
@ -252,6 +277,7 @@ mod tests {
url: "https://www.example.com".to_owned(),
description: "This domain is for use in illustrative examples in documents."
.to_owned(),
relevance_score: 0.0,
engine: smallvec!["Google".to_owned(), "Bing".to_owned()],
},
));
@ -262,6 +288,7 @@ mod tests {
url: "https://www.rust-lang.org/".to_owned(),
description: "A systems programming language that runs blazingly fast, prevents segfaults, and guarantees thread safety.".to_owned(),
engine: smallvec!["Google".to_owned(), "DuckDuckGo".to_owned()],
relevance_score:0.0
},)
);
@ -302,6 +329,7 @@ mod tests {
description: "This domain is for use in illustrative examples in documents."
.to_owned(),
engine: smallvec!["Google".to_owned(), "Bing".to_owned()],
relevance_score: 0.0,
},
));
map_to_be_filtered.push((
@ -311,6 +339,7 @@ mod tests {
url: "https://www.rust-lang.org/".to_owned(),
description: "A systems programming language that runs blazingly fast, prevents segfaults, and guarantees thread safety.".to_owned(),
engine: smallvec!["Google".to_owned(), "DuckDuckGo".to_owned()],
relevance_score:0.0
},
));
@ -367,6 +396,7 @@ mod tests {
description: "This domain is for use in illustrative examples in documents."
.to_owned(),
engine: smallvec!["Google".to_owned(), "Bing".to_owned()],
relevance_score: 0.0,
},
));