feat: Aggregations API (#288)

src/searcher.rs

@@ -1,9 +1,11 @@
 #![allow(clippy::new_ret_no_self)]
 
 use crate::{document::Document, query::Query, to_pyerr};
+use pyo3::types::PyDict;
 use pyo3::{basic::CompareOp, exceptions::PyValueError, prelude::*};
 use serde::{Deserialize, Serialize};
 use tantivy as tv;
+use tantivy::aggregation::AggregationCollector;
 use tantivy::collector::{Count, MultiCollector, TopDocs};
 use tantivy::TantivyDocument;
 // Bring the trait into scope. This is required for the `to_named_doc` method.
@@ -233,6 +235,35 @@ impl Searcher {
         })
     }
 
+    #[pyo3(signature = (query, agg))]
+    fn aggregate(
+        &self,
+        py: Python,
+        query: &Query,
+        agg: Py<PyDict>,
+    ) -> PyResult<Py<PyDict>> {
+        let py_json = py.import_bound("json")?;
+        let agg_query_str = py_json.call_method1("dumps", (agg,))?.to_string();
+
+        let agg_str = py.allow_threads(move || {
+            let agg_collector = AggregationCollector::from_aggs(
+                serde_json::from_str(&agg_query_str).map_err(to_pyerr)?,
+                Default::default(),
+            );
+            let agg_res = self
+                .inner
+                .search(query.get(), &agg_collector)
+                .map_err(to_pyerr)?;
+
+            serde_json::to_string(&agg_res).map_err(to_pyerr)
+        })?;
+
+        let agg_dict = py_json.call_method1("loads", (agg_str,))?;
+        let agg_dict = agg_dict.downcast::<PyDict>()?;
+
+        Ok(agg_dict.clone().unbind())
+    }
+
     /// Returns the overall number of documents in the index.
     #[getter]
     fn num_docs(&self) -> u64 {

tantivy/tantivy.pyi

@@ -289,6 +289,13 @@ class Searcher:
     ) -> SearchResult:
         pass
 
+    def aggregate(
+        self,
+        search_query: Query,
+        agg_query: dict,
+    ) -> dict:
+        pass
+
     @property
     def num_docs(self) -> int:
         pass

tests/conftest.py

@@ -15,10 +15,10 @@ def schema():
 def schema_numeric_fields():
     return (
         SchemaBuilder()
-        .add_integer_field("id", stored=True, indexed=True)
+        .add_integer_field("id", stored=True, indexed=True, fast=True)
-        .add_float_field("rating", stored=True, indexed=True)
+        .add_float_field("rating", stored=True, indexed=True, fast=True)
         .add_boolean_field("is_good", stored=True, indexed=True)
-        .add_text_field("body", stored=True)
+        .add_text_field("body", stored=True, fast=True)
         .build()
     )
 

tests/tantivy_test.py

@@ -64,6 +64,60 @@ class TestClass(object):
 
         assert len(result.hits) == 1
 
+    def test_and_aggregate(self, ram_index_numeric_fields):
+        index = ram_index_numeric_fields
+        query = Query.all_query()
+        agg_query = {
+            "top_hits_req": {
+                "top_hits": {
+                    "size": 2,
+                    "sort": [{"rating": "desc"}],
+                    "from": 0,
+                    "docvalue_fields": ["rating", "id", "body"],
+                }
+            }
+        }
+        searcher = index.searcher()
+        result = searcher.aggregate(query, agg_query)
+        assert isinstance(result, dict)
+        assert "top_hits_req" in result
+        assert len(result["top_hits_req"]["hits"]) == 2
+        for hit in result["top_hits_req"]["hits"]:
+            assert len(hit["docvalue_fields"]) == 3
+
+        assert result == json.loads("""
+{
+"top_hits_req": {
+    "hits": [
+      {
+        "sort": [ 13840124604862955520 ],
+        "docvalue_fields": {
+          "id": [ 2 ],
+          "rating": [ 4.5 ],
+          "body": [ "a", "few", "miles", "south", "of", "soledad", "the", "salinas", "river", "drops", "in", "close", "to", "the", "hillside",
+            "bank", "and", "runs", "deep", "and", "green", "the", "water", "is", "warm", "too", "for", "it", "has", "slipped", "twinkling",
+            "over", "the", "yellow", "sands", "in", "the", "sunlight", "before", "reaching", "the", "narrow", "pool",
+            "on", "one", "side", "of", "the", "river", "the", "golden", "foothill", "slopes", "curve", "up",
+            "to", "the", "strong", "and", "rocky", "gabilan", "mountains", "but", "on", "the", "valley", "side", "the",
+            "water", "is", "lined", "with", "trees", "willows", "fresh", "and", "green", "with", "every", "spring", "carrying", "in", "their", "lower", "leaf",
+            "junctures", "the", "debris", "of", "the", "winter", "s", "flooding", "and", "sycamores", "with", "mottled", "white", "recumbent", "limbs",
+            "and", "branches", "that", "arch", "over", "the", "pool" ]
+        }
+      },
+      {
+        "sort": [ 13838435755002691584 ],
+        "docvalue_fields": {
+          "body": [ "he", "was", "an", "old", "man", "who", "fished", "alone", "in", "a", "skiff", "inthe", "gulf", "stream",
+            "and", "he", "had", "gone", "eighty", "four", "days", "now", "without", "taking", "a", "fish" ],
+          "rating": [ 3.5 ],
+          "id": [ 1 ]
+        }
+      }
+    ]
+  }
+}
+""")
+
     def test_and_query_numeric_fields(self, ram_index_numeric_fields):
         index = ram_index_numeric_fields
         searcher = index.searcher()