use crate::errors::{Error, SummaResult};
use crate::proto;
use crate::services::IndexService;
use std::cmp::Reverse;
use std::collections::{BinaryHeap, HashMap};
use tonic::{Request, Response, Status};
pub struct ReflectionApiImpl {
index_service: IndexService,
}
impl ReflectionApiImpl {
pub fn new(index_service: &IndexService) -> SummaResult<ReflectionApiImpl> {
Ok(ReflectionApiImpl {
index_service: index_service.clone(),
})
}
}
#[tonic::async_trait]
impl proto::reflection_api_server::ReflectionApi for ReflectionApiImpl {
async fn get_top_terms(&self, proto_request: Request<proto::GetTopTermsRequest>) -> Result<Response<proto::GetTopTermsResponse>, Status> {
let proto_request = proto_request.into_inner();
let index_holder = self.index_service.get_index_holder(&proto_request.index_alias)?;
let field = index_holder
.fields()
.get_field(&proto_request.field_name)
.ok_or_else(|| Error::FieldDoesNotExist(proto_request.field_name.to_owned()))?;
let top_k = proto_request.top_k.try_into().unwrap();
let mut per_segment = HashMap::new();
for segment_reader in index_holder.index_reader().searcher().segment_readers() {
let inverted_index = segment_reader.inverted_index(field).unwrap();
let mut top_k_heap = BinaryHeap::new();
let mut term_stream = inverted_index.terms().stream()?;
while let Some((term, term_info)) = term_stream.next() {
if top_k_heap.len() < top_k {
top_k_heap.push(Reverse((term_info.doc_freq, term.to_vec())));
} else if top_k_heap.peek().unwrap().0 .0 < term_info.doc_freq {
top_k_heap.push(Reverse((term_info.doc_freq, term.to_vec())));
top_k_heap.pop();
}
}
print!("{:?}", top_k_heap);
per_segment.insert(
segment_reader.segment_id().short_uuid_string(),
proto::SegmentTerms {
term_infos: top_k_heap
.into_sorted_vec()
.iter()
.map(|Reverse((doc_freq, key))| proto::TermInfo {
key: key.to_vec(),
doc_freq: *doc_freq,
})
.collect(),
},
);
}
let response = proto::GetTopTermsResponse { per_segment };
Ok(Response::new(response))
}
}