add list_fields api

quickwit/quickwit-proto/protos/quickwit/search.proto

@@ -72,6 +72,10 @@ service SearchService {
   rpc GetKV(GetKVRequest) returns (GetKVResponse);
 
   rpc ReportSplits(ReportSplitsRequest) returns (ReportSplitsResponse);
+
+  rpc ListFields(ListFieldsRequest) returns (ListFieldsResponse);
+
+  rpc LeafListFields(LeafListFieldsRequest) returns (ListFieldsResponse);
 }
 
 /// Scroll Request
@@ -111,6 +115,57 @@ message ReportSplitsRequest {
 
 message ReportSplitsResponse {}
 
+// -- ListFields -------------------
+
+message ListFieldsRequest{
+  // Optional limit query to a set of indexes.
+  repeated string index_id = 1;
+  // Optional limit query to a set of splits.
+  repeated string split_id = 2;
+  // Optional limit query to a list of fields
+  // Wildcard expressions are supported.
+  repeated string fields = 3;
+
+  // Control if the the request will fail if split_ids contains a split that does not exist. 
+  // optional bool fail_on_missing_index = 3;
+}
+
+message LeafListFieldsRequest{
+  // The index id
+  string index_id = 1;
+  // The index uri
+  string index_uri = 2;
+  // Index split ids to apply the query on.
+  // This ids are resolved from the index_uri defined in the search_request.
+  repeated SplitIdAndFooterOffsets split_offsets = 3;
+
+  // Optional limit query to a list of fields
+  // Wildcard expressions are supported.
+  repeated string fields = 4;
+}
+
+message ListFieldsResponse{
+  repeated ListFieldsEntryResponse fields = 1;
+}
+
+message ListFieldsEntryResponse{
+  // The field name
+  string field_name = 1;
+  // The tantivy field type
+  int32 field_type = 2;
+  // The index ids the field exists
+  repeated string index_ids = 3;
+  // True means the field is searchable (indexed) in at least some indices.
+  // False means the field is not searchable in any indices.
+  bool searchable = 4;
+  // True means the field is aggregatable (fast) in at least some indices.
+  // False means the field is not aggregatable in any indices.
+  bool aggregatable = 5;
+  // The index ids the field exists, but is not searchable.
+  repeated string non_searchable_index_ids = 6;
+  // The index ids the field exists, but is not aggregatable
+  repeated string non_aggregatable_index_ids = 7;
+}
 
 // -- Search -------------------
 

quickwit/quickwit-search/Cargo.toml

@@ -50,6 +50,7 @@ quickwit-opentelemetry = { workspace = true }
 quickwit-proto = { workspace = true }
 quickwit-query = { workspace = true }
 quickwit-storage = { workspace = true }
+quickwit-indexing = { workspace = true }
 
 [dev-dependencies]
 assert-json-diff = { workspace = true }

quickwit/quickwit-search/src/client.rs

@@ -140,6 +140,24 @@ impl SearchServiceClient {
         }
     }
 
+    /// Perform leaf search.
+    pub async fn leaf_list_fields(
+        &mut self,
+        request: quickwit_proto::search::LeafListFieldsRequest,
+    ) -> crate::Result<quickwit_proto::search::ListFieldsResponse> {
+        match &mut self.client_impl {
+            SearchServiceClientImpl::Grpc(grpc_client) => {
+                let tonic_request = Request::new(request);
+                let tonic_response = grpc_client
+                    .leaf_list_fields(tonic_request)
+                    .await
+                    .map_err(|tonic_error| parse_grpc_error(&tonic_error))?;
+                Ok(tonic_response.into_inner())
+            }
+            SearchServiceClientImpl::Local(service) => service.leaf_list_fields(request).await,
+        }
+    }
+
     /// Perform leaf stream.
     pub async fn leaf_search_stream(
         &mut self,

quickwit/quickwit-search/src/cluster_client.rs

@@ -23,9 +23,9 @@ use base64::Engine;
 use futures::future::ready;
 use futures::{Future, StreamExt};
 use quickwit_proto::search::{
-    FetchDocsRequest, FetchDocsResponse, GetKvRequest, LeafListTermsRequest, LeafListTermsResponse,
-    LeafSearchRequest, LeafSearchResponse, LeafSearchStreamRequest, LeafSearchStreamResponse,
-    PutKvRequest,
+    FetchDocsRequest, FetchDocsResponse, GetKvRequest, LeafListFieldsRequest, LeafListTermsRequest,
+    LeafListTermsResponse, LeafSearchRequest, LeafSearchResponse, LeafSearchStreamRequest,
+    LeafSearchStreamResponse, ListFieldsResponse, PutKvRequest,
 };
 use tantivy::aggregation::intermediate_agg_result::IntermediateAggregationResults;
 use tokio::sync::mpsc::error::SendError;
@@ -112,6 +112,15 @@ impl ClusterClient {
         response_res
     }
 
+    /// Leaf search with retry on another node client.
+    pub async fn leaf_list_fields(
+        &self,
+        request: LeafListFieldsRequest,
+        mut client: SearchServiceClient,
+    ) -> crate::Result<ListFieldsResponse> {
+        client.leaf_list_fields(request.clone()).await
+    }
+
     /// Leaf search stream with retry on another node client.
     pub async fn leaf_search_stream(
         &self,