Check for nullptr index_ in all api/index methods (#258)

Author: jparismorgan

src/include/api/flat_l2_index.h

@@ -91,24 +91,36 @@ class IndexFlatL2 {
   // @todo query() or search() -- or both?
   [[nodiscard]] auto query(
       const QueryVectorArray& vectors, size_t top_k) const {
+    if (!index_) {
+      throw std::runtime_error("Cannot query() because there is no index.");
+    }
     return index_->query(vectors, top_k);
   }
 
   void update(
       const FeatureVectorArray& vectors,
       const std::optional<IdVector>& ids = std::nullopt,
       const std::optional<UpdateOptions>& options = std::nullopt) const {
+    if (!index_) {
+      throw std::runtime_error("Cannot update() because there is no index.");
+    }
     index_->update(vectors, ids, options);
   }
 
   void update(
       const URI& vectors_uri,
       const std::optional<IdVector>& ids = std::nullopt,
       const std::optional<UpdateOptions>& options = std::nullopt) const {
+    if (!index_) {
+      throw std::runtime_error("Cannot update() because there is no index.");
+    }
     index_->update(vectors_uri, ids, options);
   }
 
   void remove(const IdVector& ids) const {
+    if (!index_) {
+      throw std::runtime_error("Cannot remove() because there is no index.");
+    }
     index_->remove(ids);
   }
 

src/include/api/ivf_flat_index.h

@@ -338,6 +338,9 @@ class IndexIVFFlat {
           datatype_to_string(feature_datatype_) +
           " != " + datatype_to_string(data_set.feature_type()));
     }
+    if (!index_) {
+      throw std::runtime_error("Cannot add() because there is no index.");
+    }
     index_->add(data_set);
   }
 
@@ -348,6 +351,10 @@ class IndexIVFFlat {
   // todo query() or search() -- or both?
   [[nodiscard]] auto query_infinite_ram(
       const QueryVectorArray& vectors, size_t top_k, size_t nprobe) const {
+    if (!index_) {
+      throw std::runtime_error(
+          "Cannot query_infinite_ram() because there is no index.");
+    }
     return index_->query_infinite_ram(vectors, top_k, nprobe);
   }
 
@@ -356,31 +363,48 @@ class IndexIVFFlat {
       size_t top_k,
       size_t nprobe,
       size_t upper_bound = 0) const {
+    if (!index_) {
+      throw std::runtime_error(
+          "Cannot query_finite_ram() because there is no index.");
+    }
     return index_->query_finite_ram(vectors, top_k, nprobe, upper_bound);
   }
 
   void update(
       const FeatureVectorArray& vectors,
       const std::optional<IdVector>& ids = std::nullopt,
       const std::optional<UpdateOptions>& options = std::nullopt) const {
+    if (!index_) {
+      throw std::runtime_error("Cannot update() because there is no index.");
+    }
     index_->update(vectors, ids, options);
   }
 
   void update(
       const URI& vectors_uri,
       const std::optional<IdVector>& ids = std::nullopt,
       const std::optional<UpdateOptions>& options = std::nullopt) const {
+    if (!index_) {
+      throw std::runtime_error("Cannot update() because there is no index.");
+    }
     index_->update(vectors_uri, ids, options);
   }
 
   void remove(const IdVector& ids) const {
+    if (!index_) {
+      throw std::runtime_error("Cannot remove() because there is no index.");
+    }
     index_->remove(ids);
   }
 
   void write_index(
       const tiledb::Context& ctx,
       const std::string& group_uri,
       bool overwrite = false) const {
+    if (!index_) {
+      throw std::runtime_error(
+          "Cannot write_index() because there is no index.");
+    }
     index_->write_index(ctx, group_uri, overwrite);
   }
 

src/include/api/vamana_index.h

@@ -215,6 +215,9 @@ class IndexVamana {
           datatype_to_string(feature_datatype_) +
           " != " + datatype_to_string(data_set.feature_type()));
     }
+    if (!index_) {
+      throw std::runtime_error("Cannot add() because there is no index.");
+    }
     index_->add(data_set);
   }
 
@@ -223,13 +226,20 @@ class IndexVamana {
       const QueryVectorArray& vectors,
       size_t top_k,
       std::optional<size_t> opt_L = std::nullopt) {
+    if (!index_) {
+      throw std::runtime_error("Cannot query() because there is no index.");
+    }
     return index_->query(vectors, top_k, opt_L);
   }
 
   void write_index(
       const tiledb::Context& ctx,
       const std::string& group_uri,
       bool overwrite = false) const {
+    if (!index_) {
+      throw std::runtime_error(
+          "Cannot write_index() because there is no index.");
+    }
     index_->write_index(ctx, group_uri, overwrite);
   }