add all wrapped indexes to the index_read

Summary:
These were not added in the refactoring, so adding them now.

Added unit tests which should cover things

The `orig->own_fields = false` because we wrap the inner index too, so it gets deleted.

Reviewed By: bshethmeta, pankajsingh88

Differential Revision: D64702824

fbshipit-source-id: b2e36374dd0066581c57a55b0ea16323cdc519f0

faiss/cppcontrib/factory_tools.cpp

@@ -144,6 +144,10 @@ std::string reverse_index_factory(const faiss::Index* index) {
             const faiss::IndexScalarQuantizer* sq_index =
                     dynamic_cast<const faiss::IndexScalarQuantizer*>(index)) {
         return std::string("SQ") + sq_types.at(sq_index->sq.qtype);
+    } else if (
+            const faiss::IndexIDMap* idmap =
+                    dynamic_cast<const faiss::IndexIDMap*>(index)) {
+        return std::string("IDMap,") + reverse_index_factory(idmap->index);
     }
     // Avoid runtime error, just return empty string for logging.
     return "";

faiss/cppcontrib/factory_tools.h

@@ -10,6 +10,7 @@
 #pragma once
 
 #include <faiss/IndexHNSW.h>
+#include <faiss/IndexIDMap.h>
 #include <faiss/IndexIVFFlat.h>
 #include <faiss/IndexIVFPQFastScan.h>
 #include <faiss/IndexLSH.h>