raft-config is idempotent no matter RAFT_COMPILE_LIBRARIES value (#516)

This allows us to correctly handle raft with and without compiled libraries.

Authors:
  - Robert Maynard (https://github.com/robertmaynard)

Approvers:
  - Corey J. Nolet (https://github.com/cjnolet)

URL: #516

cpp/CMakeLists.txt

@@ -276,13 +276,13 @@ install(TARGETS raft_nn
 if(TARGET raft_distance_lib)
   install(TARGETS raft_distance_lib
           DESTINATION ${lib_dir}
-          EXPORT raft-distance-exports)
+          EXPORT raft-distance-lib-exports)
 endif()
 
 if(TARGET raft_nn_lib)
   install(TARGETS raft_nn_lib
           DESTINATION ${lib_dir}
-          EXPORT raft-nn-exports)
+          EXPORT raft-nn-lib-exports)
 endif()
 
 
@@ -364,6 +364,12 @@ raft_export(BUILD raft
 include("${rapids-cmake-dir}/export/write_dependencies.cmake")
 
 set(raft_components distance nn)
+if(TARGET raft_distance_lib)
+  list(APPEND raft_components distance-lib)
+endif()
+if(TARGET raft_nn_lib)
+  list(APPEND raft_components  nn-lib)
+endif()
 foreach(comp IN LISTS raft_components)
   install(
     EXPORT raft-${comp}-exports

cpp/cmake/modules/config.cmake.in

@@ -40,7 +40,8 @@ foreach(lang IN LISTS rapids_global_languages)
 endforeach()
 unset(rapids_global_languages)
 
-set(rapids_allowed_components @RAPIDS_COMPONENTS@)
+set(rapids_base_components @RAPIDS_COMPONENTS@)
+set(rapids_allowed_components ${rapids_base_components})
 
 if(EXISTS "${CMAKE_CURRENT_LIST_DIR}/@[email protected]")
   include("${CMAKE_CURRENT_LIST_DIR}/@[email protected]")
@@ -50,6 +51,7 @@ foreach(comp IN LISTS rapids_allowed_components)
   # this way if a dependency can't be found we fail
   if(${comp} IN_LIST @project_name@_FIND_COMPONENTS)
     include("${CMAKE_CURRENT_LIST_DIR}/@project_name@-${comp}-dependencies.cmake" OPTIONAL)
+    include("${CMAKE_CURRENT_LIST_DIR}/@project_name@-${comp}-lib-dependencies.cmake" OPTIONAL)
   endif()
 endforeach()
 
@@ -58,6 +60,7 @@ include("${CMAKE_CURRENT_LIST_DIR}/@[email protected]" OPTIONAL)
 foreach(comp IN LISTS rapids_allowed_components)
   if(${comp} IN_LIST @project_name@_FIND_COMPONENTS)
     include("${CMAKE_CURRENT_LIST_DIR}/@project_name@-${comp}-targets.cmake" OPTIONAL)
+    include("${CMAKE_CURRENT_LIST_DIR}/@project_name@-${comp}-lib-targets.cmake" OPTIONAL)
     set(@project_name@_${comp}_FOUND TRUE)
   endif()
 endforeach()

cpp/cmake/thirdparty/get_faiss.cmake

@@ -59,8 +59,8 @@ function(find_and_configure_faiss)
 
     # We generate the faiss-config files when we built faiss locally, so always do `find_dependency`
     rapids_export_package(BUILD OpenMP raft-nn-exports) # faiss uses openMP but doesn't export a need for it
-    rapids_export_package(BUILD faiss raft-nn-exports)
-    rapids_export_package(INSTALL faiss raft-nn-exports)
+    rapids_export_package(BUILD faiss raft-nn-exports GLOBAL_TARGETS faiss::faiss faiss)
+    rapids_export_package(INSTALL faiss raft-nn-exports GLOBAL_TARGETS faiss::faiss faiss)
 
     # Tell cmake where it can find the generated faiss-config.cmake we wrote.
     include("${rapids-cmake-dir}/export/find_package_root.cmake")