feat: expose the substrait io library as an installable target (#94)

src/substrait/common/CMakeLists.txt

@@ -3,7 +3,7 @@
 add_library(substrait_common Exceptions.cpp)
 target_link_libraries(substrait_common fmt::fmt-header-only)
 
-add_library(substrait_io Io.cpp)
+add_library(substrait_io STATIC Io.cpp)
 add_dependencies(
  substrait_io
  substrait_proto
@@ -12,9 +12,18 @@ add_dependencies(
  fmt::fmt-header-only
  absl::status
  absl::statusor)
+target_include_directories(
+ substrait_io
+ INTERFACE
+ $<BUILD_INTERFACE:${CMAKE_CURRENT_SOURCE_DIR}/../../../include/substrait/common>
+ $<INSTALL_INTERFACE:include/substrait/common>)
 target_link_libraries(substrait_io substrait_proto substrait_textplan_converter
  substrait_textplan_loader absl::status absl::statusor)
 
 if(${SUBSTRAIT_CPP_BUILD_TESTING})
  add_subdirectory(tests)
 endif()
+
+install(TARGETS substrait_io LIBRARY DESTINATION ${CMAKE_INSTALL_LIBDIR})
+install(FILES ../../../include/substrait/common/Io.h
+ DESTINATION "${CMAKE_INSTALL_INCLUDEDIR}/substrait/common")