Load the onnxruntime shared lib in python (#731)

.github/workflows/linux-cpu-arm64-build.yml

@@ -59,8 +59,7 @@ jobs:
           mkdir -p ort/lib
           mv microsoft.ml.onnxruntime/**/build/native/include ort/
           mv microsoft.ml.onnxruntime/**/runtimes/linux-arm64/native/* ort/lib/
-          ort_version=$(echo ${{ env.ORT_NIGHTLY_VERSION }} | cut -d- -f1-1)
-          cp ort/lib/libonnxruntime.so ort/lib/libonnxruntime.so.$ort_version
+          cp ort/lib/libonnxruntime.so ort/lib/libonnxruntime.so.1
 
       - name: Download Docker Image
         run: |

.github/workflows/linux-cpu-x64-build.yml

@@ -58,8 +58,7 @@ jobs:
           mkdir -p ort/lib
           mv microsoft.ml.onnxruntime/${{ env.ORT_NIGHTLY_VERSION }}/build/native/include ort/
           mv microsoft.ml.onnxruntime/${{ env.ORT_NIGHTLY_VERSION }}/runtimes/linux-x64/native/* ort/lib/
-          ort_version=$(echo ${{ env.ORT_NIGHTLY_VERSION }} | cut -d- -f1-1)
-          cp ort/lib/libonnxruntime.so ort/lib/libonnxruntime.so.$ort_version
+          cp ort/lib/libonnxruntime.so ort/lib/libonnxruntime.so.1
 
       - name: Build with CMake and GCC
         run: |

.github/workflows/linux-gpu-x64-build.yml

@@ -72,8 +72,7 @@ jobs:
           mkdir -p ort/lib
           mv microsoft.ml.onnxruntime.gpu.linux/${{ env.ORT_NIGHTLY_VERSION }}/buildTransitive/native/include ort/
           mv microsoft.ml.onnxruntime.gpu.linux/${{ env.ORT_NIGHTLY_VERSION }}/runtimes/linux-x64/native/* ort/lib/
-          ort_version=$(echo ${{ env.ORT_NIGHTLY_VERSION }} | cut -d- -f1-1)
-          cp ort/lib/libonnxruntime.so ort/lib/libonnxruntime.so.$ort_version
+          cp ort/lib/libonnxruntime.so ort/lib/libonnxruntime.so.1
 
 
       - name: Get Docker Image

src/models/onnxruntime_api.h

@@ -213,32 +213,7 @@ inline void InitApi() {
 
 #if !defined(__ANDROID__)
   if (ort_lib_handle == nullptr) {
-    const std::array<std::string, 4> target_libraries = {
-        std::string("libonnxruntime.so"),
-        std::string("libonnxruntime.so.1.18.0"),
-        std::string("libonnxruntime.so.1.19.0"),
-        std::string("libonnxruntime.so.1.20.0")};
-
-    // Search parent directory
-    std::string current_module_dir = GetCurrentModuleDir();
-    for (const std::string& lib_name : target_libraries) {
-      std::string pip_path{current_module_dir + "/" + lib_name};
-      ort_lib_handle = LoadDynamicLibraryIfExists(pip_path);
-      if (ort_lib_handle != nullptr) {
-        break;
-      }
-    }
-
-    if (ort_lib_handle == nullptr) {
-      // Search for pip installation
-      for (const std::string& lib_name : target_libraries) {
-        std::string pip_path{current_module_dir + "/../onnxruntime/capi/" + lib_name};
-        ort_lib_handle = LoadDynamicLibraryIfExists(pip_path);
-        if (ort_lib_handle != nullptr) {
-          break;
-        }
-      }
-    }
+    ort_lib_handle = LoadDynamicLibraryIfExists("libonnxruntime.so.1");
   }
 #endif
 

src/python/CMakeLists.txt

@@ -13,9 +13,6 @@ if(NOT (CMAKE_SYSTEM_NAME STREQUAL "Android" OR CMAKE_SYSTEM_NAME STREQUAL "Linu
 target_link_libraries(python PRIVATE ${ONNXRUNTIME_LIB})
 endif()
 
-if(CMAKE_SYSTEM_NAME STREQUAL "Linux")
-  set_property(TARGET python APPEND_STRING PROPERTY LINK_FLAGS " -Xlinker -rpath=\\$ORIGIN/../onnxruntime/capi/")
-endif()
 set_target_properties(python PROPERTIES OUTPUT_NAME "onnxruntime_genai")
 
 if(CMAKE_GENERATOR_TOOLSET MATCHES "Visual Studio")

src/python/py/_dll_directory.py

@@ -8,10 +8,16 @@ def _is_windows():
     return sys.platform.startswith("win")
 
 
+def _is_linux():
+    return sys.platform.startswith("linux")
+
+
 def add_onnxruntime_dependency():
-    """Add the onnxruntime DLL directory to the DLL search path.
+    """Add the onnxruntime shared library dependency.
     
-    This function is a no-op on non-Windows platforms.
+    On Windows, this function adds the onnxruntime DLL directory to the DLL search path.
+    On Linux, this function loads the onnxruntime shared library and its dependencies
+    so that they can be found by the dynamic linker.
     """
     if _is_windows():
         import importlib.util
@@ -20,6 +26,23 @@ def add_onnxruntime_dependency():
             raise ImportError("Could not find the onnxruntime package.")
         ort_package_path = ort_package.submodule_search_locations[0]
         os.add_dll_directory(os.path.join(ort_package_path, "capi"))
+    elif _is_linux():
+        import importlib.util
+        import ctypes
+        import glob
+
+        ort_package = importlib.util.find_spec("onnxruntime")
+        if not ort_package:
+            raise ImportError("Could not find the onnxruntime package.")
+
+        # Load the onnxruntime shared library here since we can find the path in python with ease.
+        # This avoids needing to know the exact path of the shared library from native code.
+        ort_package_path = ort_package.submodule_search_locations[0]
+        ort_lib_path = glob.glob(os.path.join(ort_package_path, "capi", "libonnxruntime.so*"))
+        if not ort_lib_path:
+            raise ImportError("Could not find the onnxruntime shared library.")
+
+        _ = ctypes.CDLL(ort_lib_path[0])
 
 
 def add_cuda_dependency():