feat: Expose gguf model metadata in metadata property

Author: abetlen

llama_cpp/_internals.py

@@ -204,6 +204,31 @@ def detokenize(self, tokens: List[int]) -> bytes:
             output[1:] if len(tokens) > 0 and tokens[0] == self.token_bos() else output
         )
 
+    # Extra
+    def metadata(self) -> Dict[str, str]:
+        assert self.model is not None
+        metadata: Dict[str, str] = {}
+        buffer_size = 1024
+        buffer = ctypes.create_string_buffer(buffer_size)
+        # zero the buffer
+        buffer.value = b'\0' * buffer_size
+        # iterate over model keys
+        for i in range(llama_cpp.llama_model_meta_count(self.model)):
+            nbytes = llama_cpp.llama_model_meta_key_by_index(self.model, i, buffer, buffer_size)
+            if nbytes > buffer_size:
+                buffer_size = nbytes
+                buffer = ctypes.create_string_buffer(buffer_size)
+                nbytes = llama_cpp.llama_model_meta_key_by_index(self.model, i, buffer, buffer_size)
+            key = buffer.value.decode("utf-8")
+            nbytes = llama_cpp.llama_model_meta_val_str_by_index(self.model, i, buffer, buffer_size)
+            if nbytes > buffer_size:
+                buffer_size = nbytes
+                buffer = ctypes.create_string_buffer(buffer_size)
+                nbytes = llama_cpp.llama_model_meta_val_str_by_index(self.model, i, buffer, buffer_size)
+            value = buffer.value.decode("utf-8")
+            metadata[key] = value
+        return metadata
+
     @staticmethod
     def default_params():
         """Get the default llama_model_params."""

llama_cpp/llama.py

@@ -331,6 +331,16 @@ def __init__(
 
         self._mirostat_mu = ctypes.c_float(2.0 * 5.0) # TODO: Move this to sampling context
 
+        try:
+            self.metadata = self._model.metadata()
+        except Exception as e:
+            self.metadata = {}
+            if self.verbose:
+                print(f"Failed to load metadata: {e}", file=sys.stderr)
+        
+        if self.verbose:
+            print(f"Model metadata: {self.metadata}", file=sys.stderr)
+
     @property
     def ctx(self) -> llama_cpp.llama_context_p:
         assert self._ctx.ctx is not None