Embeddings: Migrate and organize Infinity

Use Infinity as a separate backend and handle the model within the
common module. This separates out the embeddings model from the endpoint
which allows for model loading/unloading in core.

Signed-off-by: kingbri <bdashore3@proton.me>

common/model.py

@@ -20,6 +20,15 @@ if not do_export_openapi:
 
     # Global model container
     container: Optional[ExllamaV2Container] = None
+    embeddings_container = None
+
+    # Type hint the infinity emb container if it exists
+    from backends.infinity.model import has_infinity_emb
+
+    if has_infinity_emb:
+        from backends.infinity.model import InfinityContainer
+
+        embeddings_container: Optional[InfinityContainer] = None
 
 
 def load_progress(module, modules):
@@ -100,6 +109,30 @@ async def unload_loras():
     await container.unload(loras_only=True)
 
 
+async def load_embeddings_model(model_path: pathlib.Path, **kwargs):
+    global embeddings_container
+
+    # Break out if infinity isn't installed
+    if not has_infinity_emb:
+        logger.warning(
+            "Skipping embeddings because infinity-emb is not installed.\n"
+            "Please run the following command in your environment "
+            "to install extra packages:\n"
+            "pip install -U .[extras]"
+        )
+        return
+
+    embeddings_container = InfinityContainer(model_path)
+    await embeddings_container.load(**kwargs)
+
+
+async def unload_embeddings_model():
+    global embeddings_container
+
+    await embeddings_container.unload()
+    embeddings_container = None
+
+
 def get_config_default(key, fallback=None, is_draft=False):
     """Fetches a default value from model config if allowed by the user."""
 
@@ -126,3 +159,15 @@ async def check_model_container():
         ).error.message
 
         raise HTTPException(400, error_message)
+
+
+async def check_embeddings_container():
+    """FastAPI depends that checks if an embeddings model is loaded."""
+
+    if embeddings_container is None:
+        error_message = handle_request_error(
+            "No embeddings models are currently loaded.",
+            exc_info=False,
+        ).error.message
+
+        raise HTTPException(400, error_message)