Refactor add_llm and add speech to text (#12089)

### What problem does this PR solve?

1. Refactor implementation of add_llm
2. Add speech to text model.

### Type of change

- [x] Refactoring

Signed-off-by: Jin Hai <haijin.chn@gmail.com>

api/apps/llm_app.py

@@ -25,7 +25,7 @@ from api.utils.api_utils import get_allowed_llm_factories, get_data_error_result
 from common.constants import StatusEnum, LLMType
 from api.db.db_models import TenantLLM
 from rag.utils.base64_image import test_image
-from rag.llm import EmbeddingModel, ChatModel, RerankModel, CvModel, TTSModel, OcrModel
+from rag.llm import EmbeddingModel, ChatModel, RerankModel, CvModel, TTSModel, OcrModel, Seq2txtModel
 
 
 @manager.route("/factories", methods=["GET"])  # noqa: F821
@@ -208,33 +208,39 @@ async def add_llm():
     msg = ""
     mdl_nm = llm["llm_name"].split("___")[0]
     extra = {"provider": factory}
-    if llm["model_type"] == LLMType.EMBEDDING.value:
+    model_type = llm["model_type"]
+    model_api_key = llm["api_key"]
+    model_base_url = llm.get("api_base", "")
+    match model_type:
+        case LLMType.EMBEDDING.value:
             assert factory in EmbeddingModel, f"Embedding model from {factory} is not supported yet."
-        mdl = EmbeddingModel[factory](key=llm["api_key"], model_name=mdl_nm, base_url=llm["api_base"])
+            mdl = EmbeddingModel[factory](key=model_api_key, model_name=mdl_nm, base_url=model_base_url)
             try:
                 arr, tc = mdl.encode(["Test if the api key is available"])
                 if len(arr[0]) == 0:
                     raise Exception("Fail")
             except Exception as e:
                 msg += f"\nFail to access embedding model({mdl_nm})." + str(e)
-    elif llm["model_type"] == LLMType.CHAT.value:
+        case LLMType.CHAT.value:
             assert factory in ChatModel, f"Chat model from {factory} is not supported yet."
             mdl = ChatModel[factory](
-            key=llm["api_key"],
+                key=model_api_key,
                 model_name=mdl_nm,
-            base_url=llm["api_base"],
+                base_url=model_base_url,
                 **extra,
             )
             try:
-            m, tc = await mdl.async_chat(None, [{"role": "user", "content": "Hello! How are you doing!"}], {"temperature": 0.9})
+                m, tc = await mdl.async_chat(None, [{"role": "user", "content": "Hello! How are you doing!"}],
+                                             {"temperature": 0.9})
                 if not tc and m.find("**ERROR**:") >= 0:
                     raise Exception(m)
             except Exception as e:
                 msg += f"\nFail to access model({factory}/{mdl_nm})." + str(e)
-    elif llm["model_type"] == LLMType.RERANK:
+
+        case LLMType.RERANK.value:
             assert factory in RerankModel, f"RE-rank model from {factory} is not supported yet."
             try:
-            mdl = RerankModel[factory](key=llm["api_key"], model_name=mdl_nm, base_url=llm["api_base"])
+                mdl = RerankModel[factory](key=model_api_key, model_name=mdl_nm, base_url=model_base_url)
                 arr, tc = mdl.similarity("Hello~ RAGFlower!", ["Hi, there!", "Ohh, my friend!"])
                 if len(arr) == 0:
                     raise Exception("Not known.")
@@ -242,9 +248,10 @@ async def add_llm():
                 msg += f"{factory} dose not support this model({factory}/{mdl_nm})"
             except Exception as e:
                 msg += f"\nFail to access model({factory}/{mdl_nm})." + str(e)
-    elif llm["model_type"] == LLMType.IMAGE2TEXT.value:
+
+        case LLMType.IMAGE2TEXT.value:
             assert factory in CvModel, f"Image to text model from {factory} is not supported yet."
-        mdl = CvModel[factory](key=llm["api_key"], model_name=mdl_nm, base_url=llm["api_base"])
+            mdl = CvModel[factory](key=model_api_key, model_name=mdl_nm, base_url=model_base_url)
             try:
                 image_data = test_image
                 m, tc = mdl.describe(image_data)
@@ -252,26 +259,32 @@ async def add_llm():
                     raise Exception(m)
             except Exception as e:
                 msg += f"\nFail to access model({factory}/{mdl_nm})." + str(e)
-    elif llm["model_type"] == LLMType.TTS:
+        case LLMType.TTS.value:
             assert factory in TTSModel, f"TTS model from {factory} is not supported yet."
-        mdl = TTSModel[factory](key=llm["api_key"], model_name=mdl_nm, base_url=llm["api_base"])
+            mdl = TTSModel[factory](key=model_api_key, model_name=mdl_nm, base_url=model_base_url)
             try:
                 for resp in mdl.tts("Hello~ RAGFlower!"):
                     pass
             except RuntimeError as e:
                 msg += f"\nFail to access model({factory}/{mdl_nm})." + str(e)
-    elif llm["model_type"] == LLMType.OCR.value:
+        case LLMType.OCR.value:
             assert factory in OcrModel, f"OCR model from {factory} is not supported yet."
             try:
-            mdl = OcrModel[factory](key=llm["api_key"], model_name=mdl_nm, base_url=llm.get("api_base", ""))
+                mdl = OcrModel[factory](key=model_api_key, model_name=mdl_nm, base_url=model_base_url)
                 ok, reason = mdl.check_available()
                 if not ok:
                     raise RuntimeError(reason or "Model not available")
             except Exception as e:
                 msg += f"\nFail to access model({factory}/{mdl_nm})." + str(e)
-    else:
+        case LLMType.SPEECH2TEXT:
-        # TODO: check other type of models
+            assert factory in Seq2txtModel, f"Speech model from {factory} is not supported yet."
-        pass
+            try:
+                mdl = Seq2txtModel[factory](key=model_api_key, model_name=mdl_nm, base_url=model_base_url)
+                # TODO: check the availability
+            except Exception as e:
+                msg += f"\nFail to access model({factory}/{mdl_nm})." + str(e)
+        case _:
+            raise RuntimeError(f"Unknown model type: {model_type}")
 
     if msg:
         return get_data_error_result(message=msg)