refactor: Update OllamaModel.py to include new features and improve build configuration

src/backend/base/langflow/components/models/OllamaModel.py

@@ -1,9 +1,13 @@
-from langchain_community.chat_models import ChatOllama
-from langchain_core.language_models.chat_models import BaseChatModel
+from typing import Any
 
+import httpx
+from langchain_community.chat_models import ChatOllama
+
+from langflow.base.constants import STREAM_INFO_TEXT
 from langflow.base.models.model import LCModelComponent
-from langflow.field_typing import LanguageModel, Text
-from langflow.io import BoolInput, DictInput, DropdownInput, FloatInput, IntInput, Output, StrInput
+from langflow.field_typing import LanguageModel
+from langflow.io import BoolInput, DictInput, DropdownInput, FloatInput, IntInput, MessageInput, Output, StrInput
+from langflow.schema.message import Message
 
 
 class ChatOllamaComponent(LCModelComponent):
@@ -11,24 +15,77 @@ class ChatOllamaComponent(LCModelComponent):
     description = "Generate text using Ollama Local LLMs."
     icon = "Ollama"
 
+    def update_build_config(self, build_config: dict, field_value: Any, field_name: str | None = None):
+        if field_name == "mirostat":
+            if field_value == "Disabled":
+                build_config["mirostat_eta"]["advanced"] = True
+                build_config["mirostat_tau"]["advanced"] = True
+                build_config["mirostat_eta"]["value"] = None
+                build_config["mirostat_tau"]["value"] = None
+
+            else:
+                build_config["mirostat_eta"]["advanced"] = False
+                build_config["mirostat_tau"]["advanced"] = False
+
+                if field_value == "Mirostat 2.0":
+                    build_config["mirostat_eta"]["value"] = 0.2
+                    build_config["mirostat_tau"]["value"] = 10
+                else:
+                    build_config["mirostat_eta"]["value"] = 0.1
+                    build_config["mirostat_tau"]["value"] = 5
+
+        if field_name == "model":
+            base_url_dict = build_config.get("base_url", {})
+            base_url_load_from_db = base_url_dict.get("load_from_db", False)
+            base_url_value = base_url_dict.get("value")
+            if base_url_load_from_db:
+                base_url_value = self.variables(base_url_value)
+            elif not base_url_value:
+                base_url_value = "http://localhost:11434"
+            build_config["model"]["options"] = self.get_model(base_url_value + "/api/tags")
+
+        if field_name == "keep_alive_flag":
+            if field_value == "Keep":
+                build_config["keep_alive"]["value"] = "-1"
+                build_config["keep_alive"]["advanced"] = True
+            elif field_value == "Immediately":
+                build_config["keep_alive"]["value"] = "0"
+                build_config["keep_alive"]["advanced"] = True
+            else:
+                build_config["keep_alive"]["advanced"] = False
+
+        return build_config
+
+    def get_model(self, url: str) -> list[str]:
+        try:
+            with httpx.Client() as client:
+                response = client.get(url)
+                response.raise_for_status()
+                data = response.json()
+
+                model_names = [model["name"] for model in data.get("models", [])]
+                return model_names
+        except Exception as e:
+            raise ValueError("Could not retrieve models. Please, make sure Ollama is running.") from e
+
     inputs = [
         StrInput(
             name="base_url",
             display_name="Base URL",
             info="Endpoint of the Ollama API. Defaults to 'http://localhost:11434' if not specified.",
-            advanced=True,
             value="http://localhost:11434",
         ),
-        StrInput(
+        DropdownInput(
             name="model",
             display_name="Model Name",
             value="llama2",
             info="Refer to https://ollama.ai/library for more models.",
+            refresh_button=True,
         ),
         FloatInput(
             name="temperature",
             display_name="Temperature",
-            value=0.8,
+            value=0.2,
             info="Controls the creativity of model responses.",
         ),
         StrInput(
@@ -146,10 +203,9 @@ class ChatOllamaComponent(LCModelComponent):
             info="Template to use for generating text.",
             advanced=True,
         ),
-        StrInput(
+        MessageInput(
             name="input_value",
             display_name="Input",
-            input_types=["Text", "Data", "Prompt"],
         ),
         BoolInput(
             name="stream",
@@ -168,7 +224,7 @@ class ChatOllamaComponent(LCModelComponent):
         Output(display_name="Language Model", name="model_output", method="build_model"),
     ]
 
-    def text_response(self) -> Text:
+    def text_response(self) -> Message:
         input_value = self.input_value
         stream = self.stream
         system_message = self.system_message
@@ -177,7 +233,7 @@ class ChatOllamaComponent(LCModelComponent):
         self.status = result
         return result
 
-    def build_model(self) -> LanguageModel | BaseChatModel:
+    def build_model(self) -> LanguageModel:
         # Mapping mirostat settings to their corresponding values
         mirostat_options = {"Mirostat": 1, "Mirostat 2.0": 2}