fix(ollama): resolve model list loading issue and add Pytest for component testing

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

@@ -1,4 +1,5 @@
 from typing import Any
+from urllib.parse import urljoin
 
 import httpx
 from langchain_community.chat_models import ChatOllama
@@ -41,8 +42,7 @@ def update_build_config(self, build_config: dict, field_value: Any, field_name:
                 base_url_value = self.variables(base_url_value)
             elif not base_url_value:
                 base_url_value = "http://localhost:11434"
-            build_config["model_name"]["options"] = self.get_model(base_url_value + "/api/tags")
-
+            build_config["model_name"]["options"] = self.get_model(base_url_value)
         if field_name == "keep_alive_flag":
             if field_value == "Keep":
                 build_config["keep_alive"]["value"] = "-1"
@@ -55,8 +55,9 @@ def update_build_config(self, build_config: dict, field_value: Any, field_name:
 
         return build_config
 
-    def get_model(self, url: str) -> list[str]:
+    def get_model(self, base_url_value: str) -> list[str]:
         try:
+            url = urljoin(base_url_value, "/api/tags")
             with httpx.Client() as client:
                 response = client.get(url)
                 response.raise_for_status()
@@ -252,6 +253,7 @@ def build_model(self) -> LanguageModel:  # type: ignore[type-var]
         try:
             output = ChatOllama(**llm_params)  # type: ignore
         except Exception as e:
+            print(f"Exception caught: {e}")
             raise ValueError("Could not initialize Ollama LLM.") from e
 
         return output  # type: ignore

src/backend/tests/unit/components/models/test_ChatOllama_component.py

@@ -0,0 +1,131 @@
+import pytest
+from unittest.mock import patch, MagicMock
+from langflow.components.models.OllamaModel import ChatOllamaComponent
+from langchain_community.chat_models.ollama import ChatOllama
+from urllib.parse import urljoin
+
+
+@pytest.fixture
+def component():
+    return ChatOllamaComponent()
+
+
+@patch("httpx.Client.get")
+def test_get_model_success(mock_get, component):
+    mock_response = MagicMock()
+    mock_response.json.return_value = {"models": [{"name": "model1"}, {"name": "model2"}]}
+    mock_response.raise_for_status.return_value = None
+    mock_get.return_value = mock_response
+
+    base_url = "http://localhost:11434"
+
+    model_names = component.get_model(base_url)
+
+    expected_url = urljoin(base_url, "/api/tags")
+
+    mock_get.assert_called_once_with(expected_url)
+
+    assert model_names == ["model1", "model2"]
+
+
+@patch("httpx.Client.get")
+def test_get_model_failure(mock_get, component):
+    # Mock the response for the HTTP GET request to raise an exception
+    mock_get.side_effect = Exception("HTTP request failed")
+
+    url = "http://localhost:11434/api/tags"
+
+    # Assert that the ValueError is raised when an exception occurs
+    with pytest.raises(ValueError, match="Could not retrieve models"):
+        component.get_model(url)
+
+
+def test_update_build_config_mirostat_disabled(component):
+    build_config = {
+        "mirostat_eta": {"advanced": False, "value": 0.1},
+        "mirostat_tau": {"advanced": False, "value": 5},
+    }
+    field_value = "Disabled"
+    field_name = "mirostat"
+
+    updated_config = component.update_build_config(build_config, field_value, field_name)
+
+    assert updated_config["mirostat_eta"]["advanced"] is True
+    assert updated_config["mirostat_tau"]["advanced"] is True
+    assert updated_config["mirostat_eta"]["value"] is None
+    assert updated_config["mirostat_tau"]["value"] is None
+
+
+def test_update_build_config_mirostat_enabled(component):
+    build_config = {
+        "mirostat_eta": {"advanced": False, "value": None},
+        "mirostat_tau": {"advanced": False, "value": None},
+    }
+    field_value = "Mirostat 2.0"
+    field_name = "mirostat"
+
+    updated_config = component.update_build_config(build_config, field_value, field_name)
+
+    assert updated_config["mirostat_eta"]["advanced"] is False
+    assert updated_config["mirostat_tau"]["advanced"] is False
+    assert updated_config["mirostat_eta"]["value"] == 0.2
+    assert updated_config["mirostat_tau"]["value"] == 10
+
+
+@patch("httpx.Client.get")
+def test_update_build_config_model_name(mock_get, component):
+    # Mock the response for the HTTP GET request
+    mock_response = MagicMock()
+    mock_response.json.return_value = {"models": [{"name": "model1"}, {"name": "model2"}]}
+    mock_response.raise_for_status.return_value = None
+    mock_get.return_value = mock_response
+
+    build_config = {
+        "base_url": {"load_from_db": False, "value": None},
+        "model_name": {"options": []},
+    }
+    field_value = None
+    field_name = "model_name"
+
+    updated_config = component.update_build_config(build_config, field_value, field_name)
+
+    assert updated_config["model_name"]["options"] == ["model1", "model2"]
+
+
+def test_update_build_config_keep_alive(component):
+    build_config = {"keep_alive": {"value": None, "advanced": False}}
+    field_value = "Keep"
+    field_name = "keep_alive_flag"
+
+    updated_config = component.update_build_config(build_config, field_value, field_name)
+    assert updated_config["keep_alive"]["value"] == "-1"
+    assert updated_config["keep_alive"]["advanced"] is True
+
+    field_value = "Immediately"
+    updated_config = component.update_build_config(build_config, field_value, field_name)
+    assert updated_config["keep_alive"]["value"] == "0"
+    assert updated_config["keep_alive"]["advanced"] is True
+
+
+@patch(
+    "langchain_community.chat_models.ChatOllama",
+    return_value=ChatOllama(base_url="http://localhost:11434", model="llama3.1"),
+)
+def test_build_model(mock_chat_ollama, component):
+    component.base_url = "http://localhost:11434"
+    component.model_name = "llama3.1"
+    component.mirostat = "Mirostat 2.0"
+    component.mirostat_eta = 0.2  # Ensure this is set as a float
+    component.mirostat_tau = 10.0  # Ensure this is set as a float
+    component.temperature = 0.2
+    component.verbose = True
+    model = component.build_model()
+    assert isinstance(model, ChatOllama)
+    assert model.base_url == "http://localhost:11434"
+    assert model.model == "llama3.1"
+
+
+@patch("langchain_community.chat_models.ChatOllama")
+def test_build_model_failure(mock_chat_ollama, component):
+    # Mock the ChatOllama to raise an exception when initialized
+    pass