# VLLM K8s Tests Summary

## Overview
Added comprehensive unit tests for the vllm k8s module that test the core functionality without requiring an actual Kubernetes cluster.

## Tests Added

### 1. `load_deployment_manifest` (existing)
- Basic test that the deployment manifest can be loaded

### 2. `load_deployment_manifest_with_custom_name`
- Verifies that custom deployment names are properly set in the manifest

### 3. `load_deployment_manifest_with_model`
- Tests that the MODEL environment variable is correctly set when a model is specified

### 4. `load_deployment_manifest_with_hf_token`
- Verifies that the HuggingFace token is properly injected into the deployment

### 5. `load_deployment_manifest_with_gpu_count`
- Tests that GPU resource limits are correctly configured based on the requested count

### 6. `load_deployment_manifest_sets_unique_instance_id`
- Ensures each deployment gets a unique UUID for the instance label

### 7. `load_deployment_manifest_updates_labels`
- Verifies that both selector labels and template labels are properly updated with the deployment name and instance ID

### 8. `up_args_builder_defaults`
- Tests that the UpArgsBuilder provides correct default values

### 9. `up_args_builder_custom_values`
- Verifies that all custom values can be set through the builder

### 10. `client` (existing)
- Tests that a Kubernetes client can be created

### 11. `api_creates_namespaced_api`
- Placeholder test for API creation logic

## Test Coverage

The tests cover:
- ✅ Deployment manifest loading and parsing
- ✅ Environment variable injection (MODEL, HF_TOKEN)
- ✅ Resource configuration (GPU limits)
- ✅ Label management (name, instance ID)
- ✅ Builder pattern validation
- ✅ UUID generation for unique instances

## Running the Tests

```bash
cargo test --package spnl --lib k8s::vllm::tests --no-default-features --features k8s
```

## Mock K8s API Tests

Added e2e-style tests using `tower-test` to mock the Kubernetes API, inspired by [kube-rs mock tests](https://github.com/kube-rs/kube/blob/main/kube/src/mock_tests.rs).

### 12. `mock_deployment_create`
- Tests deployment creation against a mock K8s API
- Verifies POST request to the deployments endpoint
- Validates successful deployment creation response

### 13. `mock_deployment_delete`
- Tests deployment deletion using `down_with_client()`
- Verifies DELETE request to the deployments endpoint
- Validates successful deletion status response

### 14. `mock_pod_list`
- Tests pod listing with label selectors
- Verifies GET request to the pods endpoint
- Validates pod list response parsing

## Test Infrastructure

### Mock Test Setup
- **`testcontext()`**: Creates a mock K8s client using `tower-test::mock::pair()`
- **`ApiServerVerifier`**: Handles mock API responses for different scenarios
- **Scenarios**: `DeploymentCreate`, `DeploymentDelete`, `PodList`

### Code Refactoring
To enable mock testing, the following internal functions were added:
- `up_with_client(Client, UpArgs)`: Testable version of `up()` that accepts a client
- `down_with_client(Client, &str, Option<String>)`: Testable version of `down()` that accepts a client

The public `up()` and `down()` functions now delegate to these internal functions after creating a real client.

## Future Enhancements

While the current tests cover manifest generation and basic K8s API interactions, future enhancements could include:

1. **Port Forwarding Tests**: Testing the port forwarding logic with mock connections
2. **Log Streaming Tests**: Testing the log streaming functionality
3. **Error Handling Tests**: Testing various error conditions and edge cases
4. **Complex Scenarios**: Multi-step workflows like deployment updates, scaling, etc.

## Inspiration

These tests were inspired by the kube-rs mock testing patterns, particularly focusing on testing the business logic without requiring a live cluster.