execute_k6_test
Run load tests to evaluate system performance by executing k6 scripts with configurable duration and virtual user simulation.
Instructions
Execute a k6 load test.
Args: script_file: Path to the k6 test script (.js) duration: Duration of the test (e.g., "30s", "1m", "5m") vus: Number of virtual users to simulate
Input Schema
TableJSON Schema
| Name | Required | Description | Default |
|---|---|---|---|
| script_file | Yes | ||
| duration | No | 30s | |
| vus | No |
Implementation Reference
- k6_server.py:69-78 (handler)The handler function for the 'execute_k6_test' MCP tool, decorated with @mcp.tool() for automatic registration and handling tool execution by delegating to the run_k6_script helper.
async def execute_k6_test(script_file: str, duration: str = "30s", vus: int = 10) -> str: """Execute a k6 load test. Args: script_file: Path to the k6 test script (.js) duration: Duration of the test (e.g., "30s", "1m", "5m") vus: Number of virtual users to simulate """ return await run_k6_script(script_file, duration, vus) - k6_server.py:14-67 (helper)Supporting utility function that implements the core logic for running k6 tests via subprocess, including file validation, command construction, execution, and error handling.
async def run_k6_script(script_file: str, duration: str = "30s", vus: int = 10) -> str: """Run a k6 load test script. Args: script_file: Path to the k6 test script (.js) duration: Duration of the test (e.g., "30s", "1m", "5m") vus: Number of virtual users to simulate Returns: str: k6 execution output """ try: # Convert to absolute path script_file_path = Path(script_file).resolve() # Validate file exists and is a .js file if not script_file_path.exists(): return f"Error: Script file not found: {script_file}" if not script_file_path.suffix == '.js': return f"Error: Invalid file type. Expected .js file: {script_file}" # Get k6 binary path from environment k6_bin = os.getenv('K6_BIN', 'k6') # Print the k6 binary path for debugging print(f"k6 binary path: {k6_bin}") # Build command cmd = [str(Path(k6_bin).resolve())] cmd.extend(['run']) cmd.extend(['-d', duration]) cmd.extend(['-u', str(vus)]) cmd.extend([str(script_file_path)]) # Print the full command for debugging print(f"Executing command: {' '.join(cmd)}") # Run the command and capture output result = subprocess.run(cmd, capture_output=True, text=True) # Print output for debugging print(f"\nCommand output:") print(f"Return code: {result.returncode}") print(f"Stdout: {result.stdout}") print(f"Stderr: {result.stderr}") if result.returncode != 0: return f"Error executing k6 test:\n{result.stderr}" return result.stdout except Exception as e: return f"Unexpected error: {str(e)}"