feat: add get_server_config function with validation

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

src/zzpyjenkins/config.py

@@ -20,3 +20,40 @@ def load_config(config_path: Path) -> dict:
             return tomllib.load(f)
     except tomllib.TOMLDecodeError as e:
         raise ConfigError(f"Invalid TOML syntax: {e}") from e
+
+
+REQUIRED_FIELDS = ["url", "username", "password"]
+
+
+def get_server_config(config: dict, server_name: str) -> tuple[str, str, str]:
+    """Extract server configuration from loaded config.
+
+    Args:
+        config: Loaded config dictionary
+        server_name: Name of server section to use
+
+    Returns:
+        Tuple of (url, username, password)
+
+    Raises:
+        ConfigError: If server not found or missing required fields
+    """
+    if server_name not in config:
+        available = ", ".join(config.keys())
+        raise ConfigError(
+            f"Server '{server_name}' not found. Available servers: {available}"
+        )
+
+    server_config = config[server_name]
+
+    for field in REQUIRED_FIELDS:
+        if field not in server_config:
+            raise ConfigError(
+                f"Missing required field '{field}' in server '{server_name}'"
+            )
+
+    return (
+        server_config["url"],
+        server_config["username"],
+        server_config["password"],
+    )

tests/test_config.py

@@ -5,7 +5,7 @@ import tempfile
 import pytest
 from pathlib import Path
 
-from zzpyjenkins.config import load_config, ConfigError
+from zzpyjenkins.config import load_config, ConfigError, get_server_config
 
 
 def test_load_config_file_not_found():
@@ -27,3 +27,44 @@ def test_load_config_invalid_toml():
         assert "Invalid TOML syntax" in str(exc_info.value)
     finally:
         temp_path.unlink()
+
+
+def test_get_server_config_success():
+    """Test getting a valid server config."""
+    config = {
+        "work": {
+            "url": "https://jenkins.example.com",
+            "username": "user",
+            "password": "pass"
+        }
+    }
+    result = get_server_config(config, "work")
+    assert result == ("https://jenkins.example.com", "user", "pass")
+
+
+def test_get_server_config_not_found():
+    """Test error when server name doesn't exist."""
+    config = {
+        "work": {
+            "url": "https://jenkins.example.com",
+            "username": "user",
+            "password": "pass"
+        }
+    }
+    with pytest.raises(ConfigError) as exc_info:
+        get_server_config(config, "home")
+    assert "Server 'home' not found" in str(exc_info.value)
+    assert "work" in str(exc_info.value)
+
+
+def test_get_server_config_missing_field():
+    """Test error when required field is missing."""
+    config = {
+        "incomplete": {
+            "url": "https://jenkins.example.com",
+            "username": "user"
+        }
+    }
+    with pytest.raises(ConfigError) as exc_info:
+        get_server_config(config, "incomplete")
+    assert "password" in str(exc_info.value)