import { readFileSync, existsSync } from "fs";
import { resolve } from "path";
import * as yaml from "js-yaml";
import { SwaggerMCPConfig, validateConfig, SwaggerSource, Config } from "../types/config.js";
import { substituteEnvVarsInObject } from "../utils/env-substitution.js";
const CONFIG_PATH_ENV_VAR = "CONFIG_PATH";
/**
* Gets the configuration file path from environment variable
* @returns The resolved configuration file path
* @throws Error if CONFIG_PATH environment variable is not set
*/
function getConfigPath(): string {
const envConfigPath = process.env[CONFIG_PATH_ENV_VAR];
if (!envConfigPath) {
throw new Error(
`${CONFIG_PATH_ENV_VAR} environment variable is required.\n` +
"Please set CONFIG_PATH to the path of your configuration file."
);
}
// Use the provided path as-is (can be absolute or relative)
return resolve(envConfigPath);
}
/**
* Loads and validates the configuration file
* @returns The validated configuration
* @throws Error if configuration file not found or invalid
*/
export function loadConfig(): Config {
const configPath = getConfigPath();
if (!existsSync(configPath)) {
throw new Error(
`Configuration file not found: ${configPath} (specified via ${CONFIG_PATH_ENV_VAR})\n` +
"Please create the configuration file at the specified path."
);
}
try {
// Read the YAML file
const fileContent = readFileSync(configPath, "utf8");
// Parse YAML
const rawConfig = yaml.load(fileContent);
// Substitute environment variables
const configWithEnvVars = substituteEnvVarsInObject(rawConfig);
// Validate and return
return validateConfig(configWithEnvVars);
} catch (error) {
if (error instanceof yaml.YAMLException) {
throw new Error(`Invalid YAML in configuration file: ${error.message}`);
}
throw error;
}
}
/**
* Detects whether a source is a file or HTTP URL
* @param source The source string
* @returns Object indicating the source type
*/
export function detectSourceType(source: string): {
isHttp: boolean;
isFile: boolean;
protocol?: string;
} {
const httpMatch = source.match(/^(https?):\/\//);
if (httpMatch) {
return {
isHttp: true,
isFile: false,
protocol: httpMatch[1]
};
}
return {
isHttp: false,
isFile: true
};
}
/**
* Enriches the configuration with runtime-detected types
* @param config The validated configuration
* @returns Configuration with runtime-detected types
*/
export function enrichConfigWithTypes(config: Config): SwaggerMCPConfig {
const enrichedSources: SwaggerSource[] = config.sources.map((source) => {
const sourceType = detectSourceType(source.source);
return {
...source,
type: sourceType.isHttp ? "http" : "file"
} as SwaggerSource;
});
return {
...config,
sources: enrichedSources
};
}
/**
* Loads, validates, and enriches the configuration file
* @returns The enriched configuration with runtime types
* @throws Error if configuration file not found or invalid
*/
export function getConfig(): SwaggerMCPConfig {
const config = loadConfig();
return enrichConfigWithTypes(config);
}
