/**
* ListResources Command
*
* DESIGN PATTERNS:
* - Command pattern with Commander for CLI argument parsing
* - Async/await pattern for asynchronous operations
* - Error handling pattern with try-catch and proper exit codes
*
* CODING STANDARDS:
* - Use async action handlers for asynchronous operations
* - Provide clear option descriptions and default values
* - Handle errors gracefully with process.exit()
* - Log progress and errors to console
* - Use Commander's .option() and .argument() for inputs
*
* AVOID:
* - Synchronous blocking operations in action handlers
* - Missing error handling (always use try-catch)
* - Hardcoded values (use options or environment variables)
* - Not exiting with appropriate exit codes on errors
*/
import { Command } from 'commander';
import { ConfigFetcherService, McpClientManagerService } from '../services';
import type { McpResourceInfo } from '../types';
import { findConfigFile } from '../utils';
interface ListResourcesOptions {
config?: string;
server?: string;
json: boolean;
}
interface ServerResourceResult {
serverName: string;
resources: McpResourceInfo[];
error: unknown;
}
function toErrorMessage(error: unknown): string {
return error instanceof Error ? error.message : String(error);
}
/**
* List all available resources from connected MCP servers
*/
export const listResourcesCommand = new Command('list-resources')
.description('List all available resources from connected MCP servers')
.option('-c, --config <path>', 'Path to MCP server configuration file')
.option('-s, --server <name>', 'Filter by server name')
.option('-j, --json', 'Output as JSON', false)
.action(async (options: ListResourcesOptions): Promise<void> => {
try {
const configFilePath = options.config || findConfigFile();
if (!configFilePath) {
throw new Error('No config file found. Use --config or create mcp-config.yaml');
}
const configFetcher = new ConfigFetcherService({ configFilePath });
const config = await configFetcher.fetchConfiguration();
const clientManager = new McpClientManagerService();
// Connect to all configured MCP servers in parallel
await Promise.all(
Object.entries(config.mcpServers).map(
async ([serverName, serverConfig]): Promise<void> => {
try {
await clientManager.connectToServer(serverName, serverConfig);
if (!options.json) {
console.error(`✓ Connected to ${serverName}`);
}
} catch (error) {
if (!options.json) {
console.error(`✗ Failed to connect to ${serverName}: ${toErrorMessage(error)}`);
}
}
},
),
);
const clients = options.server
? [clientManager.getClient(options.server)].filter(
(c): c is NonNullable<typeof c> => c !== undefined,
)
: clientManager.getAllClients();
if (clients.length === 0) {
throw new Error('No MCP servers connected');
}
// Collect resources from all servers in parallel
const resourcesByServer: Record<string, McpResourceInfo[]> = {};
const resourceResults: ServerResourceResult[] = await Promise.all(
clients.map(async (client): Promise<ServerResourceResult> => {
try {
const resources = await client.listResources();
return { serverName: client.serverName, resources, error: null };
} catch (error) {
const resources: McpResourceInfo[] = [];
return { serverName: client.serverName, resources, error };
}
}),
);
for (const { serverName, resources, error } of resourceResults) {
if (error && !options.json) {
console.error(`Failed to list resources from ${serverName}: ${toErrorMessage(error)}`);
}
resourcesByServer[serverName] = resources;
}
// Output results
if (options.json) {
console.log(JSON.stringify(resourcesByServer, null, 2));
} else {
for (const [serverName, resources] of Object.entries(resourcesByServer)) {
console.log(`\n${serverName}:`);
if (resources.length === 0) {
console.log(' No resources available');
} else {
for (const resource of resources) {
const label = resource.name ? `${resource.name} (${resource.uri})` : resource.uri;
console.log(
` - ${label}${resource.description ? `: ${resource.description}` : ''}`,
);
}
}
}
}
await clientManager.disconnectAll();
} catch (error) {
console.error(`Error executing list-resources: ${toErrorMessage(error)}`);
process.exit(1);
}
});
