/**
* @fileoverview MCP resource handlers for graph database information.
*
* Provides MCP resources that expose real-time graph database status and schema
* information. Resources are automatically updated and can be subscribed to by
* MCP clients for live monitoring.
*/
import { Effect, pipe, Runtime } from 'effect';
import type { McpServer } from '@modelcontextprotocol/sdk/server/mcp.js';
import { RESOURCE_URIS, MIME_TYPES } from '../constants.js';
import { ERROR_PREFIXES } from '../errors.js';
import { GremlinService } from '../gremlin/service.js';
/**
* Registers MCP resource handlers with the server.
*
* @param server - MCP server instance
* @param runtime - Effect runtime with Gremlin service
*
* Registers resources for:
* - Graph connection status monitoring
* - Live schema information access
*/
export function registerEffectResourceHandlers(
server: McpServer,
runtime: Runtime.Runtime<GremlinService>
): void {
// Register status resource using the recommended registerResource method
server.registerResource(
'status',
RESOURCE_URIS.STATUS,
{
title: 'Gremlin Graph Status',
description: 'Real-time connection status of the Gremlin graph database',
mimeType: MIME_TYPES.TEXT_PLAIN,
},
() =>
Effect.runPromise(
pipe(
GremlinService,
Effect.andThen(service => service.getStatus),
Effect.map(statusObj => statusObj.status),
Effect.catchAll(error => Effect.succeed(`${ERROR_PREFIXES.CONNECTION}: ${error}`)),
Effect.provide(runtime)
)
).then(result => ({
contents: [
{
uri: RESOURCE_URIS.STATUS,
mimeType: MIME_TYPES.TEXT_PLAIN,
text: result,
},
],
}))
);
// Register schema resource using the recommended registerResource method
server.registerResource(
'schema',
RESOURCE_URIS.SCHEMA,
{
title: 'Gremlin Graph Schema',
description:
'Complete schema of the graph including vertex labels, edge labels, and relationship patterns',
mimeType: MIME_TYPES.APPLICATION_JSON,
},
() =>
Effect.runPromise(
pipe(
GremlinService,
Effect.andThen(service => service.getSchema),
Effect.catchAll(error => Effect.succeed({ error: String(error) })),
Effect.provide(runtime)
)
).then(result => ({
contents: [
{
uri: RESOURCE_URIS.SCHEMA,
mimeType: MIME_TYPES.APPLICATION_JSON,
text: JSON.stringify(result, null, 2),
},
],
}))
);
}
