lance-mcp/dist/tools/documents/aggregate.js

MCP server for interacting with LanceDB database

import { ErrorCode, McpError } from "@modelcontextprotocol/sdk/types.js";
import { client } from "../../mongodb/client.js";
import { BaseTool } from "../base/tool.js";
export class AggregateTool extends BaseTool {
    constructor() {
        super(...arguments);
        this.name = "aggregate";
        this.description = "Execute a MongoDB aggregation pipeline";
        this.inputSchema = {
            type: "object",
            properties: {
                database: {
                    type: "string",
                    description: "Name of the database to use",
                },
                collection: {
                    type: "string",
                    description: "Name of the collection to query",
                },
                pipeline: {
                    type: "string",
                    description: "Aggregation pipeline stages",
                    default: {},
                },
            },
            required: ["database", "collection", "pipeline"],
        };
    }
    parsePipeline(pipeline) {
        try {
            const parsedPipeline = JSON.parse(pipeline);
            if (!Array.isArray(parsedPipeline)) {
                throw new McpError(ErrorCode.InvalidRequest, `Parsed pipeline must be an array, got ${typeof parsedPipeline}`);
            }
            return parsedPipeline;
        }
        catch (error) {
            throw new McpError(ErrorCode.InvalidRequest, `Failed to parse pipeline: ${error.message}`);
        }
    }
    validatePipeline(pipeline) {
        if (!Array.isArray(pipeline)) {
            throw new McpError(ErrorCode.InvalidRequest, `Pipeline must be an array, got ${typeof pipeline}`);
        }
        return pipeline;
    }
    async execute(params) {
        try {
            const database = this.validateDatabase(params.database);
            const collection = this.validateCollection(params.collection);
            const pipeline = this.parsePipeline(params.pipeline);
            const results = await client
                .db(database)
                .collection(collection)
                .aggregate(pipeline).toArray();
            return {
                content: [
                    { type: "text", text: JSON.stringify(results, null, 2) },
                ],
                isError: false,
            };
        }
        catch (error) {
            return this.handleError(error);
        }
    }
}