redis_tool.ts•6.52 kB
import { Redis } from 'ioredis';
let redisClient: Redis | null = null;
/**
* Gets a Redis client instance, creating one if necessary.
* This handles initial connection and reconnection after a tool reload.
* @returns {Redis} An active ioredis client instance.
*/
function getClient(): Redis {
const redisUri = process.env.REDIS_URI;
if (!redisUri) {
throw new Error("REDIS_URI environment variable is not set.");
}
// If client is null or has been disconnected (status 'end'), create a new one.
if (redisClient === null || redisClient.status === 'end') {
redisClient = new Redis(redisUri, {
retryStrategy: times => Math.min(times * 50, 2000),
maxRetriesPerRequest: 3,
enableOfflineQueue: true,
enableReadyCheck: true,
connectTimeout: 5000,
});
}
return redisClient;
}
/**
* A set of dangerous Redis commands that are blocked from execution.
*/
const DANGEROUS_COMMANDS = new Set([
'FLUSHALL', 'FLUSHDB', 'KEYS', 'SHUTDOWN', 'CONFIG',
'SCRIPT', 'EVAL', 'EVALSHA', 'SAVE', 'BGSAVE', 'SLAVEOF'
]);
/** Parameter list for the redis_tool */
export const schema = {
name: "redis_tool",
description: "执行 Redis 命令，支持字符串、哈希、列表、集合等多种数据结构。",
type: "object",
properties: {
command: {
type: "string",
description: "要执行的 Redis 命令 (例如, 'GET', 'SET')",
},
args: {
type: "array",
description: "命令的参数列表 (例如: [\"mykey\", \"myvalue\"])",
items: {
type: "string"
},
default: []
},
},
required: ["command"]
};
export default async (request: any) => {
try {
const command = String(request.params.arguments?.command).toUpperCase();
const args = request.params.arguments?.args || [];
if (DANGEROUS_COMMANDS.has(command)) {
return {
content: [{
type: "text",
text: JSON.stringify({
error: "Execution of dangerous command is denied.",
command: command,
hint: `The command '${command}' is on the denylist for security reasons.`
}, null, 2),
}],
isError: true,
};
}
if (!Array.isArray(args)) {
return {
content: [{
type: "text",
text: JSON.stringify({
error: "Invalid parameter type for 'args'",
hint: "'args' must be an array of strings. For example: [\"key\", \"value\"]"
}, null, 2),
}],
isError: true,
};
}
const client = getClient();
const results = await client.call(command, ...args);
const formattedResults = formatRedisResults(command, results);
return {
content: [{
type: "text",
text: JSON.stringify(formattedResults, null, 2),
}],
};
} catch (error: any) {
const command = request.params.arguments?.command || 'UNKNOWN';
const args = request.params.arguments?.args || [];
const errorResponse = {
error: {
code: error.code || error.name || "REDIS_ERROR",
message: error.message,
},
command: command,
args: args,
hint: getErrorHint(command, error.message)
};
return {
content: [{
type: "text",
text: JSON.stringify(errorResponse, null, 2),
}],
isError: true,
};
}
};
/**
* Formats Redis results based on command type for improved readability
*/
function formatRedisResults(command: string, results: any): any {
if (results === null) {
return { result: null };
}
if (Array.isArray(results) && command.toUpperCase() === 'HGETALL') {
const obj: Record<string, any> = {};
for (let i = 0; i < results.length; i += 2) {
if (i + 1 < results.length) {
obj[results[i]] = results[i + 1];
}
}
return obj;
}
if (Buffer.isBuffer(results)) {
return results.toString();
}
return results;
}
/**
* Provides helpful hints for common Redis errors
*/
function getErrorHint(command: string, errorMessage: string): string {
const upperCaseCommand = command.toUpperCase();
if (errorMessage.includes("wrong number of arguments")) {
return getCommandSyntaxHint(upperCaseCommand);
}
if (errorMessage.includes("WRONGTYPE")) {
return "The data type of the key does not match the requested command operation.";
}
if (errorMessage.includes("no such key")) {
return "The specified key does not exist.";
}
return "Please check the command syntax and parameters.";
}
/**
* Provides syntax hints for common Redis commands
*/
function getCommandSyntaxHint(command: string): string {
const syntaxMap: Record<string, string> = {
'GET': 'GET key',
'SET': 'SET key value [EX seconds] [PX milliseconds] [NX|XX]',
'HGET': 'HGET key field',
'HSET': 'HSET key field value [field value ...]',
'HGETALL': 'HGETALL key',
'LPUSH': 'LPUSH key element [element ...]',
'RPUSH': 'RPUSH key element [element ...]',
'LRANGE': 'LRANGE key start stop',
'SADD': 'SADD key member [member ...]',
'SMEMBERS': 'SMEMBERS key',
'ZADD': 'ZADD key score member [score member ...]',
'ZRANGE': 'ZRANGE key start stop [WITHSCORES]',
'DEL': 'DEL key [key ...]',
'EXISTS': 'EXISTS key [key ...]',
'EXPIRE': 'EXPIRE key seconds',
'TTL': 'TTL key',
'INCR': 'INCR key',
'DECR': 'DECR key',
};
return syntaxMap[command] || `Please consult the Redis documentation for the syntax of ${command}.`;
}
// Destroy function
export async function destroy() {
console.log("Destroy redis_tool");
if (redisClient) {
try {
// Forcefully disconnect for tool reloads
redisClient.disconnect();
} catch (error: any) {
console.error("Force disconnect error:", error.message);
}
}
}