/nestjs-redis-microservices-close-failure

Primary LanguageJavaScript

Closing Redis Microservice Server Causes Uncaught Error

Problem

When calling app.close() on a redis microservice server, an uncaught error will be thrown.

~/node_modules/.pnpm/ioredis@5.2.2/node_modules/ioredis/built/redis/event_handler.js:182
        self.flushQueue(new Error(utils_1.CONNECTION_CLOSED_ERROR_MSG));
                        ^
Error: Connection is closed.
    at close (~/node_modules/.pnpm/ioredis@5.2.2/node_modules/ioredis/built/redis/event_handler.js:182:25)
    at Socket.<anonymous> (~/node_modules/.pnpm/ioredis@5.2.2/node_modules/ioredis/built/redis/event_handler.js:149:20)
    at Object.onceWrapper (node:events:628:26)
    at Socket.emit (node:events:513:28)
    at TCP.<anonymous> (node:net:757:14)

Expected Behavior

The server closes without any kind of errors on SIGINT or app.close(). I found this during integration testing of my ogma library where I programatically open and close servers to verify an interceptor works as expected.

Reproduction Steps

  1. clone this repo
  2. npm i/yarn/pnpm i
  3. docker compsoe up -d
  4. npm run start:dev/yarn start:dev/pnpm start:dev
  5. observe the error

Possible Solution

The error arises because the server is being clsoed multiple times when app.close() is called. It looks like app.close() ends up calling app.dispose() which calls to the MicroserviceModule.services.close() (pseudocode) which doubles the call to the clsoe method. As ioredis has already closed the conenction, this throws an error.

A solution I played around with locally is to create a protected isClosed variable on the server.ts file in @nestjs/microservices and have all of the server-*.ts files check for this.isClosed before going through the close steps and returning early if it is already closed.