I have a microservice A that Im currnetly testing and in this microservice, it sends api requests to another microservice B that I have. My question is: how can I run that other microservce B in my global-setup.js in order for it to start running before I run my jest tests for microservice A
#How to run a command to start server in different folder
knotty fable
knotty fable
yes
ionic quail
Is it an async capable file?
knotty fable
/* eslint-disable */
var __TEARDOWN_MESSAGE__: string;
module.exports = async function () {
// Start services that that the app needs to run (e.g. database, docker-compose, etc.).
console.log('\nSetting up...\n');
// Hint: Use `globalThis` to pass variables to global teardown.
globalThis.__TEARDOWN_MESSAGE__ = '\nTearing down...\n';
};
i am working in an nx workspace
ionic quail
oh its CJS
nx?
CJS modules have to resolve immediately, so you can't wait thre
you might have to wait in a test instead
knotty fable
nx?
monorepo
thats just the file that was auto generated when i created the nx workspace. So I'm guessig they want me to start services inside this file
ionic quail
Yeah but you cannot wait inside a CJS module, they are syncronous
So you either need a testing framework that uses ESM or has an async compatible startup, like it imports a function and waits for it. Or you need to wait for A to be ready in your async tests.
Maybe Jest has async setup
Oh!
yeah it's exporting a function, so you're good.
So in that case I would just return a Promise that pings server A until it's ready
ionic quail
What do you mean?
knotty fable
npx nx run treasury-microservice:serve
This is the command i use to start that microservice
ionic quail
You probably want to use spawn to run a command
knotty fable
I've tried but it keeps throwing errors
ionic quail
import { spawn, SpawnOptionsWithoutStdio } from 'child_process'
import { ArrayMinLength } from '../types/helpers.js'
export function spawnShellCommand(command: string, extras: SpawnOptionsWithoutStdio) {
const parts = command.split(' ') as ArrayMinLength<string, 1> // eslint-disable-line no-type-assertion/no-type-assertion -- split returns an array of length at least 1
// if (process.platform === 'win32') {
// parts[0] += '.cmd'
// }
const options = {
shell: true,
...extras
}
return spawn(parts[0], parts.slice(1), options)
}
export type TupleOfLength<T, N extends number, Acc extends T[] = []> = Acc['length'] extends N ? Acc : TupleOfLength<T, N, [...Acc, T]>;
export type ArrayMinLength<T, N extends number> = [...TupleOfLength<T, N>, ...T[]];
const command = 'my command'
const service = spawnShellCommand(command, {
//cwd: theDir
})
ok ill give it a go
ionic quail
You can write it differently, but that's the function and helper types I use to make it nice.
// if (process.platform === 'win32') {
// parts[0] += '.cmd'
// }
This used to be needed on windows, but seems not now. Probably its only needed on older version of node.
knotty fable
Great it works
ionic quail
Cool
knotty fable
thanks so much. been stuck on that for ages
ionic quail
Are you able to wait for it to start OK?
You can either ping it in a promise, or just for the spawn to give you a certain output that indicates it's ready.
knotty fable
I mean a work around could be to just set a delay of 10s and then proceed right?
ionic quail
In your setup function
return new Promise<boolean>( (resolve, reject) => {
const service = spawnShellCommand(command, { cwd: foo })
service.on('data', (data: string) => {
if (data.includes('Service Ready') resolve(true)
})
}
You could add a timer to resolves with false, or rejects, after a period of time. But something like that should be good enough.
I didn't test that, data might be a buffer or something, but I think you can work it out
If it's a Buffer, you can probably just to data.toString()
knotty fable
Perfect thank you