PostgreSQL "too many clients already" when running unit tests

[ntokozo-online]

Hi, I'm experiencing the dreaded PostgreSQL Error: sorry, too many clients already error when running unit tests using Vapor 3.

I've configure a job like this:

In the boot file:

import Vapor
import VaporCron

/// Called after your application has initialized.
public func boot(_ app: Application) throws {
    _ = try? VaporCron.schedule(TokenCleanUpJob.self, on: app)
}

TokenCleanUpJob.swift:

import Vapor
import VaporCron
import FluentPostgreSQL

struct TokenCleanUpJob: VaporCronSchedulable {
    static var expression: String {
        return "*/60 * * * *" // Every 60 minutes
    }
    
    static func task(on container: VaporCronContainer) -> Future<Void> {
        return container.withPooledConnection(to: .psql) { connection in
            return Token.query(on: connection)
                .filter(\.expiry < Date())
                .delete()
                .always {
                    try? container.releasePooledConnection(connection, to: .psql)
                }
            }
    }
}

Can you tell me what I am doing wrong? Can this be resolved without having to migrate to Vapor 4?

[MihaelIsaev]

Hey, maybe the problem is with amount of available connections either in pool, or in postgres config itself. I can't remember where to set amount of available connections for pool in Vapor3, but it is set to 1 by default as far as I remember.
If to speak about Vapor4, I'd love to help with transition Vapor3 -> Vapor4, you could write me in Discord to iMike#3049 🙂