Postgre "too many clients already" on running tests

[mariomka]

• Laravel Version: 5.4.12
• PHP Version: PHP 7.1.0-2+deb.sury.org~xenial+1 (cli) ( NTS )
• Database Driver & Version: psql (PostgreSQL) 9.5.5

(Running on Homestead)

Description:

On running more than 100 tests that use DatabaseMigrations the following error appears:

Illuminate\Database\QueryException: SQLSTATE[08006] [7] FATAL:  sorry, too many clients already

Steps To Reproduce:

Run more than 100 tests (methods) using DatabaseMigrations on Postgree (default max connections is 100).

I have created a repository to ease reproduce it: https://github.com/mariomka/laravel-pgsql-too-many-clients-test

• git clone https://github.com/mariomka/laravel-pgsql-too-many-clients-test.git
• composer install
• php vendor/bin/homestead make
• vagrant up
• vagrant ssh
• cd laravel-pgsql-too-many-clients-test
• ./vendor/bin/phpunit

While tests are running you can see Postgre connections count with:

select count(*) from pg_stat_activity;

Or full info with:

select * from pg_stat_activity;

[apstyx]

I am experiencing the same error with one difference, not making use of DatabaseMigrations in my tests.

[wins1908]

I have the fix for lumen above

[wins1908]

here is PR for Laravel #18752

[RobvH]

Yep, same here, see my post on the PR for details.

[mfn]

I believe this was fixed (for Laravel) in 5.5 and at least backported to 5.4 (or it was introduced in 5.4, don't remember); I know this issue well because I had the same problem in the past.

It's all connected to this trait \Illuminate\Foundation\Testing\DatabaseTransactions.

See the code in 5.3:

    public function beginDatabaseTransaction()
    {
        $database = $this->app->make('db');

        foreach ($this->connectionsToTransact() as $name) {
            $database->connection($name)->beginTransaction();
        }

        $this->beforeApplicationDestroyed(function () use ($database) {
            foreach ($this->connectionsToTransact() as $name) {
                $database->connection($name)->rollBack();
            }
        });
    }

Now compare it to 5.4/5.5

    public function beginDatabaseTransaction()
    {
        $database = $this->app->make('db');

        foreach ($this->connectionsToTransact() as $name) {
            $database->connection($name)->beginTransaction();
        }

        $this->beforeApplicationDestroyed(function () use ($database) {
            foreach ($this->connectionsToTransact() as $name) {
                $connection = $database->connection($name);

                $connection->rollBack();
                $connection->disconnect();
            }
        });
    }

This contains the needed ->disconect() call.

It works for us (we've >2k tests, lots of them using this trait) and before this fix I basically had a copy of the trait doing exactly this and could remove it once we upgraded to 5.4/5.5