Ubuntu – Failed to connect to PostgreSQL (dial error) in Github Actions

I’m new with Github Actions and Docker. Now I’m trying to set up my first CI and getting this error:

`failed to connect to `host=/var/run/postgresql user= database=`: dial error (dial unix /var/run/postgresql/.s.PGSQL.5432: connect: no such file or directory)`

But locally all works correctly.

My ci.yaml file:

name: CI

on:
  push:
    branches:
      - main
  pull_request:
    branches:
      - main

jobs:
  build:
    runs-on: ubuntu-latest

    services:
      postgres:
        image: postgres:latest
        env:
          POSTGRES_USER: root
          POSTGRES_PASSWORD: password
          POSTGRES_DB: sso_dev
        ports:
          - 5432:5432
        options: >-
          --health-cmd pg_isready
          --health-interval 10s
          --health-timeout 5s
          --health-retries 5

    steps:
      - uses: actions/checkout@v2

      - name: Setup Go
        uses: actions/setup-go@v2
        with:
          go-version: '1.21'

      - name: Install golang-migrate
        run: |
          curl -L https://github.com/golang-migrate/migrate/releases/download/v4.12.2/migrate.linux-amd64.tar.gz | tar xvz
          sudo mv migrate.linux-amd64 /usr/bin/migrate
          which migrate

      - name: Install dependencies
        run: go mod download

      - name: Create /config directory
        run: mkdir -p ./config

      - name: Create .env file
        run: echo "${{ secrets.ENV_CONFIG }}" > ./config/.env

      - name: Display .env file
        run: cat ./config/.env

      - name: Wait for PostgreSQL to be ready
        run: sleep 10

      - name: Check PostgreSQL connection
        run: pg_isready -h localhost -p 5432

      - name: Run tests
        run: make test-all-app

      - name: Notify results
        run: echo "Tests completed!"

In the ENV_CONFIG I have the following env variables:

GRPC_SERVER_PORT=44044
GRPC_SERVER_TIMEOUT=30s

DB_HOST=localhost
DB_PORT=5432
DB_NAME=sso_dev
DB_USER=root
DB_PASSWORD=password
DB_SSL_MODE=disable
DB_CONN_URL="postgres://$DB_USER:$DB_PASSWORD@$DB_HOST:$DB_PORT/$DB_NAME?sslmode=$DB_SSL_MODE"
DB_CONN_POOL_SIZE=10
DB_READ_TIMEOUT=5s
DB_WRITE_TIMEOUT=5s
DB_IDLE_TIMEOUT=60s
DB_DIAL_TIMEOUT=10s

I don’t understand where is the root cause. I asked about it ChatGPT and got the answer that application is attempting to connect to PostgreSQL via a Unix socket, but it can’t find the socket file. But if I’m not mistaken I use tcp connection…

Maybe the reason is the way how I create connection to database in my code (I use Golang)?

package postgres

import (
    "context"
    "fmt"
    "github.com/jackc/pgx/v5/pgxpool"
    _ "github.com/jackc/pgx/v5/stdlib" // Import for side effects
    "github.com/rshelekhov/sso/internal/config"
    "github.com/rshelekhov/sso/internal/storage/postgres/sqlc"
    "net"
)

// NewStorage creates a new Postgres storage
func NewStorage(cfg *config.ServerSettings) (*pgxpool.Pool, error) {
    const method = "storage.postgres.NewStorage"

    poolCfg, err := pgxpool.ParseConfig(cfg.Postgres.ConnURL)
    if err != nil {
        return nil, fmt.Errorf("%s: failed to parse config: %w", method, err)
    }

    poolCfg.MaxConnLifetime = cfg.Postgres.IdleTimeout
    poolCfg.MaxConns = int32(cfg.Postgres.ConnPoolSize)

    dialer := &net.Dialer{KeepAlive: cfg.Postgres.DialTimeout}
    dialer.Timeout = cfg.Postgres.DialTimeout
    poolCfg.ConnConfig.DialFunc = dialer.DialContext

    pool, err := pgxpool.NewWithConfig(context.Background(), poolCfg)
    if err != nil {
        return nil, fmt.Errorf("%s: failed to create pgx connection pool: %w", method, err)
    }

    return pool, nil
}

UPD.

So, I found a way to make this workflow work. I changed ENV_CONFIG secrets a bit, I removed this:

DB_HOST=localhost
DB_PORT=5432
DB_NAME=sso_dev
DB_USER=root
DB_PASSWORD=password
DB_SSL_MODE=disable

And updated this url from:

DB_CONN_URL="postgres://$DB_USER:$DB_PASSWORD@$DB_HOST:$DB_PORT/$DB_NAME?sslmode=$DB_SSL_MODE"

To:

DB_CONN_URL="postgres://root:password@localhost:5432/sso_dev?sslmode=disable"

And it works. For now I’m trying to figure out why compound env variables don’t work