pgx

go-pgx

pgx provides helpers for creating/migrating/seeding PostgreSQL database.

Notes

pgx uses golang-migrate/migrate package, which has a bug related with zero migrations. When migrations version in schema_migration table equals 0, it cannot apply or rollback any migrations because it cannot find migration file with version 0.

To avoid this create blank migration with version 0. For example:

000_null.down.sql
000_null.up.sql

Usage

package main

import (
	"io/ioutil"
	"log"

	"github.com/cashwagon/go-pgx"
	"gopkg.in/yaml.v2"
)

type Config = struct {
	DBName         string `yaml:"db_name"`
	User           string `yaml:"user"`
	Password       string `yaml:"password"`
	Host           string `yaml:"host"`
	Port           uint   `yaml:"port"`
	SSLMode        string `yaml:"ssl_mode"`
	ConnectTimeout int    `yaml:"connect_timeout"`
	SSLCert        string `yaml:"ssl_cert"`
	SSLKey         string `yaml:"ssl_key"`
	SSLRootCert    string `yaml:"ssl_root_cert"`
}

func main() {
	options, err := loadOptions("config/config.yaml")
	if err != nil {
		log.Fatal(err)
	}

	log.Println("Creating database...")
	err = pgx.Create(options)
	if err != nil {
		log.Fatal(err)
	}

	log.Println("Migrating database...")
	err = pgx.MigrateUp(options, "db/migrations")
	if err != nil {
		log.Fatal(err)
	}

	log.Println("Seeding database...")
	err = pgx.SeedUp(options, "db/seeds")
	if err != nil {
		log.Fatal(err)
	}

	log.Println("Connecting to database...")
	db, err := pgx.Connect(options)
	if err != nil {
		log.Fatal(err)
	}

	log.Println("Fetching users count...")
	var usersCount int
	err = db.Get(&usersCount, "SELECT count(*) FROM users")
	if err != nil {
		log.Fatal(err)
	}

	log.Printf("Users count: %d\n", usersCount)

	log.Println("Closing database...")
	err = db.Close()
	if err != nil {
		log.Fatal(err)
	}

	log.Printf("Rollback seeds...")
	err = pgx.SeedDown(options, "db/seeds")
	if err != nil {
		log.Fatal(err)
	}

	log.Printf("Rollback migrations...")
	err = pgx.MigrateDown(options, "db/migrations")
	if err != nil {
		log.Fatal(err)
	}

	log.Printf("Dropping database...")
	err = pgx.Drop(options)
	if err != nil {
		log.Fatal(err)
	}
}

func loadOptions(filePath string) (*pgx.Options, error) {
	cfgFile, err := ioutil.ReadFile(filePath)
	if err != nil {
		return nil, err
	}

	var config Config
	err = yaml.Unmarshal(cfgFile, &config)
	if err != nil {
		return nil, err
	}

	return &pgx.Options{
		DBName:          config.DBName,
		User:            config.User,
		Password:        config.Password,
		Host:            config.Host,
		Port:            config.Port,
		SSLMode:         config.SSLMode,
		ConnectTimeout:  config.ConnectTimeout,
		SSLCert:         config.SSLCert,
		SSLKey:          config.SSLKey,
		SSLRootCert:     config.SSLRootCert,
		ConnMaxLifetime: 0,
		MaxOpenConns:    1,
		MaxIdleConns:    0,
	}, nil
}

You can run this example:

cd examples
cp config/config.sample.yaml config/config.yaml
go run main.go

Development

Run Tests

Copy testdata/config/config.sample.yaml to testdata/config/config.yaml.

Edit testdata/config/config.yaml according to your database configuration.

And then:

make test

or

go test -v -cover

Run Linter

make lint

or

golangci-lint run