github.com/pyroscope-io/pyroscope@v0.37.3-0.20230725203016-5f6947968bd0/pkg/sqlstore/migrations/migrations.go

package migrations

import (
	"time"

	"github.com/go-gormigrate/gormigrate/v2"
	"gorm.io/gorm"

	"github.com/pyroscope-io/pyroscope/pkg/config"
	"github.com/pyroscope-io/pyroscope/pkg/model"
)

// Migrate executes all migrations UP that did not run yet.
//
//  1. Migrations must be backward compatible and only extend the schema.
//  2. Migration ID must be a unix epoch time in seconds (use 'date +%s').
//  3. Although in the current shape schema downgrades are not supported,
//     Rollback function must be also provided, and migrations must not import
//     any models in order to avoid side effects: instead, the type should be
//     explicitly defined within the migration body.
//  4. Migration code must be tested within the corresponding service package.
//
// A note on schema downgrades (not supported yet):
//
// As long as migrations are backward compatible, support for schema downgrade
// is not required. Once we introduce a breaking change (e.g, change column
// name or modify the data in any way), downgrades must be supported.
//
// The problem is that this requires migrator to know the future schema:
// v0.4.4 can't know which actions should be taken to revert the database from
// v0.4.5, but not vice-versa (unless they use the same source of migration
// scripts). There are some options:
//   - Changes can be reverted with the later version (that is installed before
//     the application downgrade) or with an independent tool – in containerized
//     deployments this can cause significant difficulties.
//   - Store migrations (as raw SQL scripts) in the database itself or elsewhere
//     locally/remotely.
//
// Before we have a very strong reason to perform a schema downgrade or violate
// the schema backward compatibility guaranties, we should follow the basic
// principle: "... to maintain backwards compatibility between the DB and all
// versions of the code currently deployed in production."
// (https://flywaydb.org/documentation/concepts/migrations#important-notes).
// On the other hand, "the lack of an effective rollback script can be a gating
// factor in the integration and deployment process" (Database Reliability
// Engineering by Laine Campbell & Charity Majors).
func Migrate(db *gorm.DB, c *config.Server) error {
	return gormigrate.New(db, gormigrate.DefaultOptions, []*gormigrate.Migration{
		createUserTableMigration(c.Auth.Internal.AdminUser),
		createAPIKeyTableMigration(),
		createAnnotationsTableMigration(),
		addIndexesUniqueTableMigration(),
		createApplicationMetadataTableMigration(),
	}).Migrate()
}

func createUserTableMigration(adminUser config.AdminUser) *gormigrate.Migration {
	type user struct {
		ID                uint       `gorm:"primarykey"`
		Name              string     `gorm:"type:varchar(255);not null;default:null;index:,unique"`
		Email             *string    `gorm:"type:varchar(255);default:null;index:,unique"`
		FullName          *string    `gorm:"type:varchar(255);default:null"`
		PasswordHash      []byte     `gorm:"type:varchar(255);not null;default:null"`
		Role              int        `gorm:"not null;default:null"`
		IsDisabled        *bool      `gorm:"not null;default:false"`
		IsExternal        *bool      `gorm:"not null;default:false"`
		LastSeenAt        *time.Time `gorm:"default:null"`
		PasswordChangedAt time.Time
		CreatedAt         time.Time
		UpdatedAt         time.Time
	}
	return &gormigrate.Migration{
		ID: "1638496809",
		Migrate: func(tx *gorm.DB) error {
			if err := tx.AutoMigrate(&user{}); err != nil {
				return err
			}
			if adminUser.Create {
				return tx.Create(&user{
					Name:              adminUser.Name,
					Email:             model.String(adminUser.Email),
					PasswordHash:      model.MustPasswordHash(adminUser.Password),
					PasswordChangedAt: time.Now(),
					Role:              int(model.AdminRole),
				}).Error
			}
			return nil
		},
		Rollback: func(tx *gorm.DB) error {
			return tx.Migrator().DropTable(&user{})
		},
	}
}

func createAPIKeyTableMigration() *gormigrate.Migration {
	type apiKey struct {
		ID         uint       `gorm:"primarykey"`
		Name       string     `gorm:"type:varchar(255);not null;default:null;index:,unique"`
		Hash       []byte     `gorm:"type:varchar(255);not null;default:null"`
		Role       int        `gorm:"not null;default:null"`
		ExpiresAt  *time.Time `gorm:"default:null"`
		LastSeenAt *time.Time `gorm:"default:null"`
		CreatedAt  time.Time
	}

	return &gormigrate.Migration{
		ID: "1641917891",
		Migrate: func(tx *gorm.DB) error {
			return tx.AutoMigrate(&apiKey{})
		},
		Rollback: func(tx *gorm.DB) error {
			return tx.Migrator().DropTable(&apiKey{})
		},
	}
}

func createAnnotationsTableMigration() *gormigrate.Migration {
	type annotation struct {
		ID        uint      `gorm:"primarykey"`
		AppName   string    `gorm:"not null;default:null"`
		Timestamp time.Time `gorm:"not null;default:null"`
		Content   string    `gorm:"not null;default:null"`
		CreatedAt time.Time
		UpdatedAt time.Time
	}

	return &gormigrate.Migration{
		ID: "1661975049",
		Migrate: func(tx *gorm.DB) error {
			return tx.AutoMigrate(&annotation{})
		},
		Rollback: func(tx *gorm.DB) error {
			return tx.Migrator().DropTable(&annotation{})
		},
	}
}

func addIndexesUniqueTableMigration() *gormigrate.Migration {
	type annotation struct {
		AppName   string    `gorm:"index:idx_appname_timestamp,unique;not null;default:null"`
		Timestamp time.Time `gorm:"index:idx_appname_timestamp,unique;not null;default:null"`
	}

	return &gormigrate.Migration{
		ID: "1663269650",
		Migrate: func(tx *gorm.DB) error {
			return tx.AutoMigrate(&annotation{})
		},
		Rollback: func(tx *gorm.DB) error {
			return tx.Migrator().DropIndex(&annotation{}, "idx_appname_timestamp")
		},
	}
}

func createApplicationMetadataTableMigration() *gormigrate.Migration {
	type applicationMetadata struct {
		ID              uint   `gorm:"primarykey"`
		FQName          string `gorm:"uniqueIndex;not null;default:null"`
		SpyName         string
		SampleRate      uint32
		Units           string
		AggregationType string
		CreatedAt       time.Time
		UpdatedAt       time.Time
	}

	return &gormigrate.Migration{
		ID: "1667213046",
		Migrate: func(tx *gorm.DB) error {
			return tx.AutoMigrate(&applicationMetadata{})
		},
		Rollback: func(tx *gorm.DB) error {
			return tx.Migrator().DropTable(&applicationMetadata{})
		},
	}
}