gomigrator
This package contains a very small MySQL migration solution for go written in 1 file.
The aim of this package is to be very small but highly functional.
Roadmap
- Create error variables
- Add testing
- Up/Down functionality
- Whatever issue/idea comes up...
Migration file structure
The migrations are regular SQL files containing sql statements.
The file names need to be structured in the following way:
<version>_<name>.sql
Where the version is always an integer, incremented from the last version.
The name is the name of the migration and preferably describes it.
The name may not contain an underscore (_) character.
Example folder structure:
- migrations/
- 1_create-user-table.sql
- 2_update-email-column.sql
Example migration
Here is a very short migration example, just straight forward SQL like we all know it:
CREATE TABLE user (
id BINARY(16) NOT NULL,
email VARCHAR(255) NOT NULL,
);
ALTER TABLE user ADD CONSTRAINT unique_email UNIQUE(email);
ALTER TABLE user ADD CONSTRAINT pk_user PRIMARY KEY(id);
Usage in an example API
Here is an example of a main file in an API, the essence is shown in the if cfg.Mode == config.MODE_MIGRATE part:
package main
import (
// Golog is a private logging package
"github.com/reefercoding/golog"
// This package
"github.com/reefercoding/gomigrator"
// Example internal packages
"github.com/reefercoding/example-gomigrator/internal/config"
"github.com/reefercoding/example-gomigrator/internal/server"
"github.com/reefercoding/example-gomigrator/internal/storage"
)
func main() {
// Example program config generation
cfg := config.New()
// Create *sql.DB
db, err := storage.NewMysql(&cfg.MySQLConfig)
if err != nil {
golog.Fatalf("could not connect to mysql: %w", err)
}
if cfg.Mode == config.MODE_MIGRATE {
// Stub logger if you like
gomigrator.InfoLogger = golog.Infof
err := gomigrator.Migrate(db, cfg.MigratorDir)
if err != nil {
golog.Fatalf("error occured during gomigrator execution: %w", err)
}
}
if cfg.Mode == config.MODE_API {
s := server.New(cfg, db)
golog.Infof("starting http server on address...")
forever := make(chan bool)
go func() {
if err := http.ListenAndServe(cfg.ListenAddress, s.Router); err != nil {
golog.Fatalf("http server crashed: %w", err)
}
}()
golog.Infof("successfully started http server, listening on: %s", cfg.ListenAddress)
<-forever
}
golog.Infof("exiting application")
}
