Capabilities handling, database.

database/migrations/1_create_users_table.go

@@ -0,0 +1,44 @@
+package migrations
+
+import (
+	// stdlib
+	"database/sql"
+)
+
+// CreateUsersTableUp creates local users table used for authentication.
+func CreateUsersTableUp(tx *sql.Tx) error {
+	if _, err := tx.Exec(`
+	CREATE TABLE users (
+		uuid			UUID NOT NULL,
+		login			TEXT NOT NULL,
+		password_hash	TEXT NOT NULL,
+		password_salt	TEXT NOT NULL,
+		active			BOOLEAN NOT NULL DEFAULT false,
+		created_at		TIMESTAMP WITH TIME ZONE NOT NULL
+	);
+
+	COMMENT ON COLUMN users.uuid IS 'User UUID';
+	COMMENT ON COLUMN users.login IS 'User login';
+	COMMENT ON COLUMN users.password_hash IS 'Hashed user password';
+	COMMENT ON COLUMN users.password_salt IS 'Salt for user password';
+	COMMENT ON COLUMN users.active IS 'Active user flag. 0 - banned';
+	COMMENT ON COLUMN users.created_at IS 'User registration timestamp';
+
+	CREATE INDEX users_uuid_idx ON users(uuid);
+	CREATE INDEX users_login_idx ON users(login);
+	CREATE INDEX users_created_at_idx ON users(created_at);
+	`); err != nil {
+		return err
+	}
+
+	return nil
+}
+
+// CreateUsersTableDown deletes local users table used for authentication.
+func CreateUsersTableDown(tx *sql.Tx) error {
+	if _, err := tx.Exec(`DROP TABLE users;`); err != nil {
+		return err
+	}
+
+	return nil
+}

database/migrations/exported.go

@@ -0,0 +1,81 @@
+package migrations
+
+import (
+	// stdlib
+	"database/sql"
+	"log"
+	"os"
+	"strconv"
+
+	// other
+	"github.com/pressly/goose"
+)
+
+func Initialize() {
+	log.Println("Initializing database migrations...")
+
+	_ = goose.SetDialect("postgres")
+
+	goose.AddNamedMigration("1_create_users_table.go", CreateUsersTableUp, CreateUsersTableDown)
+
+	// Migrations should be registered here.
+}
+
+func Migrate(db *sql.DB) {
+	log.Println("Starting database migration procedure...")
+
+	// Prepare migrations configuration.
+	var action = "UP"
+	actionFromEnv, actionFound := os.LookupEnv("DATABASE_ACTION")
+	if actionFound {
+		log.Println("Migration action override: " + actionFromEnv)
+		action = actionFromEnv
+	} else {
+		log.Println("Executing default migration action (UP)")
+	}
+
+	var count int64
+	countFromEnv, countFound := os.LookupEnv("DATABASE_COUNT")
+	if countFound {
+		log.Println("Migration count override: " + countFromEnv)
+		countAsInt, err := strconv.ParseInt(countFromEnv, 10, 64)
+		if err != nil {
+			log.Fatalln("Failed to convert count gathered from DATABASE_COUNT to integer")
+		}
+		count = countAsInt
+	} else {
+		log.Println("Applying or rollback this count of migrations: " + countFromEnv + ". 0 - all.")
+	}
+
+	// Execute migrations.
+	var err error
+	currentDBVersion, gooseerr := goose.GetDBVersion(db)
+	if gooseerr != nil {
+		log.Fatalln("Failed to get database version: " + gooseerr.Error())
+	}
+	log.Println("Current database version obtained: " + strconv.Itoa(int(currentDBVersion)))
+	if action == "UP" && count == 0 {
+		log.Println("Applying all unapplied migrations...")
+		err = goose.Up(db, ".")
+	} else if action == "UP" && count != 0 {
+		newVersion := currentDBVersion + count
+		log.Println("Migrating database to specific version: " + strconv.Itoa(int(newVersion)))
+		err = goose.UpTo(db, ".", newVersion)
+	} else if action == "DOWN" && count == 0 {
+		log.Println("Downgrading database to zero state, you'll need to re-apply migrations!")
+		err = goose.Down(db, ".")
+		log.Fatalln("Database downgraded to zero state. You have to re-apply migrations")
+	} else if action == "DOWN" && count != 0 {
+		newVersion := currentDBVersion - count
+		log.Println("Downgrading database to specific version: " + strconv.Itoa(int(newVersion)))
+		err = goose.DownTo(db, ".", newVersion)
+	} else {
+		log.Fatalln("Unsupported set of migration parameters, cannot continue: " + action + "/" + countFromEnv)
+	}
+
+	if err != nil {
+		log.Fatalln("Failed to execute migration sequence: " + err.Error())
+	}
+
+	log.Println("Database migrated successfully")
+}