Move cmd to project root for easier installs (#29)

main.go

@@ -0,0 +1,145 @@
+package main
+
+import (
+	"fmt"
+	"log"
+	"net/url"
+	"os"
+
+	"github.com/amacneil/dbmate/pkg/dbmate"
+	"github.com/joho/godotenv"
+	"github.com/urfave/cli"
+)
+
+func main() {
+	loadDotEnv()
+
+	app := NewApp()
+	err := app.Run(os.Args)
+	if err != nil {
+		fmt.Fprintf(os.Stderr, "Error: %s\n", err)
+		os.Exit(1)
+	}
+}
+
+// NewApp creates a new command line app
+func NewApp() *cli.App {
+	app := cli.NewApp()
+	app.Name = "dbmate"
+	app.Usage = "A lightweight, framework-independent database migration tool."
+	app.Version = dbmate.Version
+
+	app.Flags = []cli.Flag{
+		cli.StringFlag{
+			Name:  "env, e",
+			Value: "DATABASE_URL",
+			Usage: "specify an environment variable containing the database URL",
+		},
+		cli.StringFlag{
+			Name:  "migrations-dir, d",
+			Value: dbmate.DefaultMigrationsDir,
+			Usage: "specify the directory containing migration files",
+		},
+		cli.StringFlag{
+			Name:  "schema-file, s",
+			Value: dbmate.DefaultSchemaFile,
+			Usage: "specify the schema file location",
+		},
+		cli.BoolFlag{
+			Name:  "no-dump-schema",
+			Usage: "don't update the schema file on migrate/rollback",
+		},
+	}
+
+	app.Commands = []cli.Command{
+		{
+			Name:    "new",
+			Aliases: []string{"n"},
+			Usage:   "Generate a new migration file",
+			Action: action(func(db *dbmate.DB, c *cli.Context) error {
+				name := c.Args().First()
+				return db.NewMigration(name)
+			}),
+		},
+		{
+			Name:  "up",
+			Usage: "Create database (if necessary) and migrate to the latest version",
+			Action: action(func(db *dbmate.DB, c *cli.Context) error {
+				return db.CreateAndMigrate()
+			}),
+		},
+		{
+			Name:  "create",
+			Usage: "Create database",
+			Action: action(func(db *dbmate.DB, c *cli.Context) error {
+				return db.Create()
+			}),
+		},
+		{
+			Name:  "drop",
+			Usage: "Drop database (if it exists)",
+			Action: action(func(db *dbmate.DB, c *cli.Context) error {
+				return db.Drop()
+			}),
+		},
+		{
+			Name:  "migrate",
+			Usage: "Migrate to the latest version",
+			Action: action(func(db *dbmate.DB, c *cli.Context) error {
+				return db.Migrate()
+			}),
+		},
+		{
+			Name:    "rollback",
+			Aliases: []string{"down"},
+			Usage:   "Rollback the most recent migration",
+			Action: action(func(db *dbmate.DB, c *cli.Context) error {
+				return db.Rollback()
+			}),
+		},
+		{
+			Name:  "dump",
+			Usage: "Write the database schema to disk",
+			Action: action(func(db *dbmate.DB, c *cli.Context) error {
+				return db.DumpSchema()
+			}),
+		},
+	}
+
+	return app
+}
+
+// load environment variables from .env file
+func loadDotEnv() {
+	if _, err := os.Stat(".env"); err != nil {
+		return
+	}
+
+	if err := godotenv.Load(); err != nil {
+		log.Fatal("Error loading .env file")
+	}
+}
+
+// action wraps a cli.ActionFunc with dbmate initialization logic
+func action(f func(*dbmate.DB, *cli.Context) error) cli.ActionFunc {
+	return func(c *cli.Context) error {
+		u, err := getDatabaseURL(c)
+		if err != nil {
+			return err
+		}
+		db := dbmate.New(u)
+		db.AutoDumpSchema = !c.GlobalBool("no-dump-schema")
+		db.MigrationsDir = c.GlobalString("migrations-dir")
+		db.SchemaFile = c.GlobalString("schema-file")
+
+		return f(db, c)
+	}
+}
+
+// getDatabaseURL returns the current environment database url
+func getDatabaseURL(c *cli.Context) (u *url.URL, err error) {
+	env := c.GlobalString("env")
+	value := os.Getenv(env)
+
+	return url.Parse(value)
+}