Write log lines to DB.Log output (#195)

This makes it possible to redirect the logs somewhere else, useful if you embed dbmate into your application.

pkg/dbmate/db.go

@@ -4,6 +4,7 @@ import (
 	"database/sql"
 	"errors"
 	"fmt"
+	"io"
 	"io/ioutil"
 	"net/url"
 	"os"
@@ -41,6 +42,7 @@ type DB struct {
 	WaitBefore          bool
 	WaitInterval        time.Duration
 	WaitTimeout         time.Duration
+	Log                 io.Writer
 }
 
 // migrationFileRegexp pattern for valid migration files
@@ -63,6 +65,7 @@ func New(databaseURL *url.URL) *DB {
 		WaitBefore:          false,
 		WaitInterval:        DefaultWaitInterval,
 		WaitTimeout:         DefaultWaitTimeout,
+		Log:                 os.Stdout,
 	}
 }
 
@@ -80,6 +83,7 @@ func (db *DB) GetDriver() (Driver, error) {
 	config := DriverConfig{
 		DatabaseURL:         db.DatabaseURL,
 		MigrationsTableName: db.MigrationsTableName,
+		Log:                 db.Log,
 	}
 
 	return driverFunc(config), nil
@@ -104,22 +108,22 @@ func (db *DB) wait(drv Driver) error {
 		return nil
 	}
 
-	fmt.Print("Waiting for database")
+	fmt.Fprint(db.Log, "Waiting for database")
 	for i := 0 * time.Second; i < db.WaitTimeout; i += db.WaitInterval {
-		fmt.Print(".")
+		fmt.Fprint(db.Log, ".")
 		time.Sleep(db.WaitInterval)
 
 		// attempt connection to database server
 		err = drv.Ping()
 		if err == nil {
 			// connection successful
-			fmt.Print("\n")
+			fmt.Fprint(db.Log, "\n")
 			return nil
 		}
 	}
 
 	// if we find outselves here, we could not connect within the timeout
-	fmt.Print("\n")
+	fmt.Fprint(db.Log, "\n")
 	return fmt.Errorf("unable to connect to database: %s", err)
 }
 
@@ -214,7 +218,7 @@ func (db *DB) dumpSchema(drv Driver) error {
 		return err
 	}
 
-	fmt.Printf("Writing: %s\n", db.SchemaFile)
+	fmt.Fprintf(db.Log, "Writing: %s\n", db.SchemaFile)
 
 	// ensure schema directory exists
 	if err = ensureDir(filepath.Dir(db.SchemaFile)); err != nil {
@@ -252,7 +256,7 @@ func (db *DB) NewMigration(name string) error {
 
 	// check file does not already exist
 	path := filepath.Join(db.MigrationsDir, name)
-	fmt.Printf("Creating migration: %s\n", path)
+	fmt.Fprintf(db.Log, "Creating migration: %s\n", path)
 
 	if _, err := os.Stat(path); !os.IsNotExist(err) {
 		return fmt.Errorf("file already exists")
@@ -345,7 +349,7 @@ func (db *DB) migrate(drv Driver) error {
 			continue
 		}
 
-		fmt.Printf("Applying: %s\n", filename)
+		fmt.Fprintf(db.Log, "Applying: %s\n", filename)
 
 		up, _, err := parseMigration(filepath.Join(db.MigrationsDir, filename))
 		if err != nil {
@@ -358,7 +362,7 @@ func (db *DB) migrate(drv Driver) error {
 			if err != nil {
 				return err
 			} else if db.Verbose {
-				printVerbose(result)
+				db.printVerbose(result)
 			}
 
 			// record migration
@@ -386,14 +390,14 @@ func (db *DB) migrate(drv Driver) error {
 	return nil
 }
 
-func printVerbose(result sql.Result) {
+func (db *DB) printVerbose(result sql.Result) {
 	lastInsertID, err := result.LastInsertId()
 	if err == nil {
-		fmt.Printf("Last insert ID: %d\n", lastInsertID)
+		fmt.Fprintf(db.Log, "Last insert ID: %d\n", lastInsertID)
 	}
 	rowsAffected, err := result.RowsAffected()
 	if err == nil {
-		fmt.Printf("Rows affected: %d\n", rowsAffected)
+		fmt.Fprintf(db.Log, "Rows affected: %d\n", rowsAffected)
 	}
 }
 
@@ -485,7 +489,7 @@ func (db *DB) Rollback() error {
 		return err
 	}
 
-	fmt.Printf("Rolling back: %s\n", filename)
+	fmt.Fprintf(db.Log, "Rolling back: %s\n", filename)
 
 	_, down, err := parseMigration(filepath.Join(db.MigrationsDir, filename))
 	if err != nil {
@@ -498,7 +502,7 @@ func (db *DB) Rollback() error {
 		if err != nil {
 			return err
 		} else if db.Verbose {
-			printVerbose(result)
+			db.printVerbose(result)
 		}
 
 		// remove migration record
@@ -548,15 +552,15 @@ func (db *DB) Status(quiet bool) (int, error) {
 			line = fmt.Sprintf("[ ] %s", res.Filename)
 		}
 		if !quiet {
-			fmt.Println(line)
+			fmt.Fprintln(db.Log, line)
 		}
 	}
 
 	totalPending := len(results) - totalApplied
 	if !quiet {
-		fmt.Println()
+		fmt.Fprintln(db.Log)
-		fmt.Printf("Applied: %d\n", totalApplied)
+		fmt.Fprintf(db.Log, "Applied: %d\n", totalApplied)
-		fmt.Printf("Pending: %d\n", totalPending)
+		fmt.Fprintf(db.Log, "Pending: %d\n", totalPending)
 	}
 
 	return totalPending, nil

pkg/dbmate/driver.go

@@ -2,6 +2,7 @@ package dbmate
 
 import (
 	"database/sql"
+	"io"
 	"net/url"
 
 	"github.com/amacneil/dbmate/pkg/dbutil"
@@ -25,6 +26,7 @@ type Driver interface {
 type DriverConfig struct {
 	DatabaseURL         *url.URL
 	MigrationsTableName string
+	Log                 io.Writer
 }
 
 // DriverFunc represents a driver constructor

pkg/driver/clickhouse/clickhouse.go

@@ -4,6 +4,7 @@ import (
 	"bytes"
 	"database/sql"
 	"fmt"
+	"io"
 	"net/url"
 	"regexp"
 	"sort"
@@ -23,6 +24,7 @@ func init() {
 type Driver struct {
 	migrationsTableName string
 	databaseURL         *url.URL
+	log                 io.Writer
 }
 
 // NewDriver initializes the driver
@@ -30,6 +32,7 @@ func NewDriver(config dbmate.DriverConfig) dbmate.Driver {
 	return &Driver{
 		migrationsTableName: config.MigrationsTableName,
 		databaseURL:         config.DatabaseURL,
+		log:                 config.Log,
 	}
 }
 
@@ -108,7 +111,7 @@ func (drv *Driver) quoteIdentifier(str string) string {
 // CreateDatabase creates the specified database
 func (drv *Driver) CreateDatabase() error {
 	name := drv.databaseName()
-	fmt.Printf("Creating: %s\n", name)
+	fmt.Fprintf(drv.log, "Creating: %s\n", name)
 
 	db, err := drv.openClickHouseDB()
 	if err != nil {
@@ -124,7 +127,7 @@ func (drv *Driver) CreateDatabase() error {
 // DropDatabase drops the specified database (if it exists)
 func (drv *Driver) DropDatabase() error {
 	name := drv.databaseName()
-	fmt.Printf("Dropping: %s\n", name)
+	fmt.Fprintf(drv.log, "Dropping: %s\n", name)
 
 	db, err := drv.openClickHouseDB()
 	if err != nil {

pkg/driver/mysql/mysql.go

@@ -4,6 +4,7 @@ import (
 	"bytes"
 	"database/sql"
 	"fmt"
+	"io"
 	"net/url"
 	"strings"
 
@@ -21,6 +22,7 @@ func init() {
 type Driver struct {
 	migrationsTableName string
 	databaseURL         *url.URL
+	log                 io.Writer
 }
 
 // NewDriver initializes the driver
@@ -28,6 +30,7 @@ func NewDriver(config dbmate.DriverConfig) dbmate.Driver {
 	return &Driver{
 		migrationsTableName: config.MigrationsTableName,
 		databaseURL:         config.DatabaseURL,
+		log:                 config.Log,
 	}
 }
 
@@ -92,7 +95,7 @@ func (drv *Driver) quoteIdentifier(str string) string {
 // CreateDatabase creates the specified database
 func (drv *Driver) CreateDatabase() error {
 	name := dbutil.DatabaseName(drv.databaseURL)
-	fmt.Printf("Creating: %s\n", name)
+	fmt.Fprintf(drv.log, "Creating: %s\n", name)
 
 	db, err := drv.openRootDB()
 	if err != nil {
@@ -109,7 +112,7 @@ func (drv *Driver) CreateDatabase() error {
 // DropDatabase drops the specified database (if it exists)
 func (drv *Driver) DropDatabase() error {
 	name := dbutil.DatabaseName(drv.databaseURL)
-	fmt.Printf("Dropping: %s\n", name)
+	fmt.Fprintf(drv.log, "Dropping: %s\n", name)
 
 	db, err := drv.openRootDB()
 	if err != nil {

pkg/driver/postgres/postgres.go

@@ -4,6 +4,7 @@ import (
 	"bytes"
 	"database/sql"
 	"fmt"
+	"io"
 	"net/url"
 	"strings"
 
@@ -22,6 +23,7 @@ func init() {
 type Driver struct {
 	migrationsTableName string
 	databaseURL         *url.URL
+	log                 io.Writer
 }
 
 // NewDriver initializes the driver
@@ -29,6 +31,7 @@ func NewDriver(config dbmate.DriverConfig) dbmate.Driver {
 	return &Driver{
 		migrationsTableName: config.MigrationsTableName,
 		databaseURL:         config.DatabaseURL,
+		log:                 config.Log,
 	}
 }
 
@@ -112,7 +115,7 @@ func (drv *Driver) openPostgresDB() (*sql.DB, error) {
 // CreateDatabase creates the specified database
 func (drv *Driver) CreateDatabase() error {
 	name := dbutil.DatabaseName(drv.databaseURL)
-	fmt.Printf("Creating: %s\n", name)
+	fmt.Fprintf(drv.log, "Creating: %s\n", name)
 
 	db, err := drv.openPostgresDB()
 	if err != nil {
@@ -129,7 +132,7 @@ func (drv *Driver) CreateDatabase() error {
 // DropDatabase drops the specified database (if it exists)
 func (drv *Driver) DropDatabase() error {
 	name := dbutil.DatabaseName(drv.databaseURL)
-	fmt.Printf("Dropping: %s\n", name)
+	fmt.Fprintf(drv.log, "Dropping: %s\n", name)
 
 	db, err := drv.openPostgresDB()
 	if err != nil {
@@ -233,7 +236,7 @@ func (drv *Driver) CreateMigrationsTable(db *sql.DB) error {
 
 	// in theory we could attempt to create the schema every time, but we avoid that
 	// in case the user doesn't have permissions to create schemas
-	fmt.Printf("Creating schema: %s\n", schema)
+	fmt.Fprintf(drv.log, "Creating schema: %s\n", schema)
 	_, err = db.Exec(fmt.Sprintf("create schema if not exists %s", schema))
 	if err != nil {
 		return err

pkg/driver/sqlite/sqlite.go

@@ -6,6 +6,7 @@ import (
 	"bytes"
 	"database/sql"
 	"fmt"
+	"io"
 	"net/url"
 	"os"
 	"regexp"
@@ -27,6 +28,7 @@ func init() {
 type Driver struct {
 	migrationsTableName string
 	databaseURL         *url.URL
+	log                 io.Writer
 }
 
 // NewDriver initializes the driver
@@ -34,6 +36,7 @@ func NewDriver(config dbmate.DriverConfig) dbmate.Driver {
 	return &Driver{
 		migrationsTableName: config.MigrationsTableName,
 		databaseURL:         config.DatabaseURL,
+		log:                 config.Log,
 	}
 }
 
@@ -56,7 +59,7 @@ func (drv *Driver) Open() (*sql.DB, error) {
 
 // CreateDatabase creates the specified database
 func (drv *Driver) CreateDatabase() error {
-	fmt.Printf("Creating: %s\n", ConnectionString(drv.databaseURL))
+	fmt.Fprintf(drv.log, "Creating: %s\n", ConnectionString(drv.databaseURL))
 
 	db, err := drv.Open()
 	if err != nil {
@@ -70,7 +73,7 @@ func (drv *Driver) CreateDatabase() error {
 // DropDatabase drops the specified database (if it exists)
 func (drv *Driver) DropDatabase() error {
 	path := ConnectionString(drv.databaseURL)
-	fmt.Printf("Dropping: %s\n", path)
+	fmt.Fprintf(drv.log, "Dropping: %s\n", path)
 
 	exists, err := drv.DatabaseExists()
 	if err != nil {