Add slog support to goose provider

provider.go

@@ -5,8 +5,11 @@ import (
 	"database/sql"
 	"errors"
 	"fmt"
+	"io"
 	"io/fs"
+	"log/slog"
 	"math"
+	"os"
 	"strconv"
 	"strings"
 	"sync"
@@ -62,13 +65,32 @@ func NewProvider(dialect Dialect, db *sql.DB, fsys fs.FS, opts ...ProviderOption
 		registered:      make(map[int64]*Migration),
 		excludePaths:    make(map[string]bool),
 		excludeVersions: make(map[int64]bool),
-		logger:          &stdLogger{},
 	}
 	for _, opt := range opts {
 		if err := opt.apply(&cfg); err != nil {
 			return nil, err
 		}
 	}
+	if cfg.logger == nil {
+		output := io.Discard
+		if cfg.verbose {
+			output = os.Stdout
+		}
+		replaceAttr := func(groups []string, a slog.Attr) slog.Attr {
+			if a.Key == slog.TimeKey {
+				return slog.Attr{
+					Key:   slog.TimeKey,
+					Value: slog.StringValue(a.Value.Time().Format("2006-01-02 15:04:05")),
+				}
+			}
+			return a
+		}
+		handler := slog.NewTextHandler(output, &slog.HandlerOptions{
+			Level:       slog.LevelInfo,
+			ReplaceAttr: replaceAttr,
+		})
+		cfg.logger = slog.New(handler).With(slog.String("logger", "goose"))
+	}
 	// Allow users to specify a custom store implementation, but only if they don't specify a
 	// dialect. If they specify a dialect, we'll use the default store implementation.
 	if dialect == "" && cfg.store == nil {
@@ -118,8 +140,9 @@ func newProvider(
 	}
 	// Skip adding global Go migrations if explicitly disabled.
 	if cfg.disableGlobalRegistry {
-		// TODO(mf): let's add a warn-level log here to inform users if len(global) > 0. Would like
-		// to add this once we're on go1.21 and leverage the new slog package.
+		if len(global) > 0 {
+			cfg.logger.Warn("detected global go migrations, but global go migrations are disabled", slog.Int("count", len(global)))
+		}
 	} else {
 		for version, m := range global {
 			if _, ok := versionToGoMigration[version]; ok {
@@ -434,7 +457,7 @@ func (p *Provider) down(
 	}
 	// We never migrate the zero version down.
 	if dbMigrations[0].Version == 0 {
-		p.printf("no migrations to run, current version: 0")
+		p.cfg.logger.Info("no migrations to run, current version: 0")
 		return nil, nil
 	}
 	var apply []*Migration

provider_options.go

@@ -3,6 +3,7 @@ package goose
 import (
 	"errors"
 	"fmt"
+	"log/slog"
 
 	"github.com/pressly/goose/v3/database"
 	"github.com/pressly/goose/v3/lock"
@@ -165,10 +166,20 @@ func WithDisableVersioning(b bool) ProviderOption {
 	})
 }
 
+// WithLogger sets the logger to use for logging. By default, goose will use a modified version of
+// the [slog.NewTextHandler] with a custom format.
+func WithLogger(logger *slog.Logger) ProviderOption {
+	return configFunc(func(c *config) error {
+		c.logger = logger
+		return nil
+	})
+}
+
 type config struct {
 	store database.Store
 
 	verbose         bool
+	logger          *slog.Logger
 	excludePaths    map[string]bool
 	excludeVersions map[int64]bool
 
@@ -184,11 +195,6 @@ type config struct {
 	disableVersioning     bool
 	allowMissing          bool
 	disableGlobalRegistry bool
-
-	// Let's not expose the Logger just yet. Ideally we consolidate on the std lib slog package
-	// added in go1.21 and then expose that (if that's even necessary). For now, just use the std
-	// lib log package.
-	logger Logger
 }
 
 type configFunc func(*config) error

provider_run.go

@@ -6,8 +6,9 @@ import (
 	"errors"
 	"fmt"
 	"io/fs"
+	"log/slog"
+	"path/filepath"
 	"runtime/debug"
-	"strings"
 	"time"
 
 	"github.com/pressly/goose/v3/database"
@@ -66,17 +67,6 @@ func (p *Provider) prepareMigration(fsys fs.FS, m *Migration, direction bool) er
 	return fmt.Errorf("invalid migration type: %+v", m)
 }
 
-// printf is a helper function that prints the given message if verbose is enabled. It also prepends
-// the "goose: " prefix to the message.
-func (p *Provider) printf(msg string, args ...interface{}) {
-	if p.cfg.verbose {
-		if !strings.HasPrefix(msg, "goose:") {
-			msg = "goose: " + msg
-		}
-		p.cfg.logger.Printf(msg, args...)
-	}
-}
-
 // runMigrations runs migrations sequentially in the given direction. If the migrations list is
 // empty, return nil without error.
 func (p *Provider) runMigrations(
@@ -94,7 +84,7 @@ func (p *Provider) runMigrations(
 			if err != nil {
 				return nil, err
 			}
-			p.printf("no migrations to run, current version: %d", maxVersion)
+			p.cfg.logger.Info("no migrations to run", slog.Int64("current_version", maxVersion))
 		}
 		return nil, nil
 	}
@@ -150,14 +140,19 @@ func (p *Provider) runMigrations(
 		}
 		result.Duration = time.Since(start)
 		results = append(results, result)
-		p.printf("%s", result)
+		p.cfg.logger.Info("applied migration",
+			slog.String("source", filepath.Base(m.Source)),
+			slog.Any("direction", direction),
+			slog.Any("duration", result.Duration),
+			slog.Bool("empty", result.Empty),
+		)
 	}
 	if !p.cfg.disableVersioning && !byOne {
 		maxVersion, err := p.getDBMaxVersion(ctx, conn)
 		if err != nil {
 			return nil, err
 		}
-		p.printf("successfully migrated database, current version: %d", maxVersion)
+		p.cfg.logger.Info("successfully migrated database", slog.Int64("current_version", maxVersion))
 	}
 	return results, nil
 }