Format, example tests, typos, and lint fixes

README.md

@@ -61,7 +61,8 @@ import (
 
 	"github.com/acronis/go-dbkit"
 
-	// Import the `mysql` package for registering the retryable function for MySQL transient errors (like deadlocks).
+	// Import the `mysql` package for registering the retryable function for MySQL transient
+	// errors (like deadlocks).
 	_ "github.com/acronis/go-dbkit/mysql"
 )
 
@@ -89,11 +90,13 @@ func main() {
 	}
 	defer db.Close()
 
-	// Execute a transaction with a custom retry policy (exponential backoff with 3 retries, starting from 10ms).
+	// Execute a transaction with a custom retry policy (exponential backoff with 3 retries,
+	// starting from 10ms).
 	retryPolicy := retry.NewConstantBackoffPolicy(10*time.Millisecond, 3)
 	if err = dbkit.DoInTx(context.Background(), db, func(tx *sql.Tx) error {
 		// Execute your transactional operations here.
-		// Example: _, err := tx.Exec("UPDATE users SET last_login = ? WHERE id = ?", time.Now(), 1)
+		// Example: _, err := tx.Exec("UPDATE users SET last_login = ? WHERE id = ?",
+		// time.Now(), 1)
 		return nil
 	}, dbkit.WithRetryPolicy(retryPolicy)); err != nil {
 		log.Fatal(err)
@@ -112,22 +115,23 @@ package main
 import (
 	"context"
 	"database/sql"
-	"errors"
 	"fmt"
 	stdlog "log"
-	"net/http"
 	"os"
 	"time"
 
 	"github.com/acronis/go-appkit/log"
 	"github.com/gocraft/dbr/v2"
-	
+
 	"github.com/acronis/go-dbkit"
 	"github.com/acronis/go-dbkit/dbrutil"
 )
 
 func main() {
-	logger, loggerClose := log.NewLogger(&log.Config{Output: log.OutputStderr, Level: log.LevelInfo})
+	logger, loggerClose := log.NewLogger(&log.Config{
+		Output: log.OutputStderr,
+		Level:  log.LevelInfo,
+	})
 	defer loggerClose()
 
 	// Create a Prometheus metrics collector.
@@ -150,18 +154,21 @@ func main() {
 	txRunner := dbrutil.NewTxRunner(conn, &sql.TxOptions{Isolation: sql.LevelReadCommitted}, nil)
 
 	// Execute function in a transaction.
-	// The transaction will be automatically committed if the function returns nil, otherwise it will be rolled back.
+	// The transaction will be automatically committed if the function returns nil, otherwise it
+	// will be rolled back.
 	if dbErr := txRunner.DoInTx(context.Background(), func(tx dbr.SessionRunner) error {
 		var result int
 		return tx.Select("SLEEP(1)").
-			Comment(annotateQuery("long_operation")). // Annotate the query for Prometheus metrics and slow query log.
+			// Annotate the query for Prometheus metrics and slow query log.
+			Comment(annotateQuery("long_operation")).
 			LoadOne(&result)
 	}); dbErr != nil {
 		stdlog.Fatal(dbErr)
 	}
 
 	// The following log message will be printed:
-	// {"level":"warn","time":"2025-02-14T16:29:55.429257+02:00","msg":"slow SQL query","pid":14030,"annotation":"query:long_operation","duration_ms":1007}
+	// {"level":"warn","time":"2025-02-14T16:29:55.429257+02:00","msg":"slow SQL query",
+	// "pid":14030, "annotation":"query:long_operation","duration_ms":1007}
 
 	// Prometheus metrics will be collected:
 	// db_query_duration_seconds_bucket{query="query:long_operation",le="2.5"} 1
@@ -187,8 +194,10 @@ func openDB(eventReceiver dbr.EventReceiver) (*dbr.Connection, error) {
 		},
 	}
 
-	// Open database with instrumentation based on the provided event receiver (see github.com/gocraft/dbr doc for details).
-	// Opening includes configuring the max open/idle connections and their lifetime and pinging the database.
+	// Open database with instrumentation based on the provided event receiver
+	// (see github.com/gocraft/dbr doc for details).
+	// Opening includes configuring the max open/idle connections and their lifetime and
+	// pinging the database.
 	conn, err := dbrutil.Open(cfg, true, eventReceiver)
 	if err != nil {
 		return nil, fmt.Errorf("open database: %w", err)
@@ -238,11 +247,13 @@ func main() {
 	}
 
 	// Do some work exclusively.
-	const lockKey = "test-lock-key-1" // Unique key that will be used to ensure exclusive execution among multiple instances
-	err = distrlock.DoExclusively(ctx, db, dbkit.DialectMySQL, lockKey, func(ctx context.Context) error {
-		time.Sleep(10 * time.Second) // Simulate work.
-		return nil
-	})
+	// Unique key that will be used to ensure exclusive execution among multiple instances
+	const lockKey = "test-lock-key-1"
+	err = distrlock.DoExclusively(ctx, db, dbkit.DialectMySQL, lockKey,
+		func(ctx context.Context) error {
+			time.Sleep(10 * time.Second) // Simulate work.
+			return nil
+		})
 	if err != nil {
 		log.Fatal(err)
 	}
@@ -253,7 +264,7 @@ More examples and detailed usage instructions can be found in the `distrlock` pa
 
 ## License
 
-Copyright © 2024 Acronis International GmbH.
+Copyright © 2024-2025 Acronis International GmbH.
 
 Licensed under [MIT License](./LICENSE).
 

config.go

@@ -96,6 +96,7 @@ func NewConfig(supportedDialects []Dialect, options ...ConfigOption) *Config {
 
 // NewConfigWithKeyPrefix creates a new instance of the Config with a key prefix.
 // This prefix will be used by config.Loader.
+//
 // Deprecated: use NewConfig with WithKeyPrefix instead.
 func NewConfigWithKeyPrefix(keyPrefix string, supportedDialects []Dialect) *Config {
 	if keyPrefix != "" {
@@ -266,14 +267,12 @@ func (c *Config) DriverNameAndDSN() (driverName, dsn string) {
 }
 
 func (c *Config) setDialectSpecificConfig(dp config.DataProvider) error {
-	var err error
-
-	var supportedDialectsStr []string
+	supportedDialectsStr := make([]string, 0, len(c.SupportedDialects()))
 	for _, dialect := range c.SupportedDialects() {
 		supportedDialectsStr = append(supportedDialectsStr, string(dialect))
 	}
-	var dialectStr string
-	if dialectStr, err = dp.GetStringFromSet(cfgKeyDialect, supportedDialectsStr, false); err != nil {
+	dialectStr, err := dp.GetStringFromSet(cfgKeyDialect, supportedDialectsStr, false)
+	if err != nil {
 		return err
 	}
 	c.Dialect = Dialect(dialectStr)

dbrutil/README.md

@@ -21,22 +21,23 @@ package main
 import (
 	"context"
 	"database/sql"
-	"errors"
 	"fmt"
 	stdlog "log"
-	"net/http"
 	"os"
 	"time"
 
 	"github.com/acronis/go-appkit/log"
 	"github.com/gocraft/dbr/v2"
-	
+
 	"github.com/acronis/go-dbkit"
 	"github.com/acronis/go-dbkit/dbrutil"
 )
 
 func main() {
-	logger, loggerClose := log.NewLogger(&log.Config{Output: log.OutputStderr, Level: log.LevelInfo})
+	logger, loggerClose := log.NewLogger(&log.Config{
+		Output: log.OutputStderr,
+		Level:  log.LevelInfo,
+	})
 	defer loggerClose()
 
 	// Create a Prometheus metrics collector.
@@ -59,18 +60,21 @@ func main() {
 	txRunner := dbrutil.NewTxRunner(conn, &sql.TxOptions{Isolation: sql.LevelReadCommitted}, nil)
 
 	// Execute function in a transaction.
-	// The transaction will be automatically committed if the function returns nil, otherwise it will be rolled back.
+	// The transaction will be automatically committed if the function returns nil, otherwise it
+	// will be rolled back.
 	if dbErr := txRunner.DoInTx(context.Background(), func(tx dbr.SessionRunner) error {
 		var result int
 		return tx.Select("SLEEP(1)").
-			Comment(annotateQuery("long_operation")). // Annotate the query for Prometheus metrics and slow query log.
+			// Annotate the query for Prometheus metrics and slow query log.
+			Comment(annotateQuery("long_operation")).
 			LoadOne(&result)
 	}); dbErr != nil {
 		stdlog.Fatal(dbErr)
 	}
 
 	// The following log message will be printed:
-	// {"level":"warn","time":"2025-02-14T16:29:55.429257+02:00","msg":"slow SQL query","pid":14030,"annotation":"query:long_operation","duration_ms":1007}
+	// {"level":"warn","time":"2025-02-14T16:29:55.429257+02:00","msg":"slow SQL query",
+	// "pid":14030, "annotation":"query:long_operation","duration_ms":1007}
 
 	// Prometheus metrics will be collected:
 	// db_query_duration_seconds_bucket{query="query:long_operation",le="2.5"} 1
@@ -96,8 +100,10 @@ func openDB(eventReceiver dbr.EventReceiver) (*dbr.Connection, error) {
 		},
 	}
 
-	// Open database with instrumentation based on the provided event receiver (see github.com/gocraft/dbr doc for details).
-	// Opening includes configuring the max open/idle connections and their lifetime and pinging the database.
+	// Open database with instrumentation based on the provided event receiver
+	// (see github.com/gocraft/dbr doc for details).
+	// Opening includes configuring the max open/idle connections and their lifetime and
+	// pinging the database.
 	conn, err := dbrutil.Open(cfg, true, eventReceiver)
 	if err != nil {
 		return nil, fmt.Errorf("open database: %w", err)
@@ -184,7 +190,14 @@ func main() {
 	mux := http.NewServeMux()
 	mux.Handle("/long-operation", h)
 	mux.Handle("/metrics", promhttp.Handler())
-	if srvErr := http.ListenAndServe(":8080", mux); srvErr != nil && errors.Is(srvErr, http.ErrServerClosed) {
+	srv := &http.Server{
+		Addr:         ":8080",
+		Handler:      mux,
+		ReadTimeout:  5 * time.Second,
+		WriteTimeout: 10 * time.Second,
+		IdleTimeout:  120 * time.Second,
+	}
+	if srvErr := srv.ListenAndServe(); srvErr != nil && !errors.Is(srvErr, http.ErrServerClosed) {
 		stdlog.Fatalf("failed to start server: %v", srvErr)
 	}
 }
@@ -241,7 +254,7 @@ db_query_duration_seconds_count{query="query:long_operation"} 1
 
 ## License
 
-Copyright © 2024 Acronis International GmbH.
+Copyright © 2025-2026 Acronis International GmbH.
 
 Licensed under [MIT License](./../LICENSE).
 

dbrutil/dbrutil.go

@@ -69,7 +69,7 @@ func (e *TxRollbackError) Error() string {
 	return fmt.Sprintf("error while transaction rollback: %s", e.Inner)
 }
 
-// TxBeginError is a error that may occur when begging transaction is failed.
+// TxBeginError is an error that may occur when beginning a transaction fails.
 type TxBeginError struct {
 	Inner error
 }
@@ -81,7 +81,7 @@ func (e *TxBeginError) Unwrap() error {
 
 // Error returns a string representation of TxBeginError.
 func (e *TxBeginError) Error() string {
-	return fmt.Sprintf("error while begging transaction: %s", e.Inner)
+	return fmt.Sprintf("error while beginning transaction: %s", e.Inner)
 }
 
 // TxRunner can begin a new transaction and provides the ability to execute code inside already started one.
@@ -121,6 +121,8 @@ func (s *TxSession) BeginTx(ctx context.Context) (*dbr.Tx, error) {
 
 // DoInTx begins a new transaction, calls passed function and do commit or rollback
 // depending on whether the function returns an error or not.
+//
+//nolint:contextcheck // inherited context is replaced for sqlite3, see comment below
 func (s *TxSession) DoInTx(ctx context.Context, fn func(runner dbr.SessionRunner) error) error {
 	if s.Dialect == dialect.SQLite3 {
 		// race of ctx cancel with transaction begin leads to 'cannot start a transaction within a transaction'

dbrutil/examples/dbr-instrumentation-1/main.go

@@ -1,5 +1,5 @@
 /*
-Copyright © 2025 Acronis International GmbH.
+Copyright © 2025-2026 Acronis International GmbH.
 
 Released under MIT license.
 */
@@ -22,7 +22,10 @@ import (
 )
 
 func main() {
-	logger, loggerClose := log.NewLogger(&log.Config{Output: log.OutputStderr, Level: log.LevelInfo})
+	logger, loggerClose := log.NewLogger(&log.Config{
+		Output: log.OutputStderr,
+		Level:  log.LevelInfo,
+	})
 	defer loggerClose()
 
 	// Create a Prometheus metrics collector.
@@ -45,11 +48,13 @@ func main() {
 	txRunner := dbrutil.NewTxRunner(conn, &sql.TxOptions{Isolation: sql.LevelReadCommitted}, nil)
 
 	// Execute function in a transaction.
-	// The transaction will be automatically committed if the function returns nil, otherwise it will be rolled back.
+	// The transaction will be automatically committed if the function returns nil, otherwise it
+	// will be rolled back.
 	if dbErr := txRunner.DoInTx(context.Background(), func(tx dbr.SessionRunner) error {
 		var result int
 		return tx.Select("SLEEP(1)").
-			Comment(annotateQuery("long_operation")). // Annotate the query for Prometheus metrics and slow query log.
+			// Annotate the query for Prometheus metrics and slow query log.
+			Comment(annotateQuery("long_operation")).
 			LoadOne(&result)
 	}); dbErr != nil {
 		stdlog.Fatal(dbErr)
@@ -83,8 +88,10 @@ func openDB(eventReceiver dbr.EventReceiver) (*dbr.Connection, error) {
 		},
 	}
 
-	// Open database with instrumentation based on the provided event receiver (see github.com/gocraft/dbr doc for details).
-	// Opening includes configuring the max open/idle connections and their lifetime and pinging the database.
+	// Open database with instrumentation based on the provided event receiver
+	// (see github.com/gocraft/dbr doc for details).
+	// Opening includes configuring the max open/idle connections and their lifetime and
+	// pinging the database.
 	conn, err := dbrutil.Open(cfg, true, eventReceiver)
 	if err != nil {
 		return nil, fmt.Errorf("open database: %w", err)

dbrutil/examples/dbr-instrumentation-2/main.go

@@ -84,7 +84,7 @@ func main() {
 		WriteTimeout: 10 * time.Second,
 		IdleTimeout:  120 * time.Second,
 	}
-	if srvErr := srv.ListenAndServe(); srvErr != nil && errors.Is(srvErr, http.ErrServerClosed) {
+	if srvErr := srv.ListenAndServe(); srvErr != nil && !errors.Is(srvErr, http.ErrServerClosed) {
 		stdlog.Fatalf("failed to start server: %v", srvErr)
 	}
 }

distrlock/README.md

@@ -57,11 +57,13 @@ func main() {
 	}
 
 	// Do some work exclusively.
-	const lockKey = "test-lock-key-1" // Unique key that will be used to ensure exclusive execution among multiple instances
-	err = distrlock.DoExclusively(ctx, db, dbkit.DialectMySQL, lockKey, func(ctx context.Context) error {
-		time.Sleep(10 * time.Second) // Simulate work.
-		return nil
-	})
+	// Unique key that will be used to ensure exclusive execution among multiple instances
+	const lockKey = "test-lock-key-1"
+	err = distrlock.DoExclusively(ctx, db, dbkit.DialectMySQL, lockKey,
+		func(ctx context.Context) error {
+			time.Sleep(10 * time.Second) // Simulate work.
+			return nil
+		})
 	if err != nil {
 		log.Fatal(err)
 	}
@@ -107,7 +109,8 @@ func main() {
 		log.Fatal(err)
 	}
 
-	const lockKey = "test-lock-key-2" // Unique key that will be used to ensure exclusive execution among multiple instances
+	// Unique key that will be used to ensure exclusive execution among multiple instances
+	const lockKey = "test-lock-key-2"
 
 	// Create lock.
 	lock, err := lockManager.NewLock(ctx, db, lockKey)
@@ -126,13 +129,13 @@ func main() {
 		}
 	}()
 
-	time.Sleep(10 * time.Second) // Simulate work
+	time.Sleep(11 * time.Second) // Simulate work
 }
 ```
 
 ## License
 
-Copyright © 2024 Acronis International GmbH.
+Copyright © 2024-2025 Acronis International GmbH.
 
 Licensed under [MIT License](./../LICENSE).