slogGorm

README

slog-gorm

slog-gorm provides a slog adapter, highly configurable, for gorm logger to have homogeneous logs between your application / script and gorm.

Key features

• compatible with any slog.Handler, which allows you to keep control on the format of your logs.
• can define a threshold to identify and log the slow queries.
• can log all SQL messages or just the errors if you prefer.
• can define a custom slog.Level for errors, slow queries or the other logs.
• can log context values with each Gorm log.

Requirement

• golang >= 1.21

Usage

import (
    "log/slog"
    "os"

    "gorm.io/driver/sqlite"
    "gorm.io/gorm"

    slogGorm "github.com/orandin/slog-gorm"
)

// Create an slog-gorm instance
gormLogger := slogGorm.New() // use slog.Default() by default


// GORM: Globally mode
db, err := gorm.Open(sqlite.Open("test.db"), &gorm.Config{
    Logger: gormLogger,
})

// GORM: Continuous session mode
tx := db.Session(&Session{Logger: gormLogger})
tx.First(&user)
tx.Model(&user).Update("Age", 18)

With your slog.Logger

The following example shows you how to use a specific slog.Logger with slog-gorm:

// With your slog.Logger
logger := slog.New(slog.NewJSONHandler(os.Stdout, nil))

// Also, you can set specific attributes to distinguish between your application logs and gorm logs
// logger = logger.With(slog.String("log_type", "database"))

gormLogger := slogGorm.New(
    // slogGorm.WithLogger(logger), // Deprecated since v1.3.0, use `slogGorm.WithHandler(...)` instead.
    slogGorm.WithHandler(logger.Handler()), // since v1.3.0
    slogGorm.WithTraceAll(), // trace all messages 
    slogGorm.SetLogLevel(DefaultLogType, slog.Level(32)), // Define the default logging level
)

Use your custom slog.Level

As some loggers (e.g. syslog) have their own logging levels, slog-gorm lets you use them to ensure the consistency of your logs and make them easier to understand.

You can set the logging level for these log types:

Type	Description	Default
slogGorm.ErrorLogType	For SQL errors	slog.LevelError
slogGorm.SlowQueryLogType	For slow queries	slog.LevelWarn
slogGorm.DefaultLogType	For other messages (default level)	slog.LevelInfo

Example:

const (
    LOG_EMERG   = slog.Level(0)
    // ...
    LOG_ERR     = slog.Level(3)
    LOG_WARNING = slog.Level(4)
    LOG_NOTICE  = slog.Level(5)
    // ...
    LOG_DEBUG   = slog.Level(7)
)

logger := slog.New(syslogHandler)

gormLogger := slogGorm.New(
    slogGorm.WithHandler(logger.Handler()),

    // Set logging level for SQL errors
    slogGorm.SetLogLevel(slogGorm.ErrorLogType, LOG_ERR)

    // Set logging level for slow queries
    slogGorm.SetLogLevel(slogGorm.SlowQueryLogType, LOG_NOTICE)

    // Set logging level for other messages (default level)
    slogGorm.SetLogLevel(slogGorm.DefaultLogType, LOG_DEBUG)
)

Other options

customLogger := sloggorm.New(
	slogGorm.WithSlowThreshold(500 * time.Millisecond), // to identify slow queries

	slogGorm.WithRecordNotFoundError(), // don't ignore not found errors

	slogGorm.WithSourceField("origin"), // instead of "file" (by default)

	slogGorm.WithErrorField("err"),     // instead of "error" (by default)

	slogGorm.WithContextValue("slogAttrName", "ctxKey"), // adds an slog.Attr if a value if found for this key in the Gorm's query context
)

By default, the slow queries and SQL errors are logged, but you can ignore all SQL messages with WithIgnoreTrace().

customLogger := sloggorm.New(
    slogGorm.WithIgnoreTrace(), // disable the tracing of SQL queries by the logger.
)

Documentation

Index

• Constants
• func New(options ...Option) *logger
• type LogType
• type Option
  • func SetLogLevel(key LogType, level slog.Level) Option
  • func WithContextValue(slogAttrName, contextKey string) Option
  • func WithErrorField(field string) Option
  • func WithHandler(handler slog.Handler) Option
  • func WithIgnoreTrace() Option
  • func WithLogger(log *slog.Logger) Option
  • func WithRecordNotFoundError() Option
  • func WithSlowThreshold(threshold time.Duration) Option
  • func WithSourceField(field string) Option
  • func WithTraceAll() Option

Constants

const (
	ErrorLogType     LogType = "sql_error"
	SlowQueryLogType LogType = "slow_query"
	DefaultLogType   LogType = "default"

	SourceField    = "file"
	ErrorField     = "error"
	QueryField     = "query"
	DurationField  = "duration"
	SlowQueryField = "slow_query"
	RowsField      = "rows"
)

Functions

func New

func New(options ...Option) *logger

New creates a new logger for gorm.io/gorm

Types

type LogType

type LogType string

type Option

type Option func(l *logger)

func SetLogLevel

func SetLogLevel(key LogType, level slog.Level) Option

SetLogLevel sets a new slog.Level for a LogType.

func WithContextValue

func WithContextValue(slogAttrName, contextKey string) Option

WithContextValue adds a context value to the log

func WithErrorField

func WithErrorField(field string) Option

WithErrorField defines the field to set the error

func WithHandler

func WithHandler(handler slog.Handler) Option

WithHandler defines a custom logger to use

func WithIgnoreTrace

func WithIgnoreTrace() Option

WithIgnoreTrace disables the tracing of SQL queries by the slogger

func WithLogger

func WithLogger(log *slog.Logger) Option

WithLogger defines a custom logger to use

Deprecated: Use WithHandler instead

func WithRecordNotFoundError

func WithRecordNotFoundError() Option

WithRecordNotFoundError allows the slogger to log gorm.ErrRecordNotFound errors

func WithSlowThreshold

func WithSlowThreshold(threshold time.Duration) Option

WithSlowThreshold defines the threshold above which a sql query is considered slow

func WithSourceField

func WithSourceField(field string) Option

WithSourceField defines the field to set the file name and line number of the current file

func WithTraceAll

func WithTraceAll() Option

WithTraceAll enables mode which logs all SQL messages.