feat: bunslog.QueryHook for Bun logging using log/slog

[hirasawayuki]

Description

This PR implements a new package called bunslog to support enhanced logging functionalities for the Bun using log/slog.

ref #903

Features

• Supports setting a *slog.Logger instance or uses the global logger if not set.
• Logs general SQL queries with configurable log levels.
• Logs slow SQL queries based on a configurable duration threshold.
• Logs SQL queries that result in errors, for easier debugging.
• Allows for custom log formatting.

Usage

Simply create a new QueryHook and add it to existing *db.Bun database instance.

logger := slog.New(slog.NewJSONHandler(os.Stdout, &slog.HandlerOptions{Level: slog.LevelDebug}))
slog.SetDefault(logger)

db := bun.NewDB(sqldb, dialect)
hook := bunslog.NewQueryHook(
    bunslog.WithQueryLogLevel(slog.LevelDebug),
    bunslog.WithSlowQueryLogLevel(slog.LevelWarn),
    bunslog.WithErrorQueryLogLevel(slog.LevelError),
    bunslog.WithSlowQueryThreshold(3 * time.Second),
)
db.AddQueryHook(hook)

[vmihailenco]

@hirasawayuki Looks good, thanks. Could you add a go.mod file so we don't require log/slog which is only available starting from the Go 1.21.

[hirasawayuki]

@vmihailenco
I've made some modifications to the implementation:

• Updated to allow for passing an instance of slog.Logger as an option, in addition to using the default logger.
• Added the ability to set a custom format through an option.
  I would appreciate another review! Thank you!

(It appears that the build is failing for Go 1.19 and Go 1.20 due to the import of log/slog. Would it be a good idea to also modify the Makefile to avoid loading it during the build?)

[vmihailenco]

Would it be a good idea to also modify the Makefile to avoid loading it during the build?)

Let's just bump Go in tests to v1.21.

[vmihailenco]

Thanks!