restore v 0.2.0

middleware.go

@@ -0,0 +1,111 @@
+package log
+
+import (
+	"context"
+	"fmt"
+	"path/filepath"
+	"runtime"
+	"time"
+)
+
+// Middleware handle.
+type Middleware func(ctx context.Context, level Level, msg string, fields Fields, handler Logger)
+
+// With add middleware to logger.
+func With(logger Logger, mw ...Middleware) Logger {
+	switch len(mw) {
+	case 0:
+		return logger
+	case 1:
+		return func(ctx context.Context, level Level, msg string, fields Fields) {
+			mw[0](ctx, level, msg, fields, logger)
+		}
+	}
+
+	lastI := len(mw) - 1
+
+	return func(ctx context.Context, level Level, msg string, fields Fields) {
+		var (
+			chainHandler func(ctx context.Context, level Level, msg string, fields Fields)
+			curI         int
+		)
+
+		chainHandler = func(currentCtx context.Context, currentLevel Level, currentMsg string, currentFields Fields) {
+			if curI == lastI {
+				logger(currentCtx, currentLevel, currentMsg, currentFields)
+				return
+			}
+			curI++
+			mw[curI](currentCtx, currentLevel, currentMsg, currentFields, chainHandler)
+			curI--
+		}
+
+		mw[0](ctx, level, msg, fields, chainHandler)
+	}
+}
+
+// WithLevel sets log level.
+func WithLevel(lvl Level) Middleware {
+	return func(ctx context.Context, level Level, msg string, fields Fields, handler Logger) {
+		if level <= lvl {
+			handler(ctx, level, msg, append(fields, Field{Key: "level", Value: level}))
+		}
+	}
+}
+
+// KeyValue add field by const key value.
+func KeyValue(key string, value interface{}) Middleware {
+	return func(ctx context.Context, level Level, msg string, fields Fields, handler Logger) {
+		handler(ctx, level, msg, append(fields, Field{Key: key, Value: value}))
+	}
+}
+
+// GoVersion add field by go version.
+func GoVersion(key string) Middleware {
+	return func(ctx context.Context, level Level, msg string, fields Fields, handler Logger) {
+		handler(ctx, level, msg, append(fields, Field{Key: key, Value: runtime.Version()}))
+	}
+}
+
+// WithContext add field by context key.
+func WithContextValue(keys ...fmt.Stringer) Middleware {
+	return func(ctx context.Context, level Level, msg string, fields Fields, handler Logger) {
+		ctxFields := make(Fields, len(keys))
+		for i, key := range keys {
+			ctxFields[i] = Field{Key: key.String(), Value: ctx.Value(key)}
+		}
+
+		handler(ctx, level, msg, append(fields, ctxFields...))
+	}
+}
+
+// WithCaller adds called file.
+func WithCaller(calldepth int, short bool) Middleware {
+	return func(ctx context.Context, level Level, msg string, fields Fields, handler Logger) {
+		_, file, line, ok := runtime.Caller(calldepth)
+		if !ok {
+			file, line = "???", 0
+		}
+
+		if short && ok {
+			file = filepath.Base(file)
+		}
+
+		handler(ctx, level, msg, append(fields, NewField("caller", fmt.Sprint(file, ":", line))))
+	}
+}
+
+// WithTime adds time.
+func WithTime(format string) Middleware {
+	return func(ctx context.Context, level Level, msg string, fields Fields, handler Logger) {
+		handler(ctx, level, msg, append(fields, NewField("time", time.Now().Format(format))))
+	}
+}
+
+// WithMetrics adds handle metrics.
+func WithMetrics(metrics func(level Level)) Middleware {
+	return func(ctx context.Context, level Level, msg string, fields Fields, handler Logger) {
+		go metrics(level)
+		handler(ctx, level, msg, fields)
+	}
+}