Added log level support to SimpleLogger (#426)

Implement Log levels.
Can be used as the default logger.
Default log level can be later specified via configuration, or
environment variable.
I had been using the library and found out that I needed to define a
custom logger to suppress logs, to be specific
I was using the `dbfsAPI` to upload files, and I was getting bombarded
with logs with each `add_block` request.

## Changes
<!-- Summary of your changes that are easy to understand -->
Add new Implementation for the `Logger` interface which respects the log
level.
## Tests

added 2 new tests found in [level
-logger_test.go](logger/level_logger_test.go)


- [x] `make test` passing
- [x] `make fmt` applied
- [ ] relevant integration tests applied

logger/logger_test.go

@@ -23,3 +23,29 @@ func TestGetLogger(t *testing.T) {
 	logger = Get(ctx)
 	assert.Equal(t, logger, t2)
 }
+
+func TestWhenInfoLevelThenDebugDisabled(t *testing.T) {
+	t.Cleanup(func() {
+		DefaultLogger = &SimpleLogger{}
+	})
+
+	infoLevelLogger := &SimpleLogger{
+		Level: LevelInfo,
+	}
+	debugEnabled := infoLevelLogger.Enabled(context.Background(), LevelDebug)
+	assert.False(t, debugEnabled)
+}
+
+func TestWhenInfoLevelThenErrorEnabled(t *testing.T) {
+	infoLevelLogger := &SimpleLogger{
+		Level: LevelInfo,
+	}
+
+	errorEnabled := infoLevelLogger.Enabled(context.Background(), LevelError)
+	assert.True(t, errorEnabled)
+}
+
+func TestDefaultLevelInfo(t *testing.T) {
+	logger := &SimpleLogger{}
+	assert.EqualValues(t, LevelInfo, logger.Level)
+}

logger/simple.go

@@ -5,28 +5,45 @@ import (
 	"log"
 )
 
-type SimpleLogger struct{}
+type SimpleLogger struct {
+	Level Level
+}
 
 func (l *SimpleLogger) Enabled(_ context.Context, level Level) bool {
-	return true
+	return level >= l.Level
 }
 
-func (l *SimpleLogger) Tracef(_ context.Context, format string, v ...any) {
+func (l *SimpleLogger) Tracef(ctx context.Context, format string, v ...any) {
+	if !l.Enabled(ctx, LevelTrace) {
+		return
+	}
 	log.Printf("[TRACE] "+format, v...)
 }
 
-func (l *SimpleLogger) Debugf(_ context.Context, format string, v ...any) {
+func (l *SimpleLogger) Debugf(ctx context.Context, format string, v ...any) {
+	if !l.Enabled(ctx, LevelDebug) {
+		return
+	}
 	log.Printf("[DEBUG] "+format, v...)
 }
 
-func (l *SimpleLogger) Infof(_ context.Context, format string, v ...any) {
+func (l *SimpleLogger) Infof(ctx context.Context, format string, v ...any) {
+	if !l.Enabled(ctx, LevelInfo) {
+		return
+	}
 	log.Printf("[INFO] "+format, v...)
 }
 
-func (l *SimpleLogger) Warnf(_ context.Context, format string, v ...any) {
+func (l *SimpleLogger) Warnf(ctx context.Context, format string, v ...any) {
+	if !l.Enabled(ctx, LevelWarn) {
+		return
+	}
 	log.Printf("[WARN] "+format, v...)
 }
 
-func (l *SimpleLogger) Errorf(_ context.Context, format string, v ...any) {
+func (l *SimpleLogger) Errorf(ctx context.Context, format string, v ...any) {
+	if !l.Enabled(ctx, LevelError) {
+		return
+	}
 	log.Printf("[ERROR] "+format, v...)
 }