增加服务流量统计

internal/caches/errors.go

@@ -0,0 +1,41 @@
+// Copyright 2021 Liuxiangchao iwind.liu@gmail.com. All rights reserved.
+
+package caches
+
+import "errors"
+
+// 常用的几个错误
+var (
+	ErrNotFound      = errors.New("cache not found")
+	ErrFileIsWriting = errors.New("the file is writing")
+	ErrInvalidRange  = errors.New("invalid range")
+)
+
+// CapacityError 容量错误
+// 独立出来是为了可以在有些场合下可以忽略，防止产生没必要的错误提示数量太多
+type CapacityError struct {
+	err string
+}
+
+func NewCapacityError(err string) error {
+	return &CapacityError{err: err}
+}
+
+func (this *CapacityError) Error() string {
+	return this.err
+}
+
+// CanIgnoreErr 检查错误是否可以忽略
+func CanIgnoreErr(err error) bool {
+	if err == nil {
+		return true
+	}
+	if err == ErrFileIsWriting {
+		return true
+	}
+	_, ok := err.(*CapacityError)
+	if ok {
+		return true
+	}
+	return false
+}