defaults

README

Defaults

Provide some global default values.

Documentation

Overview

Package defaults provides some global default values.

Package defaults provides some global default values.

Index

• Variables
• func GetRemoteAddr(ctx context.Context, req interface{}) (netip.Addr, error)
• func GetRequestID(ctx context.Context, req interface{}) string
• func GetStructFieldName(sf reflect.StructField) (name, arg string)
• func Now() time.Time
• func ValidateStruct(value interface{}) (err error)
• func ValidateWithRule(value interface{}, rule string) (err error)
• type Value
  • func NewValue[T any](initial T) *Value[T]
  • func NewValueWithValidation[T any](initial T, validate func(T) error) *Value[T]
  • func (v *Value[T]) Get() T
  • func (v *Value[T]) Set(new T)
  • func (v *Value[T]) Validate(value T) error

Variables

var (
	// GetRequestIDFunc is used to get the unique request session id.
	//
	// For the default implementation, it only detects req
	// and supports the types or interfaces:
	//
	//	*http.Request
	//	interface{ RequestID() string }
	//	interface{ GetRequestID() string }
	//	interface{ GetRequest() *http.Request }
	//	interface{ GetHTTPRequest() *http.Request }
	//
	// For *http.Request, it will returns the header "X-Request-Id".
	//
	// Return "" instead if not found.
	GetRequestIDFunc = NewValueWithValidation(getRequestID, reqidValidateFunc)

	// GetRemoteAddrFunc is used to get the remote address.
	//
	// For the default implementation, it only detects req
	// and supports the types or interfaces:
	//
	//	*http.Request
	//	interface{ GetRequest() *http.Request }
	//	interface{ GetHTTPRequest() *http.Request }
	//	interface{ RemoteAddr() string }
	//	interface{ RemoteAddr() net.IP }
	//	interface{ RemoteAddr() net.Addr }
	//	interface{ RemoteAddr() netip.Addr }
	GetRemoteAddrFunc = NewValueWithValidation(getRemoteAddr, raddrValidateFunc)
)

var (
	TimeFormat   = NewValueWithValidation(time.RFC3339Nano, validateTimeFormat)
	TimeFormats  = NewValueWithValidation([]string{time.RFC3339Nano, "2006-01-02 15:04:05"}, validateTimeFormats)
	TimeLocation = NewValueWithValidation(time.UTC, validateTimeLocation)
	TimeNowFunc  = NewValueWithValidation(time.Now, validateTimeNow)
)

Pre-define some global variables about time.

var (
	// RuleValidator is used to validate whether a value conforms with the rule.
	//
	// Note: in general, it is used to validate a struct field with the tag rule.
	RuleValidator = NewValue(assists.RuleValidator(nil))

	// StructValidator is used to validate whether a struct value is valid.
	StructValidator = NewValue(assists.StructValidator(nil))
)

var (
	// StructFieldNameFunc is used to get the obtain the name and arg
	// of the struct field, which needs to return a empty string for
	// the field name, that's "", if the field should be ignored.
	//
	// Example:
	//
	//	StructFieldNameFunc.Set(func(sf reflect.StructField) (name string, arg string) {
	//	    value := sf.Tag.Get("json")
	//	    if index := strings.IndexByte(value, ','); index > -1 {
	//	        arg = strings.TrimSpace(value[index+1:])
	//	        value = strings.TrimSpace(value[:index])
	//	    }
	//
	//	    switch value {
	//	    case "-":
	//	    case "":
	//	        name = sf.Name
	//	    default:
	//	        name = value
	//	    }
	//
	//	    return
	//	})
	//
	StructFieldNameFunc = NewValueWithValidation(assists.StructFieldNameFuncWithTags("json"), validateStructFieldName)
)

Functions

func GetRemoteAddr

func GetRemoteAddr(ctx context.Context, req interface{}) (netip.Addr, error)

GetRemoteAddr is the proxy of GetRemoteAddrFunc to call the function.

func GetRequestID

func GetRequestID(ctx context.Context, req interface{}) string

GetRequestID is the proxy of GetRequestIDFunc to call the function.

func GetStructFieldName

func GetStructFieldName(sf reflect.StructField) (name, arg string)

GetStructFieldName is the proxy of StructFieldNameFunc to call the function, just like StructFieldNameFunc.Get()(sf).

func Now

func Now() time.Time

Now returns the current time by using TimeNow and TimeLocation.

func ValidateStruct

func ValidateStruct(value interface{}) (err error)

ValidateStruct uses Validator to validate the struct value if StructValidator is not nil.

func ValidateWithRule

func ValidateWithRule(value interface{}, rule string) (err error)

ValidateWithRule uses RuleValidator to validate a value conforms with the rule if RuleValidator is not nil.

Types

type Value

type Value[T any] struct {
	// contains filtered or unexported fields
}

Value represents a common value.

func NewValue

func NewValue[T any](initial T) *Value[T]

NewValue returns a new Value with the initial value.

func NewValueWithValidation

func NewValueWithValidation[T any](initial T, validate func(T) error) *Value[T]

NewValueWithValidation returns a new Value with the initial value and the validation.

validate may be nil, which is equal to always return nil.

func (*Value[T]) Get

func (v *Value[T]) Get() T

Get returns the inner value.

func (*Value[T]) Set

func (v *Value[T]) Set(new T)

Set sets the value to new thread-safely.

It will panic if failing to validate the new value.

func (*Value[T]) Validate

func (v *Value[T]) Validate(value T) error

Validate validate whether the input value is valid.