binding

Documentation

Index

• Constants
• Variables
• func Bind(req *http.Request, obj interface{}) error
• func MapFormWithTag(ptr interface{}, form map[string][]string, tag string) error
• type Binding
  • func Default(method, contentType string) Binding
• type BindingBody
• type BindingUri
• type SliceValidationError
  • func (err SliceValidationError) Error() string
• type StructValidator

Constants

const (
	MIMEJSON              = "application/json"
	MIMEHTML              = "text/html"
	MIMEXML               = "application/xml"
	MIMEXML2              = "text/xml"
	MIMEPlain             = "text/plain"
	MIMEPOSTForm          = "application/x-www-form-urlencoded"
	MIMEMultipartPOSTForm = "multipart/form-data"
	MIMEPROTOBUF          = "application/x-protobuf"
	MIMEMSGPACK           = "application/x-msgpack"
	MIMEMSGPACK2          = "application/msgpack"
	MIMEYAML              = "application/x-yaml"
	MIMEYAMLK8s           = "application/x-yaml-k8s"
)

Content-Type MIME of the most common data formats.

Variables

var (
	JSON          = jsonBinding{}
	XML           = xmlBinding{}
	Form          = formBinding{}
	Query         = queryBinding{}
	FormPost      = formPostBinding{}
	FormMultipart = formMultipartBinding{}
	ProtoBuf      = protobufBinding{}
	MsgPack       = msgpackBinding{}
	YAML          = yamlBinding{}
	Uri           = uriBinding{}
	Header        = headerBinding{}
)

These implement the Binding interface and can be used to bind the data present in the request to struct instances.

var (

	// ErrConvertMapStringSlice can not covert to map[string][]string
	ErrConvertMapStringSlice = errors.New("can not convert to map slices of strings")

	// ErrConvertToMapString can not convert to map[string]string
	ErrConvertToMapString = errors.New("can not convert to map of strings")
)

var (
	// ErrMultiFileHeader multipart.FileHeader invalid
	ErrMultiFileHeader = errors.New("unsupported field type for multipart.FileHeader")

	// ErrMultiFileHeaderLenInvalid array for []*multipart.FileHeader len invalid
	ErrMultiFileHeaderLenInvalid = errors.New("unsupported len of array for []*multipart.FileHeader")
)

var EnableDecoderDisallowUnknownFields = false

EnableDecoderDisallowUnknownFields is used to call the DisallowUnknownFields method on the JSON Decoder instance. DisallowUnknownFields causes the Decoder to return an error when the destination is a struct and the input contains object keys which do not match any non-ignored, exported fields in the destination.

var EnableDecoderUseNumber = false

EnableDecoderUseNumber is used to call the UseNumber method on the JSON Decoder instance. UseNumber causes the Decoder to unmarshal a number into an interface{} as a Number instead of as a float64.

Functions

func Bind

func Bind(req *http.Request, obj interface{}) error

Bind checks the Method and Content-Type to select a binding engine automatically, Depending on the "Content-Type" header different bindings are used, for example:

"application/json" --> JSON binding
"application/xml"  --> XML binding

It parses the request's body as JSON if Content-Type == "application/json" using JSON or XML as a JSON input. It decodes the json payload into the struct specified as a pointer.

func MapFormWithTag

func MapFormWithTag(ptr interface{}, form map[string][]string, tag string) error

Types

type Binding

type Binding interface {
	Name() string
	Bind(*http.Request, interface{}) error
}

Binding describes the interface which needs to be implemented for binding the data present in the request such as JSON request body, query parameters or the form POST.

func Default

func Default(method, contentType string) Binding

Default returns the appropriate Binding instance based on the HTTP method and the content type.

type BindingBody

type BindingBody interface {
	Binding
	BindBody([]byte, interface{}) error
}

BindingBody adds BindBody method to Binding. BindBody is similar with Bind, but it reads the body from supplied bytes instead of req.Body.

type BindingUri

type BindingUri interface {
	Name() string
	BindUri(map[string][]string, interface{}) error
}

BindingUri adds BindUri method to Binding. BindUri is similar with Bind, but it reads the Params.

type SliceValidationError

type SliceValidationError []error

func (SliceValidationError) Error

func (err SliceValidationError) Error() string

Error concatenates all error elements in SliceValidationError into a single string separated by \n.

type StructValidator

type StructValidator interface {
	// ValidateStruct can receive any kind of type and it should never panic, even if the configuration is not right.
	// If the received type is a slice|array, the validation should be performed travel on every element.
	// If the received type is not a struct or slice|array, any validation should be skipped and nil must be returned.
	// If the received type is a struct or pointer to a struct, the validation should be performed.
	// If the struct is not valid or the validation itself fails, a descriptive error should be returned.
	// Otherwise nil must be returned.
	ValidateStruct(interface{}) error

	// Engine returns the underlying validator engine which powers the
	// StructValidator implementation.
	Engine() interface{}
}

StructValidator is the minimal interface which needs to be implemented in order for it to be used as the validator engine for ensuring the correctness of the request. Gin provides a default implementation for this using https://github.com/go-playground/validator/tree/v10.6.1.

var Validator StructValidator = &defaultValidator{}

Validator is the default validator which implements the StructValidator interface. It uses https://github.com/go-playground/validator/tree/v10.6.1 under the hood.