README
¶
Negotiator 
This is a libary that handles content negotiation in web applications written in Go.
Usage
Simple
To return JSON/XML out of the box simple put this in your route handler:
func getUser(w http.ResponseWriter, req *http.Request) {
user := &User{"Joe","Bloggs"}
if err := negotiator.Negotiate(w, req, user); err != nil {
http.Error(w, err.Error(), http.StatusInternalServerError)
}
}
Custom
To add your own negotiator, for example you want to write a PDF with your model, do the following:
-
Create a type that conforms to the ResponseProcessor interface
-
Call
negotiator.New(responseProcessors ...ResponseProcessor)and pass in a your custom processor. When your request handler callsnegotiator.Negotiate(w,req,model,errorHandler)it will render a PDF if your Accept header defined it wanted a PDF response.
Documentation
¶
Overview ¶
Package negotiator is a library that handles content negotiation in web applications written in Go. Content negotiation is specified by RFC (http://tools.ietf.org/html/rfc7231) and, less formally, by Ajax (https://en.wikipedia.org/wiki/XMLHttpRequest).
A Negotiator contains a list of ResponseProcessor. For each call to Negotiate, the best matching response processor is chosen and given the task of sending the response.
For more information visit http://github.com/jchannon/negotiator
func getUser(w http.ResponseWriter, req *http.Request) {
user := &User{"Joe", "Bloggs"}
negotiator.Negotiate(w, req, user)
}
Index ¶
- Constants
- func IsAjax(req *http.Request) bool
- func Negotiate(w http.ResponseWriter, req *http.Request, dataModel interface{}, ...) error
- type AjaxResponseProcessor
- type ContentTypeSettable
- type Negotiator
- type ResponseProcessor
- func NewCSV(comma ...rune) ResponseProcessor
- func NewJSON() ResponseProcessor
- func NewJSONIndent(prefix, index string) ResponseProcessor
- func NewJSONIndent2Spaces() ResponseProcessor
- func NewTXT() ResponseProcessor
- func NewXML() ResponseProcessor
- func NewXMLIndent(prefix, index string) ResponseProcessor
- func NewXMLIndent2Spaces() ResponseProcessor
Constants ¶
const ( // ParameteredMediaRangeWeight is the default weight of a media range with an // accept-param ParameteredMediaRangeWeight float64 = 1.0 //e.g text/html;level=1 // TypeSubtypeMediaRangeWeight is the default weight of a media range with // type and subtype defined TypeSubtypeMediaRangeWeight float64 = 0.9 //e.g text/html // TypeStarMediaRangeWeight is the default weight of a media range with a type // defined but * for subtype TypeStarMediaRangeWeight float64 = 0.8 //e.g text/* // StarStarMediaRangeWeight is the default weight of a media range with any // type or any subtype defined StarStarMediaRangeWeight float64 = 0.7 //e.g */* )
Variables ¶
This section is empty.
Functions ¶
Types ¶
type AjaxResponseProcessor ¶
type AjaxResponseProcessor interface {
IsAjaxResponder() bool
}
AjaxResponseProcessor interface allows content negotiation to be biased when Ajax requests are handled. If a ResponseProcessor also implements this interface and its method returns true, then all Ajax requests will be fulfilled by that request processor, instead of via the normal content negotiation.
type ContentTypeSettable ¶
type ContentTypeSettable interface {
SetContentType(contentType string) ResponseProcessor
}
ContentTypeSettable interface provides for those response processors that allow the response Content-Type to be set explicitly.
type Negotiator ¶
type Negotiator struct {
// contains filtered or unexported fields
}
Negotiator is responsible for content negotiation when using custom response processors.
func New ¶
func New(responseProcessors ...ResponseProcessor) *Negotiator
New allows users to pass custom response processors.
func NewWithJSONAndXML ¶
func NewWithJSONAndXML(responseProcessors ...ResponseProcessor) *Negotiator
NewWithJSONAndXML allows users to pass custom response processors. By default, processors for XML and JSON are already created.
func (*Negotiator) Add ¶
func (n *Negotiator) Add(responseProcessors ...ResponseProcessor) *Negotiator
Add more response processors. A new Negotiator is returned with the original processors plus the extra processors.
func (*Negotiator) Negotiate ¶
func (n *Negotiator) Negotiate(w http.ResponseWriter, req *http.Request, dataModel interface{}, context ...interface{}) error
Negotiate your model based on the HTTP Accept header.
type ResponseProcessor ¶
type ResponseProcessor interface {
CanProcess(mediaRange string) bool
Process(w http.ResponseWriter, req *http.Request, dataModel interface{}, context ...interface{}) error
}
ResponseProcessor interface creates the contract for custom content negotiation.
func NewCSV ¶
func NewCSV(comma ...rune) ResponseProcessor
NewCSV creates an output processor that serialises a dataModel in CSV form. With no arguments, the default format is comma-separated; you can supply any rune to be used as an alternative separator.
Model values should be one of the following:
* string or []string, or [][]string
* fmt.Stringer or []fmt.Stringer, or [][]fmt.Stringer
* []int or similar (bool, int8, int16, int32, int64, uint8, uint16, uint32, uint63, float32, float64, complex)
* [][]int or similar (bool, int8, int16, int32, int64, uint8, uint16, uint32, uint63, float32, float64, complex)
* struct for some struct in which all the fields are exported and of simple types (as above).
* []struct for some struct in which all the fields are exported and of simple types (as above).
func NewJSON ¶
func NewJSON() ResponseProcessor
NewJSON creates a new processor for JSON without indentation.
func NewJSONIndent ¶
func NewJSONIndent(prefix, index string) ResponseProcessor
NewJSONIndent creates a new processor for JSON with a specified indentation.
func NewJSONIndent2Spaces ¶
func NewJSONIndent2Spaces() ResponseProcessor
NewJSONIndent2Spaces creates a new processor for JSON with 2-space indentation.
func NewTXT ¶
func NewTXT() ResponseProcessor
NewTXT creates an output processor that serialises strings in text/plain form. Model values should be one of the following:
* string
* fmt.Stringer
* encoding.TextMarshaler
func NewXML ¶
func NewXML() ResponseProcessor
NewXML creates a new processor for XML without indentation.
func NewXMLIndent ¶
func NewXMLIndent(prefix, index string) ResponseProcessor
NewXMLIndent creates a new processor for XML with a specified indentation.
func NewXMLIndent2Spaces ¶
func NewXMLIndent2Spaces() ResponseProcessor
NewXMLIndent2Spaces creates a new processor for XML with 2-space indentation.
Source Files