This gives you a basic understanding of Procyon Web Module. It covers components provided by the framework, such as Controller, Handler Registry, Web Request Context and Interceptors.
Note that you need to register your components by using the function core.Register.
It's used to define a struct as a Controller Component and register handler methods. If it is implemented by your struct, your struct will be considered as a Controller.
type Controller interface {
RegisterHandlers(registry HandlerRegistry)
}It's used to register handler methods.
type HandlerRegistry interface {
Register(info ...RequestHandler)
RegisterGroup(prefix string, info ...RequestHandler)
}-
Register is used to register a Request Handler.
-
RegisterGroup are used to register multiple Request Handlers.
They are used to get an instance of a request handler by request method.
func Get(handler RequestHandlerFunction, options ...RequestHandlerOption) RequestHandler
func Post(handler RequestHandlerFunction, options ...RequestHandlerOption) RequestHandler
func Put(handler RequestHandlerFunction, options ...RequestHandlerOption) RequestHandler
func Delete(handler RequestHandlerFunction, options ...RequestHandlerOption) RequestHandler
func Patch(handler RequestHandlerFunction, options ...RequestHandlerOption) RequestHandler
func Options(handler RequestHandlerFunction, options ...RequestHandlerOption) RequestHandler
func Head(handler RequestHandlerFunction, options ...RequestHandlerOption) RequestHandlerOptions are used to specify handler's properties like Path and Request Object.
func RequestObject(requestObject RequestHandlerObject) RequestHandlerOption
func Path(path string) RequestHandlerOption- RequestObject is used to specify the request object. If you have a request type, you have to register it. Otherwise, GetRequest will throw an error.
- Path is used to specify the path.
WebRequestContext implements the interface context.Context in procyon-context. That's why it has the methods the following.
func (ctx *WebRequestContext) GetContextId() context.ContextId
func (ctx *WebRequestContext) Get(key string) interface{}
func (ctx *WebRequestContext) Put(key string, value interface{})- GetContextId returns a Context Id. It is unique and consists of UUID. It can be used for logging.
- Get returns the value from context by the given key. If it is not found, it returns nil.
- Put an key-value pair into context.
func (ctx *WebRequestContext) Next()- Next can only be invoked from HandleBefore. If you call it from other methods or functions, nothing will happen. When Next is invoked, it calls next interceptor implementing HandlerInterceptorBefore.
func (ctx *WebRequestContext) GetRequest(request interface{})
func (ctx *WebRequestContext) GetPathVariable(name string) string
func (ctx *WebRequestContext) GetRequestParameter(name string) string
func (ctx *WebRequestContext) GetHeaderValue(key string) string- GetRequest is used to bind the request data to the instance of the request object.
- GetPathVariable is used to get the path variable by name
- GetRequestParameter is used to get the request parameter by name.
- GetHeaderValue is used to get the header value by name.
func (ctx *WebRequestContext) GetStatus() int
func (ctx *WebRequestContext) SetStatus(status int) ResponseBodyBuilder
func (ctx *WebRequestContext) SetBody(body interface{}) ResponseBodyBuilder
func (ctx *WebRequestContext) GetBody() interface{}
func (ctx *WebRequestContext) GetContentType() MediaType
func (ctx *WebRequestContext) SetContentType(mediaType MediaType) ResponseBodyBuilder
func (ctx *WebRequestContext) AddHeader(key string, value string) ResponseHeaderBuilder- GetStatus is used to get the status.
- SetStatus is used to set the status of response.
- SetBody is used to set the body of response.
- GetBody is used to get the body of response.
- GetContentType is used to get the content type.
- SetContentType is used to set the content type
func (ctx *WebRequestContext) Ok() ResponseBodyBuilder
func (ctx *WebRequestContext) NotFound() ResponseHeaderBuilder
func (ctx *WebRequestContext) NoContent() ResponseHeaderBuilder
func (ctx *WebRequestContext) BadRequest() ResponseBodyBuilder
func (ctx *WebRequestContext) Accepted() ResponseBodyBuilder
func (ctx *WebRequestContext) Created(location string) ResponseBodyBuilder- Ok sets the status to 200.
- NotFound sets the status to 404.
- NoContent sets the status to 204.
- BadRequest sets the status to 400.
- Accepted sets the status to 202.
- Created sets the status to 201.
func (ctx *WebRequestContext) GetError() error
func (ctx *WebRequestContext) SetError(err error)
func (ctx *WebRequestContext) ThrowError(err error)- GetError is used to get the error.
- SetError is used to put the error into context.
- ThrowError is used to throw an error. It's an alternative to SetError
Interceptors are used to manipulate requests and responses.
HandlerBefore,Handler Method and HandlerAfter, HandleAfterCompletion are invoked respectively.
If you want to do something before handler method is executed, implement the interface HandlerInterceptorBefore.
type HandlerInterceptorBefore interface {
HandleBefore(requestContext *WebRequestContext)
}If you want to do something after handler method is executed, implement the interface HandlerInterceptorAfter.
type HandlerInterceptorAfter interface {
HandleAfter(requestContext *WebRequestContext)
}If you want to do something after the request process is completed, implement the interface HandlerInterceptorAfterCompletion. HandlerAfterCompletion is invoked after response is returned successfully or when any error occurs while request is processed. In case of an error, You can get the error from request context.
type HandlerInterceptorAfterCompletion interface {
HandleAfterCompletion(requestContext *WebRequestContext)
}Procyon Framework is released under version 2.0 of the Apache License