|
|
package restful
|
|
|
|
|
|
// Copyright 2013 Ernest Micklei. All rights reserved.
|
|
|
// Use of this source code is governed by a license
|
|
|
// that can be found in the LICENSE file.
|
|
|
|
|
|
import (
|
|
|
"bytes"
|
|
|
"errors"
|
|
|
"fmt"
|
|
|
"net/http"
|
|
|
"os"
|
|
|
"runtime"
|
|
|
"strings"
|
|
|
"sync"
|
|
|
|
|
|
"github.com/emicklei/go-restful/log"
|
|
|
)
|
|
|
|
|
|
// Container holds a collection of WebServices and a http.ServeMux to dispatch http requests.
|
|
|
// The requests are further dispatched to routes of WebServices using a RouteSelector
|
|
|
type Container struct {
|
|
|
webServicesLock sync.RWMutex
|
|
|
webServices []*WebService
|
|
|
ServeMux *http.ServeMux
|
|
|
isRegisteredOnRoot bool
|
|
|
containerFilters []FilterFunction
|
|
|
doNotRecover bool // default is false
|
|
|
recoverHandleFunc RecoverHandleFunction
|
|
|
serviceErrorHandleFunc ServiceErrorHandleFunction
|
|
|
router RouteSelector // default is a RouterJSR311, CurlyRouter is the faster alternative
|
|
|
contentEncodingEnabled bool // default is false
|
|
|
}
|
|
|
|
|
|
// NewContainer creates a new Container using a new ServeMux and default router (RouterJSR311)
|
|
|
func NewContainer() *Container {
|
|
|
return &Container{
|
|
|
webServices: []*WebService{},
|
|
|
ServeMux: http.NewServeMux(),
|
|
|
isRegisteredOnRoot: false,
|
|
|
containerFilters: []FilterFunction{},
|
|
|
doNotRecover: false,
|
|
|
recoverHandleFunc: logStackOnRecover,
|
|
|
serviceErrorHandleFunc: writeServiceError,
|
|
|
router: RouterJSR311{},
|
|
|
contentEncodingEnabled: false}
|
|
|
}
|
|
|
|
|
|
// RecoverHandleFunction declares functions that can be used to handle a panic situation.
|
|
|
// The first argument is what recover() returns. The second must be used to communicate an error response.
|
|
|
type RecoverHandleFunction func(interface{}, http.ResponseWriter)
|
|
|
|
|
|
// RecoverHandler changes the default function (logStackOnRecover) to be called
|
|
|
// when a panic is detected. DoNotRecover must be have its default value (=false).
|
|
|
func (c *Container) RecoverHandler(handler RecoverHandleFunction) {
|
|
|
c.recoverHandleFunc = handler
|
|
|
}
|
|
|
|
|
|
// ServiceErrorHandleFunction declares functions that can be used to handle a service error situation.
|
|
|
// The first argument is the service error, the second is the request that resulted in the error and
|
|
|
// the third must be used to communicate an error response.
|
|
|
type ServiceErrorHandleFunction func(ServiceError, *Request, *Response)
|
|
|
|
|
|
// ServiceErrorHandler changes the default function (writeServiceError) to be called
|
|
|
// when a ServiceError is detected.
|
|
|
func (c *Container) ServiceErrorHandler(handler ServiceErrorHandleFunction) {
|
|
|
c.serviceErrorHandleFunc = handler
|
|
|
}
|
|
|
|
|
|
// DoNotRecover controls whether panics will be caught to return HTTP 500.
|
|
|
// If set to true, Route functions are responsible for handling any error situation.
|
|
|
// Default value is false = recover from panics. This has performance implications.
|
|
|
func (c *Container) DoNotRecover(doNot bool) {
|
|
|
c.doNotRecover = doNot
|
|
|
}
|
|
|
|
|
|
// Router changes the default Router (currently RouterJSR311)
|
|
|
func (c *Container) Router(aRouter RouteSelector) {
|
|
|
c.router = aRouter
|
|
|
}
|
|
|
|
|
|
// EnableContentEncoding (default=false) allows for GZIP or DEFLATE encoding of responses.
|
|
|
func (c *Container) EnableContentEncoding(enabled bool) {
|
|
|
c.contentEncodingEnabled = enabled
|
|
|
}
|
|
|
|
|
|
// Add a WebService to the Container. It will detect duplicate root paths and exit in that case.
|
|
|
func (c *Container) Add(service *WebService) *Container {
|
|
|
c.webServicesLock.Lock()
|
|
|
defer c.webServicesLock.Unlock()
|
|
|
|
|
|
// if rootPath was not set then lazy initialize it
|
|
|
if len(service.rootPath) == 0 {
|
|
|
service.Path("/")
|
|
|
}
|
|
|
|
|
|
// cannot have duplicate root paths
|
|
|
for _, each := range c.webServices {
|
|
|
if each.RootPath() == service.RootPath() {
|
|
|
log.Printf("[restful] WebService with duplicate root path detected:['%v']", each)
|
|
|
os.Exit(1)
|
|
|
}
|
|
|
}
|
|
|
|
|
|
// If not registered on root then add specific mapping
|
|
|
if !c.isRegisteredOnRoot {
|
|
|
c.isRegisteredOnRoot = c.addHandler(service, c.ServeMux)
|
|
|
}
|
|
|
c.webServices = append(c.webServices, service)
|
|
|
return c
|
|
|
}
|
|
|
|
|
|
// addHandler may set a new HandleFunc for the serveMux
|
|
|
// this function must run inside the critical region protected by the webServicesLock.
|
|
|
// returns true if the function was registered on root ("/")
|
|
|
func (c *Container) addHandler(service *WebService, serveMux *http.ServeMux) bool {
|
|
|
pattern := fixedPrefixPath(service.RootPath())
|
|
|
// check if root path registration is needed
|
|
|
if "/" == pattern || "" == pattern {
|
|
|
serveMux.HandleFunc("/", c.dispatch)
|
|
|
return true
|
|
|
}
|
|
|
// detect if registration already exists
|
|
|
alreadyMapped := false
|
|
|
for _, each := range c.webServices {
|
|
|
if each.RootPath() == service.RootPath() {
|
|
|
alreadyMapped = true
|
|
|
break
|
|
|
}
|
|
|
}
|
|
|
if !alreadyMapped {
|
|
|
serveMux.HandleFunc(pattern, c.dispatch)
|
|
|
if !strings.HasSuffix(pattern, "/") {
|
|
|
serveMux.HandleFunc(pattern+"/", c.dispatch)
|
|
|
}
|
|
|
}
|
|
|
return false
|
|
|
}
|
|
|
|
|
|
func (c *Container) Remove(ws *WebService) error {
|
|
|
if c.ServeMux == http.DefaultServeMux {
|
|
|
errMsg := fmt.Sprintf("[restful] cannot remove a WebService from a Container using the DefaultServeMux: ['%v']", ws)
|
|
|
log.Printf(errMsg)
|
|
|
return errors.New(errMsg)
|
|
|
}
|
|
|
c.webServicesLock.Lock()
|
|
|
defer c.webServicesLock.Unlock()
|
|
|
// build a new ServeMux and re-register all WebServices
|
|
|
newServeMux := http.NewServeMux()
|
|
|
newServices := []*WebService{}
|
|
|
newIsRegisteredOnRoot := false
|
|
|
for _, each := range c.webServices {
|
|
|
if each.rootPath != ws.rootPath {
|
|
|
// If not registered on root then add specific mapping
|
|
|
if !newIsRegisteredOnRoot {
|
|
|
newIsRegisteredOnRoot = c.addHandler(each, newServeMux)
|
|
|
}
|
|
|
newServices = append(newServices, each)
|
|
|
}
|
|
|
}
|
|
|
c.webServices, c.ServeMux, c.isRegisteredOnRoot = newServices, newServeMux, newIsRegisteredOnRoot
|
|
|
return nil
|
|
|
}
|
|
|
|
|
|
// logStackOnRecover is the default RecoverHandleFunction and is called
|
|
|
// when DoNotRecover is false and the recoverHandleFunc is not set for the container.
|
|
|
// Default implementation logs the stacktrace and writes the stacktrace on the response.
|
|
|
// This may be a security issue as it exposes sourcecode information.
|
|
|
func logStackOnRecover(panicReason interface{}, httpWriter http.ResponseWriter) {
|
|
|
var buffer bytes.Buffer
|
|
|
buffer.WriteString(fmt.Sprintf("[restful] recover from panic situation: - %v\r\n", panicReason))
|
|
|
for i := 2; ; i += 1 {
|
|
|
_, file, line, ok := runtime.Caller(i)
|
|
|
if !ok {
|
|
|
break
|
|
|
}
|
|
|
buffer.WriteString(fmt.Sprintf(" %s:%d\r\n", file, line))
|
|
|
}
|
|
|
log.Print(buffer.String())
|
|
|
httpWriter.WriteHeader(http.StatusInternalServerError)
|
|
|
httpWriter.Write(buffer.Bytes())
|
|
|
}
|
|
|
|
|
|
// writeServiceError is the default ServiceErrorHandleFunction and is called
|
|
|
// when a ServiceError is returned during route selection. Default implementation
|
|
|
// calls resp.WriteErrorString(err.Code, err.Message)
|
|
|
func writeServiceError(err ServiceError, req *Request, resp *Response) {
|
|
|
resp.WriteErrorString(err.Code, err.Message)
|
|
|
}
|
|
|
|
|
|
// Dispatch the incoming Http Request to a matching WebService.
|
|
|
func (c *Container) dispatch(httpWriter http.ResponseWriter, httpRequest *http.Request) {
|
|
|
writer := httpWriter
|
|
|
|
|
|
// CompressingResponseWriter should be closed after all operations are done
|
|
|
defer func() {
|
|
|
if compressWriter, ok := writer.(*CompressingResponseWriter); ok {
|
|
|
compressWriter.Close()
|
|
|
}
|
|
|
}()
|
|
|
|
|
|
// Instal panic recovery unless told otherwise
|
|
|
if !c.doNotRecover { // catch all for 500 response
|
|
|
defer func() {
|
|
|
if r := recover(); r != nil {
|
|
|
c.recoverHandleFunc(r, writer)
|
|
|
return
|
|
|
}
|
|
|
}()
|
|
|
}
|
|
|
// Install closing the request body (if any)
|
|
|
defer func() {
|
|
|
if nil != httpRequest.Body {
|
|
|
httpRequest.Body.Close()
|
|
|
}
|
|
|
}()
|
|
|
|
|
|
// Detect if compression is needed
|
|
|
// assume without compression, test for override
|
|
|
if c.contentEncodingEnabled {
|
|
|
doCompress, encoding := wantsCompressedResponse(httpRequest)
|
|
|
if doCompress {
|
|
|
var err error
|
|
|
writer, err = NewCompressingResponseWriter(httpWriter, encoding)
|
|
|
if err != nil {
|
|
|
log.Print("[restful] unable to install compressor: ", err)
|
|
|
httpWriter.WriteHeader(http.StatusInternalServerError)
|
|
|
return
|
|
|
}
|
|
|
}
|
|
|
}
|
|
|
// Find best match Route ; err is non nil if no match was found
|
|
|
var webService *WebService
|
|
|
var route *Route
|
|
|
var err error
|
|
|
func() {
|
|
|
c.webServicesLock.RLock()
|
|
|
defer c.webServicesLock.RUnlock()
|
|
|
webService, route, err = c.router.SelectRoute(
|
|
|
c.webServices,
|
|
|
httpRequest)
|
|
|
}()
|
|
|
if err != nil {
|
|
|
// a non-200 response has already been written
|
|
|
// run container filters anyway ; they should not touch the response...
|
|
|
chain := FilterChain{Filters: c.containerFilters, Target: func(req *Request, resp *Response) {
|
|
|
switch err.(type) {
|
|
|
case ServiceError:
|
|
|
ser := err.(ServiceError)
|
|
|
c.serviceErrorHandleFunc(ser, req, resp)
|
|
|
}
|
|
|
// TODO
|
|
|
}}
|
|
|
chain.ProcessFilter(NewRequest(httpRequest), NewResponse(writer))
|
|
|
return
|
|
|
}
|
|
|
wrappedRequest, wrappedResponse := route.wrapRequestResponse(writer, httpRequest)
|
|
|
// pass through filters (if any)
|
|
|
if len(c.containerFilters)+len(webService.filters)+len(route.Filters) > 0 {
|
|
|
// compose filter chain
|
|
|
allFilters := []FilterFunction{}
|
|
|
allFilters = append(allFilters, c.containerFilters...)
|
|
|
allFilters = append(allFilters, webService.filters...)
|
|
|
allFilters = append(allFilters, route.Filters...)
|
|
|
chain := FilterChain{Filters: allFilters, Target: func(req *Request, resp *Response) {
|
|
|
// handle request by route after passing all filters
|
|
|
route.Function(wrappedRequest, wrappedResponse)
|
|
|
}}
|
|
|
chain.ProcessFilter(wrappedRequest, wrappedResponse)
|
|
|
} else {
|
|
|
// no filters, handle request by route
|
|
|
route.Function(wrappedRequest, wrappedResponse)
|
|
|
}
|
|
|
}
|
|
|
|
|
|
// fixedPrefixPath returns the fixed part of the partspec ; it may include template vars {}
|
|
|
func fixedPrefixPath(pathspec string) string {
|
|
|
varBegin := strings.Index(pathspec, "{")
|
|
|
if -1 == varBegin {
|
|
|
return pathspec
|
|
|
}
|
|
|
return pathspec[:varBegin]
|
|
|
}
|
|
|
|
|
|
// ServeHTTP implements net/http.Handler therefore a Container can be a Handler in a http.Server
|
|
|
func (c *Container) ServeHTTP(httpwriter http.ResponseWriter, httpRequest *http.Request) {
|
|
|
c.ServeMux.ServeHTTP(httpwriter, httpRequest)
|
|
|
}
|
|
|
|
|
|
// Handle registers the handler for the given pattern. If a handler already exists for pattern, Handle panics.
|
|
|
func (c *Container) Handle(pattern string, handler http.Handler) {
|
|
|
c.ServeMux.Handle(pattern, handler)
|
|
|
}
|
|
|
|
|
|
// HandleWithFilter registers the handler for the given pattern.
|
|
|
// Container's filter chain is applied for handler.
|
|
|
// If a handler already exists for pattern, HandleWithFilter panics.
|
|
|
func (c *Container) HandleWithFilter(pattern string, handler http.Handler) {
|
|
|
f := func(httpResponse http.ResponseWriter, httpRequest *http.Request) {
|
|
|
if len(c.containerFilters) == 0 {
|
|
|
handler.ServeHTTP(httpResponse, httpRequest)
|
|
|
return
|
|
|
}
|
|
|
|
|
|
chain := FilterChain{Filters: c.containerFilters, Target: func(req *Request, resp *Response) {
|
|
|
handler.ServeHTTP(httpResponse, httpRequest)
|
|
|
}}
|
|
|
chain.ProcessFilter(NewRequest(httpRequest), NewResponse(httpResponse))
|
|
|
}
|
|
|
|
|
|
c.Handle(pattern, http.HandlerFunc(f))
|
|
|
}
|
|
|
|
|
|
// Filter appends a container FilterFunction. These are called before dispatching
|
|
|
// a http.Request to a WebService from the container
|
|
|
func (c *Container) Filter(filter FilterFunction) {
|
|
|
c.containerFilters = append(c.containerFilters, filter)
|
|
|
}
|
|
|
|
|
|
// RegisteredWebServices returns the collections of added WebServices
|
|
|
func (c *Container) RegisteredWebServices() []*WebService {
|
|
|
c.webServicesLock.RLock()
|
|
|
defer c.webServicesLock.RUnlock()
|
|
|
result := make([]*WebService, len(c.webServices))
|
|
|
for ix := range c.webServices {
|
|
|
result[ix] = c.webServices[ix]
|
|
|
}
|
|
|
return result
|
|
|
}
|
|
|
|
|
|
// computeAllowedMethods returns a list of HTTP methods that are valid for a Request
|
|
|
func (c *Container) computeAllowedMethods(req *Request) []string {
|
|
|
// Go through all RegisteredWebServices() and all its Routes to collect the options
|
|
|
methods := []string{}
|
|
|
requestPath := req.Request.URL.Path
|
|
|
for _, ws := range c.RegisteredWebServices() {
|
|
|
matches := ws.pathExpr.Matcher.FindStringSubmatch(requestPath)
|
|
|
if matches != nil {
|
|
|
finalMatch := matches[len(matches)-1]
|
|
|
for _, rt := range ws.Routes() {
|
|
|
matches := rt.pathExpr.Matcher.FindStringSubmatch(finalMatch)
|
|
|
if matches != nil {
|
|
|
lastMatch := matches[len(matches)-1]
|
|
|
if lastMatch == "" || lastMatch == "/" { // do not include if value is neither empty nor ‘/’.
|
|
|
methods = append(methods, rt.Method)
|
|
|
}
|
|
|
}
|
|
|
}
|
|
|
}
|
|
|
}
|
|
|
// methods = append(methods, "OPTIONS") not sure about this
|
|
|
return methods
|
|
|
}
|
|
|
|
|
|
// newBasicRequestResponse creates a pair of Request,Response from its http versions.
|
|
|
// It is basic because no parameter or (produces) content-type information is given.
|
|
|
func newBasicRequestResponse(httpWriter http.ResponseWriter, httpRequest *http.Request) (*Request, *Response) {
|
|
|
resp := NewResponse(httpWriter)
|
|
|
resp.requestAccept = httpRequest.Header.Get(HEADER_Accept)
|
|
|
return NewRequest(httpRequest), resp
|
|
|
}
|
