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author | Matthew Heon <matthew.heon@gmail.com> | 2017-11-01 11:24:59 -0400 |
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committer | Matthew Heon <matthew.heon@gmail.com> | 2017-11-01 11:24:59 -0400 |
commit | a031b83a09a8628435317a03f199cdc18b78262f (patch) | |
tree | bc017a96769ce6de33745b8b0b1304ccf38e9df0 /vendor/github.com/emicklei/go-restful/container.go | |
parent | 2b74391cd5281f6fdf391ff8ad50fd1490f6bf89 (diff) | |
download | podman-a031b83a09a8628435317a03f199cdc18b78262f.tar.gz podman-a031b83a09a8628435317a03f199cdc18b78262f.tar.bz2 podman-a031b83a09a8628435317a03f199cdc18b78262f.zip |
Initial checkin from CRI-O repo
Signed-off-by: Matthew Heon <matthew.heon@gmail.com>
Diffstat (limited to 'vendor/github.com/emicklei/go-restful/container.go')
-rw-r--r-- | vendor/github.com/emicklei/go-restful/container.go | 366 |
1 files changed, 366 insertions, 0 deletions
diff --git a/vendor/github.com/emicklei/go-restful/container.go b/vendor/github.com/emicklei/go-restful/container.go new file mode 100644 index 000000000..657d5b6dd --- /dev/null +++ b/vendor/github.com/emicklei/go-restful/container.go @@ -0,0 +1,366 @@ +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 true + recoverHandleFunc RecoverHandleFunction + serviceErrorHandleFunc ServiceErrorHandleFunction + router RouteSelector // default is a CurlyRouter (RouterJSR311 is a slower alternative) + contentEncodingEnabled bool // default is false +} + +// NewContainer creates a new Container using a new ServeMux and default router (CurlyRouter) +func NewContainer() *Container { + return &Container{ + webServices: []*WebService{}, + ServeMux: http.NewServeMux(), + isRegisteredOnRoot: false, + containerFilters: []FilterFunction{}, + doNotRecover: true, + recoverHandleFunc: logStackOnRecover, + serviceErrorHandleFunc: writeServiceError, + router: CurlyRouter{}, + 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 true. +func (c *Container) DoNotRecover(doNot bool) { + c.doNotRecover = doNot +} + +// Router changes the default Router (currently CurlyRouter) +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) { + if httpWriter == nil { + panic("httpWriter cannot be nil") + } + if httpRequest == nil { + panic("httpRequest cannot be nil") + } + c.dispatch(httpWriter, httpRequest) +} + +// 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 + } + }() + } + + // 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 +} |