// Creates a response from a handler and a request.
//
// It calls the handler's ServeHTTP method with an internal response
// writer that shares the status code, headers and the response body
// with the returned response. It blocks until the handler calls the
// response writer's WriteHeader, or starts writing the body, or
// returns. The written body is not buffered, but piped to the returned
// response's body.
//
// Example, a simple file server:
//
// var handler = http.StripPrefix(webRoot, http.FileServer(http.Dir(root)))
//
// func (f *myFilter) Request(ctx filters.FilterContext) {
// serve.ServeHTTP(ctx, handler)
// }
//
func ServeHTTP(ctx filters.FilterContext, h http.Handler) {
rsp := &http.Response{Header: make(http.Header)}
r, w := io.Pipe()
d := &pipedResponse{
response: rsp,
reader: r,
writer: w,
headerDone: make(chan struct{})}
req := ctx.Request()
go func() {
h.ServeHTTP(d, req)
select {
case <-d.headerDone:
default:
d.WriteHeader(http.StatusOK)
}
w.CloseWithError(io.EOF)
}()
<-d.headerDone
rsp.Body = d
ctx.Serve(rsp)
}
// Sets the status code and the location header of the response. Marks the
// request served.
func (f *redirect) Response(ctx filters.FilterContext) {
r := ctx.Request()
w := ctx.ResponseWriter()
u := f.copyOfLocation()
if u.Scheme == "" {
if r.URL.Scheme != "" {
u.Scheme = r.URL.Scheme
} else {
u.Scheme = "https"
}
}
u.User = r.URL.User
if u.Host == "" {
u.Host = getRequestHost(r)
}
if u.Path == "" {
u.Path = r.URL.Path
}
if u.RawQuery == "" {
u.RawQuery = r.URL.RawQuery
}
w.Header().Set("Location", u.String())
w.WriteHeader(f.code)
ctx.MarkServed()
}
// Strips the query parameters and optionally preserves them in the X-Query-Param-xyz headers.
func (f *stripQuery) Request(ctx filters.FilterContext) {
r := ctx.Request()
if r == nil {
return
}
url := r.URL
if url == nil {
return
}
if !f.preserveAsHeader {
url.RawQuery = ""
return
}
q := url.Query()
for k, vv := range q {
for _, v := range vv {
if r.Header == nil {
r.Header = http.Header{}
}
r.Header.Add(fmt.Sprintf("X-Query-Param-%s", sanitize(k)), v)
}
}
url.RawQuery = ""
}
func getLocation(ctx filters.FilterContext, location *url.URL) string {
r := ctx.Request()
uc := *location
u := &uc
if u.Scheme == "" {
if r.URL.Scheme != "" {
u.Scheme = r.URL.Scheme
} else {
u.Scheme = "https"
}
}
u.User = r.URL.User
if u.Host == "" {
u.Host = getRequestHost(r)
}
if u.Path == "" {
u.Path = r.URL.Path
}
if u.RawQuery == "" {
u.RawQuery = r.URL.RawQuery
}
return u.String()
}
func (t *throttle) Request(ctx filters.FilterContext) {
switch t.typ {
case latency, bandwidth, chunks:
return
}
req := ctx.Request()
req.Body = t.goThrottle(req.Body, false)
}
func (f *headerFilter) Request(ctx filters.FilterContext) {
if f.typ != requestHeader {
return
}
ctx.Request().Header.Add(f.key, f.value)
if strings.ToLower(f.key) == "host" {
ctx.SetOutgoingHost(f.value)
}
}
func (f *headerFilter) Request(ctx filters.FilterContext) {
if f.typ == requestHeader {
req := ctx.Request()
if strings.ToLower(f.key) == "host" {
req.Host = f.value
}
req.Header.Add(f.key, f.value)
}
}
// Serves content from the file system and marks the request served.
func (f *static) Response(ctx filters.FilterContext) {
r := ctx.Request()
p := r.URL.Path
if len(p) < len(f.webRoot) {
return
}
ctx.MarkServed()
http.ServeFile(ctx.ResponseWriter(), ctx.Request(), path.Join(f.root, p[len(f.webRoot):]))
}
// Request is copied and then modified to adopt changes in new backend
func (r *tee) Request(fc filters.FilterContext) {
copyOfRequest := cloneRequest(r, fc.Request())
go func() {
rsp, err := r.client.Do(©OfRequest)
if err != nil {
log.Warn("error while tee request", err)
}
if err == nil {
defer rsp.Body.Close()
}
}()
}
func (preserve filter) Request(ctx filters.FilterContext) {
u, err := url.Parse(ctx.BackendUrl())
if err != nil {
log.Error("failed to parse backend host in preserveHost filter", err)
return
}
if preserve && ctx.OutgoingHost() == u.Host {
ctx.SetOutgoingHost(ctx.Request().Host)
} else if !preserve && ctx.OutgoingHost() == ctx.Request().Host {
ctx.SetOutgoingHost(u.Host)
}
}
// check basic auth
func (a *basic) Request(ctx filters.FilterContext) {
username := a.authenticator.CheckAuth(ctx.Request())
if username == "" {
header := http.Header{}
header.Set(ForceBasicAuthHeaderName, a.realmDefinition)
ctx.Serve(&http.Response{
StatusCode: http.StatusUnauthorized,
Header: header,
})
}
}
func (c *compress) Response(ctx filters.FilterContext) {
rsp := ctx.Response()
if !canEncodeEntity(rsp, c.mime) {
return
}
enc := acceptedEncoding(ctx.Request())
if enc == "" {
return
}
responseHeader(rsp, enc)
responseBody(rsp, enc, c.level)
}
func (f *flowId) Request(fc filters.FilterContext) {
r := fc.Request()
var flowId string
if f.reuseExisting {
flowId = r.Header.Get(HeaderName)
if isValid(flowId) {
return
}
}
flowId, err := NewFlowId(f.flowIdLength)
if err == nil {
r.Header.Set(HeaderName, flowId)
} else {
log.Println(err)
}
}
func (f *headerFilter) Request(ctx filters.FilterContext) {
switch f.typ {
case setRequestHeader:
ctx.Request().Header.Set(f.key, f.value)
if strings.ToLower(f.key) == "host" {
ctx.SetOutgoingHost(f.value)
}
case appendRequestHeader, depRequestHeader:
ctx.Request().Header.Add(f.key, f.value)
if strings.ToLower(f.key) == "host" {
ctx.SetOutgoingHost(f.value)
}
case dropRequestHeader:
ctx.Request().Header.Del(f.key)
}
}
func (rc *requestCheck) Request(ctx filters.FilterContext) {
if !rc.check(ctx.Request()) {
ctx.Serve(&http.Response{StatusCode: http.StatusBadRequest})
}
}
func (corf *preserveOriginalFilter) Request(ctx filters.FilterContext) {
preserveHeader(ctx.OriginalRequest().Header, ctx.Request().Header)
}
// the filter copies the path parameter 'echo' to the 'X-Echo' header
func (f *setEchoHeader) Request(ctx filters.FilterContext) {
ctx.Request().Header.Set("X-Echo", ctx.PathParam("echo"))
}
// Modifies the path with regexp.ReplaceAll.
func (f *modPath) Request(ctx filters.FilterContext) {
req := ctx.Request()
req.URL.Path = string(f.rx.ReplaceAll([]byte(req.URL.Path), f.replacement))
}
// a simple filter logging the request URLs
func (f *customFilter) Request(ctx filters.FilterContext) {
log.Println(f.prefix, ctx.Request().URL)
}