func (t *transaction) Respond(status int, header web.Header) (body io.Writer) {
if t.hijacked {
log.Println("twister: Respond called on hijacked connection")
return &nullResponseBody{err: web.ErrInvalidState}
}
if t.respondCalled {
log.Println("twister: Multiple calls to Respond")
return &nullResponseBody{err: web.ErrInvalidState}
}
t.respondCalled = true
t.requestErr = web.ErrInvalidState
t.status = status
t.header = header
if te := header.Get(web.HeaderTransferEncoding); te != "" {
log.Println("twister: transfer encoding not allowed")
delete(header, web.HeaderTransferEncoding)
}
if !t.requestConsumed {
t.closeAfterResponse = true
}
if header.Get(web.HeaderConnection) == "close" {
t.closeAfterResponse = true
}
t.chunkedResponse = true
contentLength := -1
if status == web.StatusNotModified {
delete(header, web.HeaderContentType)
delete(header, web.HeaderContentLength)
t.chunkedResponse = false
} else if s := header.Get(web.HeaderContentLength); s != "" {
contentLength, _ = strconv.Atoi(s)
t.chunkedResponse = false
} else if t.req.ProtocolVersion < web.ProtocolVersion(1, 1) {
t.closeAfterResponse = true
}
if t.closeAfterResponse {
header.Set(web.HeaderConnection, "close")
t.chunkedResponse = false
}
if t.req.Method == "HEAD" {
t.chunkedResponse = false
}
if t.chunkedResponse {
header.Set(web.HeaderTransferEncoding, "chunked")
}
proto := "HTTP/1.0"
if t.req.ProtocolVersion >= web.ProtocolVersion(1, 1) {
proto = "HTTP/1.1"
}
statusString := strconv.Itoa(status)
text := web.StatusText(status)
var b bytes.Buffer
b.WriteString(proto)
b.WriteString(" ")
b.WriteString(statusString)
b.WriteString(" ")
b.WriteString(text)
b.WriteString("\r\n")
header.WriteHttpHeader(&b)
t.headerSize = b.Len()
const bufferSize = 4096
switch {
case t.req.Method == "HEAD" || status == web.StatusNotModified:
t.responseBody, _ = newNullResponseBody(t.conn, b.Bytes())
case t.chunkedResponse:
t.responseBody, _ = newChunkedResponseBody(t.conn, b.Bytes(), bufferSize)
default:
t.responseBody, _ = newIdentityResponseBody(t.conn, b.Bytes(), bufferSize, contentLength)
}
return t.responseBody
}
func (t *transaction) prepare() (err error) {
method, requestURI, version, err := readRequestLine(t.br)
if err != nil {
return err
}
header := web.Header{}
err = header.ParseHttpHeader(t.br)
if err != nil {
return err
}
u, err := url.ParseRequestURI(requestURI)
if err != nil {
return err
}
if u.Host == "" {
u.Host = header.Get(web.HeaderHost)
if u.Host == "" {
u.Host = t.server.DefaultHost
}
}
if t.server.Secure {
u.Scheme = "https"
} else {
u.Scheme = "http"
}
req, err := web.NewRequest(t.conn.RemoteAddr().String(), method, requestURI, version, u, header)
if err != nil {
return
}
t.req = req
if s := req.Header.Get(web.HeaderExpect); s != "" {
t.write100Continue = strings.ToLower(s) == "100-continue"
}
connection := strings.ToLower(req.Header.Get(web.HeaderConnection))
if version >= web.ProtocolVersion(1, 1) {
t.closeAfterResponse = connection == "close"
} else if version == web.ProtocolVersion(1, 0) && req.ContentLength >= 0 {
t.closeAfterResponse = connection != "keep-alive"
} else {
t.closeAfterResponse = true
}
req.Responder = t
te := header.GetList(web.HeaderTransferEncoding)
chunked := len(te) > 0 && te[0] == "chunked"
switch {
case req.Method == "GET" || req.Method == "HEAD":
req.Body = identityReader{t}
t.requestConsumed = true
case chunked:
req.Body = chunkedReader{t}
case req.ContentLength >= 0:
req.Body = identityReader{t}
t.requestAvail = req.ContentLength
t.requestConsumed = req.ContentLength == 0
default:
req.Body = identityReader{t}
t.closeAfterResponse = true
}
return nil
}