forked from valyala/fasthttp
/
http.go
834 lines (733 loc) · 19.5 KB
/
http.go
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package fasthttp
import (
"bufio"
"bytes"
"errors"
"fmt"
"io"
"mime/multipart"
"os"
"sync"
)
// Request represents HTTP request.
//
// It is forbidden copying Request instances. Create new instances
// and use CopyTo() instead.
//
// It is unsafe modifying/reading Request instance from concurrently
// running goroutines.
type Request struct {
// Request header
//
// Copying Header by value is forbidden. Use pointer to Header instead.
Header RequestHeader
body []byte
w requestBodyWriter
uri URI
parsedURI bool
postArgs Args
parsedPostArgs bool
multipartForm *multipart.Form
}
// Response represents HTTP response.
//
// It is forbidden copying Response instances. Create new instances
// and use CopyTo() instead.
//
// It is unsafe modifying/reading Response instance from concurrently
// running goroutines.
type Response struct {
// Response header
//
// Copying Header by value is forbidden. Use pointer to Header instead.
Header ResponseHeader
// Response.Read() skips reading body if set to true.
// Use it for HEAD requests.
SkipBody bool
body []byte
w responseBodyWriter
bodyStream io.Reader
}
// SetRequestURI sets RequestURI.
func (req *Request) SetRequestURI(requestURI string) {
req.Header.SetRequestURI(requestURI)
}
// SetRequestURIBytes sets RequestURI.
func (req *Request) SetRequestURIBytes(requestURI []byte) {
req.Header.SetRequestURIBytes(requestURI)
}
// StatusCode returns response status code.
func (resp *Response) StatusCode() int {
return resp.Header.StatusCode()
}
// SetStatusCode sets response status code.
func (resp *Response) SetStatusCode(statusCode int) {
resp.Header.SetStatusCode(statusCode)
}
// ConnectionClose returns true if 'Connection: close' header is set.
func (resp *Response) ConnectionClose() bool {
return resp.Header.ConnectionClose()
}
// SetConnectionClose sets 'Connection: close' header.
func (resp *Response) SetConnectionClose() {
resp.Header.SetConnectionClose()
}
// ConnectionClose returns true if 'Connection: close' header is set.
func (req *Request) ConnectionClose() bool {
return req.Header.ConnectionClose()
}
// SetConnectionClose sets 'Connection: close' header.
func (req *Request) SetConnectionClose() {
req.Header.SetConnectionClose()
}
// SendFile registers file on the given path to be used as response body
// when Write is called.
//
// Note that SendFile doesn't set Content-Type, so set it yourself
// with Header.SetContentType.
func (resp *Response) SendFile(path string) error {
f, err := os.Open(path)
if err != nil {
return err
}
fileInfo, err := f.Stat()
if err != nil {
f.Close()
return err
}
size64 := fileInfo.Size()
size := int(size64)
if int64(size) != size64 {
size = -1
}
resp.Header.SetLastModified(fileInfo.ModTime())
resp.SetBodyStream(f, size)
return nil
}
// SetBodyStream sets response body stream and, optionally body size.
//
// If bodySize is >= 0, then the bodyStream must provide exactly bodySize bytes
// before returning io.EOF.
//
// If bodySize < 0, then bodyStream is read until io.EOF.
//
// bodyStream.Close() is called after finishing reading all body data
// if it implements io.Closer.
//
// See also SetBodyStreamWriter.
func (resp *Response) SetBodyStream(bodyStream io.Reader, bodySize int) {
resp.body = resp.body[:0]
resp.closeBodyStream()
resp.bodyStream = bodyStream
resp.Header.SetContentLength(bodySize)
}
// SetBodyStreamWriter registers the given sw for populating response body.
//
// This function may be used in the following cases:
//
// * if response body is too big (more than 10MB).
// * if response body is streamed from slow external sources.
// * if response body must be streamed to the client in chunks
// (aka `http server push`).
func (resp *Response) SetBodyStreamWriter(sw StreamWriter) {
sr := NewStreamReader(sw)
resp.SetBodyStream(sr, -1)
}
// BodyWriter returns writer for populating response body.
//
// If used inside RequestHandler, the returned writer must not be used
// after returning from RequestHandler. Use RequestCtx.Write
// or SetBodyStreamWriter in this case.
func (resp *Response) BodyWriter() io.Writer {
resp.w.r = resp
return &resp.w
}
// BodyWriter returns writer for populating request body.
func (req *Request) BodyWriter() io.Writer {
req.w.r = req
return &req.w
}
type responseBodyWriter struct {
r *Response
}
func (w *responseBodyWriter) Write(p []byte) (int, error) {
w.r.AppendBody(p)
return len(p), nil
}
type requestBodyWriter struct {
r *Request
}
func (w *requestBodyWriter) Write(p []byte) (int, error) {
w.r.AppendBody(p)
return len(p), nil
}
// Body returns response body.
func (resp *Response) Body() []byte {
return resp.body
}
// AppendBody appends p to response body.
func (resp *Response) AppendBody(p []byte) {
resp.closeBodyStream()
resp.body = append(resp.body, p...)
}
// SetBody sets response body.
func (resp *Response) SetBody(body []byte) {
resp.closeBodyStream()
resp.body = append(resp.body[:0], body...)
}
// SetBodyString sets response body.
func (resp *Response) SetBodyString(body string) {
resp.closeBodyStream()
resp.body = AppendBytesStr(resp.body[:0], body)
}
// ResetBody resets response body.
func (resp *Response) ResetBody() {
resp.closeBodyStream()
resp.body = resp.body[:0]
}
// Body returns request body.
func (req *Request) Body() []byte {
return req.body
}
// AppendBody appends p to request body.
func (req *Request) AppendBody(p []byte) {
req.body = append(req.body, p...)
}
// SetBody sets request body.
func (req *Request) SetBody(body []byte) {
req.body = append(req.body[:0], body...)
}
// SetBodyString sets request body.
func (req *Request) SetBodyString(body string) {
req.body = AppendBytesStr(req.body[:0], body)
}
// ResetBody resets request body.
func (req *Request) ResetBody() {
req.body = req.body[:0]
}
// CopyTo copies req contents to dst.
func (req *Request) CopyTo(dst *Request) {
dst.Reset()
req.Header.CopyTo(&dst.Header)
dst.body = append(dst.body[:0], req.body...)
req.uri.CopyTo(&dst.uri)
dst.parsedURI = req.parsedURI
req.postArgs.CopyTo(&dst.postArgs)
dst.parsedPostArgs = req.parsedPostArgs
// do not copy multipartForm - it will be automatically
// re-created on the first call to MultipartForm.
}
// CopyTo copies resp contents to dst except of body stream.
func (resp *Response) CopyTo(dst *Response) {
dst.Reset()
resp.Header.CopyTo(&dst.Header)
dst.body = append(dst.body[:0], resp.body...)
dst.SkipBody = resp.SkipBody
}
// URI returns request URI
func (req *Request) URI() *URI {
req.parseURI()
return &req.uri
}
func (req *Request) parseURI() {
if req.parsedURI {
return
}
req.parsedURI = true
req.uri.parseQuick(req.Header.RequestURI(), &req.Header)
}
// PostArgs returns POST arguments.
func (req *Request) PostArgs() *Args {
req.parsePostArgs()
return &req.postArgs
}
func (req *Request) parsePostArgs() {
if req.parsedPostArgs {
return
}
req.parsedPostArgs = true
if !req.Header.IsPost() {
return
}
if !bytes.Equal(req.Header.ContentType(), strPostArgsContentType) {
return
}
req.postArgs.ParseBytes(req.body)
return
}
// ErrNoMultipartForm means that the request's Content-Type
// isn't 'multipart/form-data'.
var ErrNoMultipartForm = errors.New("request has no multipart/form-data Content-Type")
// MultipartForm returns requests's multipart form.
//
// Returns ErrNoMultipartForm if request's content-type
// isn't 'multipart/form-data'.
func (req *Request) MultipartForm() (*multipart.Form, error) {
if req.multipartForm != nil {
return req.multipartForm, nil
}
boundary := req.Header.MultipartFormBoundary()
if len(boundary) == 0 {
return nil, ErrNoMultipartForm
}
f, err := readMultipartFormBody(bytes.NewReader(req.body), boundary, 0, len(req.body))
if err != nil {
return nil, err
}
req.multipartForm = f
return f, nil
}
func readMultipartFormBody(r io.Reader, boundary []byte, maxBodySize, maxInMemoryFileSize int) (*multipart.Form, error) {
// Do not care about memory allocations here, since they are tiny
// compared to multipart data (aka multi-MB files) usually sent
// in multipart/form-data requests.
if maxBodySize > 0 {
r = io.LimitReader(r, int64(maxBodySize))
}
mr := multipart.NewReader(r, string(boundary))
f, err := mr.ReadForm(int64(maxInMemoryFileSize))
if err != nil {
return nil, fmt.Errorf("cannot read multipart/form-data body: %s", err)
}
return f, nil
}
// Reset clears request contents.
func (req *Request) Reset() {
req.Header.Reset()
req.resetSkipHeader()
}
func (req *Request) resetSkipHeader() {
req.body = req.body[:0]
req.uri.Reset()
req.parsedURI = false
req.postArgs.Reset()
req.parsedPostArgs = false
req.RemoveMultipartFormFiles()
}
// RemoveMultipartFormFiles removes multipart/form-data temporary files
// associated with the request.
func (req *Request) RemoveMultipartFormFiles() {
if req.multipartForm != nil {
// Do not check for error, since these files may be deleted or moved
// to new places by user code.
req.multipartForm.RemoveAll()
req.multipartForm = nil
}
}
// Reset clears response contents.
func (resp *Response) Reset() {
resp.Header.Reset()
resp.resetSkipHeader()
resp.SkipBody = false
}
func (resp *Response) resetSkipHeader() {
resp.closeBodyStream()
resp.body = resp.body[:0]
}
// Read reads request (including body) from the given r.
//
// RemoveMultipartFormFiles or Reset must be called after
// reading multipart/form-data request in order to delete temporarily
// uploaded files.
func (req *Request) Read(r *bufio.Reader) error {
return req.ReadLimitBody(r, 0)
}
const defaultMaxInMemoryFileSize = 16 * 1024 * 1024
var errGetOnly = errors.New("non-GET request received")
// ReadLimitBody reads request from the given r, limiting the body size.
//
// If maxBodySize > 0 and the body size exceeds maxBodySize,
// then ErrBodyTooLarge is returned.
//
// RemoveMultipartFormFiles or Reset must be called after
// reading multipart/form-data request in order to delete temporarily
// uploaded files.
func (req *Request) ReadLimitBody(r *bufio.Reader, maxBodySize int) error {
return req.readLimitBody(r, maxBodySize, false)
}
func (req *Request) readLimitBody(r *bufio.Reader, maxBodySize int, getOnly bool) error {
req.resetSkipHeader()
err := req.Header.Read(r)
if err != nil {
return err
}
if getOnly && !req.Header.IsGet() {
return errGetOnly
}
if !req.Header.noBody() {
contentLength := req.Header.ContentLength()
if contentLength > 0 {
// Pre-read multipart form data of known length.
// This way we limit memory usage for large file uploads, since their contents
// is streamed into temporary files if file size exceeds defaultMaxInMemoryFileSize.
boundary := req.Header.MultipartFormBoundary()
if len(boundary) > 0 {
req.multipartForm, err = readMultipartFormBody(r, boundary, maxBodySize, defaultMaxInMemoryFileSize)
if err != nil {
req.Reset()
}
return err
}
}
req.body, err = readBody(r, contentLength, maxBodySize, req.body)
if err != nil {
req.Reset()
return err
}
req.Header.SetContentLength(len(req.body))
}
return nil
}
// Read reads response (including body) from the given r.
func (resp *Response) Read(r *bufio.Reader) error {
return resp.ReadLimitBody(r, 0)
}
// ReadLimitBody reads response from the given r, limiting the body size.
//
// If maxBodySize > 0 and the body size exceeds maxBodySize,
// then ErrBodyTooLarge is returned.
func (resp *Response) ReadLimitBody(r *bufio.Reader, maxBodySize int) error {
resp.resetSkipHeader()
err := resp.Header.Read(r)
if err != nil {
return err
}
if !isSkipResponseBody(resp.Header.StatusCode()) && !resp.SkipBody {
resp.body, err = readBody(r, resp.Header.ContentLength(), maxBodySize, resp.body)
if err != nil {
resp.Reset()
return err
}
resp.Header.SetContentLength(len(resp.body))
}
return nil
}
func isSkipResponseBody(statusCode int) bool {
// From http/1.1 specs:
// All 1xx (informational), 204 (no content), and 304 (not modified) responses MUST NOT include a message-body
if statusCode >= 100 && statusCode < 200 {
return true
}
return statusCode == StatusNoContent || statusCode == StatusNotModified
}
var errRequestHostRequired = errors.New("Missing required Host header in request")
// Write writes request to w.
//
// Write doesn't flush request to w for performance reasons.
func (req *Request) Write(w *bufio.Writer) error {
if len(req.Header.Host()) == 0 {
uri := req.URI()
host := uri.Host()
if len(host) == 0 {
return errRequestHostRequired
}
req.Header.SetHostBytes(host)
req.Header.SetRequestURIBytes(uri.RequestURI())
}
req.Header.SetContentLength(len(req.body))
err := req.Header.Write(w)
if err != nil {
return err
}
if !req.Header.noBody() {
_, err = w.Write(req.body)
} else if len(req.body) > 0 {
return fmt.Errorf("Non-zero body for non-POST request. body=%q", req.body)
}
return err
}
// Write writes response to w.
//
// Write doesn't flush response to w for performance reasons.
func (resp *Response) Write(w *bufio.Writer) error {
var err error
if resp.bodyStream != nil {
contentLength := resp.Header.ContentLength()
if contentLength < 0 {
lrSize := limitedReaderSize(resp.bodyStream)
if lrSize >= 0 {
contentLength = int(lrSize)
if int64(contentLength) != lrSize {
contentLength = -1
}
}
}
if contentLength >= 0 {
resp.Header.SetContentLength(contentLength)
if err = resp.Header.Write(w); err != nil {
return err
}
if err = writeBodyFixedSize(w, resp.bodyStream, int64(contentLength)); err != nil {
return err
}
} else {
resp.Header.SetContentLength(-1)
if err = resp.Header.Write(w); err != nil {
return err
}
if err = writeBodyChunked(w, resp.bodyStream); err != nil {
return err
}
}
return resp.closeBodyStream()
}
resp.Header.SetContentLength(len(resp.body))
if err = resp.Header.Write(w); err != nil {
return err
}
_, err = w.Write(resp.body)
return err
}
func (resp *Response) closeBodyStream() error {
if resp.bodyStream == nil {
return nil
}
var err error
if bsc, ok := resp.bodyStream.(io.Closer); ok {
err = bsc.Close()
}
resp.bodyStream = nil
return err
}
// String returns request representation.
//
// Returns error message instead of request representation on error.
//
// Use Write instead of String for performance-critical code.
func (req *Request) String() string {
return getHTTPString(req)
}
// String returns response representation.
//
// Returns error message instead of response representation on error.
//
// Use Write instead of String for performance-critical code.
func (resp *Response) String() string {
return getHTTPString(resp)
}
func getHTTPString(hw httpWriter) string {
var w bytes.Buffer
bw := bufio.NewWriter(&w)
if err := hw.Write(bw); err != nil {
return err.Error()
}
if err := bw.Flush(); err != nil {
return err.Error()
}
return string(w.Bytes())
}
type httpWriter interface {
Write(w *bufio.Writer) error
}
func writeBodyChunked(w *bufio.Writer, r io.Reader) error {
vbuf := copyBufPool.Get()
buf := vbuf.([]byte)
var err error
var n int
for {
n, err = r.Read(buf)
if n == 0 {
if err == nil {
panic("BUG: io.Reader returned 0, nil")
}
if err == io.EOF {
if err = writeChunk(w, buf[:0]); err != nil {
break
}
err = nil
}
break
}
if err = writeChunk(w, buf[:n]); err != nil {
break
}
}
copyBufPool.Put(vbuf)
return err
}
func limitedReaderSize(r io.Reader) int64 {
lr, ok := r.(*io.LimitedReader)
if !ok {
return -1
}
return lr.N
}
func writeBodyFixedSize(w *bufio.Writer, r io.Reader, size int64) error {
if size > maxSmallFileSize {
// w buffer must be empty for triggering
// sendfile path in bufio.Writer.ReadFrom.
if err := w.Flush(); err != nil {
return err
}
}
// Unwrap a single limited reader for triggering sendfile path
// in net.TCPConn.ReadFrom.
lr, ok := r.(*io.LimitedReader)
if ok {
r = lr.R
}
n, err := copyZeroAlloc(w, r)
if ok {
lr.N -= n
}
if n != size && err == nil {
err = fmt.Errorf("copied %d bytes from response body stream instead of %d bytes", n, size)
}
return err
}
func copyZeroAlloc(w io.Writer, r io.Reader) (int64, error) {
vbuf := copyBufPool.Get()
buf := vbuf.([]byte)
n, err := io.CopyBuffer(w, r, buf)
copyBufPool.Put(vbuf)
return n, err
}
var copyBufPool = sync.Pool{
New: func() interface{} {
return make([]byte, 4096)
},
}
func writeChunk(w *bufio.Writer, b []byte) error {
n := len(b)
writeHexInt(w, n)
w.Write(strCRLF)
w.Write(b)
_, err := w.Write(strCRLF)
return err
}
// ErrBodyTooLarge is returned if either request or response body exceeds
// the given limit.
var ErrBodyTooLarge = errors.New("body size exceeds the given limit")
func readBody(r *bufio.Reader, contentLength int, maxBodySize int, dst []byte) ([]byte, error) {
dst = dst[:0]
if contentLength >= 0 {
if maxBodySize > 0 && contentLength > maxBodySize {
return dst, ErrBodyTooLarge
}
return appendBodyFixedSize(r, dst, contentLength)
}
if contentLength == -1 {
return readBodyChunked(r, maxBodySize, dst)
}
return readBodyIdentity(r, maxBodySize, dst)
}
func readBodyIdentity(r *bufio.Reader, maxBodySize int, dst []byte) ([]byte, error) {
dst = dst[:cap(dst)]
if len(dst) == 0 {
dst = make([]byte, 1024)
}
offset := 0
for {
nn, err := r.Read(dst[offset:])
if nn <= 0 {
if err != nil {
if err == io.EOF {
return dst[:offset], nil
}
return dst[:offset], err
}
panic(fmt.Sprintf("BUG: bufio.Read() returned (%d, nil)", nn))
}
offset += nn
if maxBodySize > 0 && offset > maxBodySize {
return dst[:offset], ErrBodyTooLarge
}
if len(dst) == offset {
n := round2(2 * offset)
if maxBodySize > 0 && n > maxBodySize {
n = maxBodySize + 1
}
b := make([]byte, n)
copy(b, dst)
dst = b
}
}
}
func appendBodyFixedSize(r *bufio.Reader, dst []byte, n int) ([]byte, error) {
if n == 0 {
return dst, nil
}
offset := len(dst)
dstLen := offset + n
if cap(dst) < dstLen {
b := make([]byte, round2(dstLen))
copy(b, dst)
dst = b
}
dst = dst[:dstLen]
for {
nn, err := r.Read(dst[offset:])
if nn <= 0 {
if err != nil {
if err == io.EOF {
err = io.ErrUnexpectedEOF
}
return dst[:offset], err
}
panic(fmt.Sprintf("BUG: bufio.Read() returned (%d, nil)", nn))
}
offset += nn
if offset == dstLen {
return dst, nil
}
}
}
func readBodyChunked(r *bufio.Reader, maxBodySize int, dst []byte) ([]byte, error) {
if len(dst) > 0 {
panic("BUG: expected zero-length buffer")
}
strCRLFLen := len(strCRLF)
for {
chunkSize, err := parseChunkSize(r)
if err != nil {
return dst, err
}
if maxBodySize > 0 && len(dst)+chunkSize > maxBodySize {
return dst, ErrBodyTooLarge
}
dst, err = appendBodyFixedSize(r, dst, chunkSize+strCRLFLen)
if err != nil {
return dst, err
}
if !bytes.Equal(dst[len(dst)-strCRLFLen:], strCRLF) {
return dst, fmt.Errorf("cannot find crlf at the end of chunk")
}
dst = dst[:len(dst)-strCRLFLen]
if chunkSize == 0 {
return dst, nil
}
}
}
func parseChunkSize(r *bufio.Reader) (int, error) {
n, err := readHexInt(r)
if err != nil {
return -1, err
}
c, err := r.ReadByte()
if err != nil {
return -1, fmt.Errorf("cannot read '\r' char at the end of chunk size: %s", err)
}
if c != '\r' {
return -1, fmt.Errorf("unexpected char %q at the end of chunk size. Expected %q", c, '\r')
}
c, err = r.ReadByte()
if err != nil {
return -1, fmt.Errorf("cannot read '\n' char at the end of chunk size: %s", err)
}
if c != '\n' {
return -1, fmt.Errorf("unexpected char %q at the end of chunk size. Expected %q", c, '\n')
}
return n, nil
}
func round2(n int) int {
if n <= 0 {
return 0
}
n--
x := uint(0)
for n > 0 {
n >>= 1
x++
}
return 1 << x
}