http: add MultipartForm, FormFile, and ParseMultipartForm to Request
R=rsc, bradfitz
CC=golang-dev
https://golang.org/cl/4431068
diff --git a/src/pkg/http/request.go b/src/pkg/http/request.go
index 14a505d..b8e9a21 100644
--- a/src/pkg/http/request.go
+++ b/src/pkg/http/request.go
@@ -24,12 +24,17 @@
)
const (
- maxLineLength = 4096 // assumed <= bufio.defaultBufSize
- maxValueLength = 4096
- maxHeaderLines = 1024
- chunkSize = 4 << 10 // 4 KB chunks
+ maxLineLength = 4096 // assumed <= bufio.defaultBufSize
+ maxValueLength = 4096
+ maxHeaderLines = 1024
+ chunkSize = 4 << 10 // 4 KB chunks
+ defaultMaxMemory = 32 << 20 // 32 MB
)
+// ErrMissingFile is returned by FormFile when the provided file field name
+// is either not present in the request or not a file field.
+var ErrMissingFile = os.ErrorString("http: no such file")
+
// HTTP request parsing errors.
type ProtocolError struct {
os.ErrorString
@@ -136,6 +141,10 @@
// The parsed form. Only available after ParseForm is called.
Form map[string][]string
+ // The parsed multipart form, including file uploads.
+ // Only available after ParseMultipartForm is called.
+ MultipartForm *multipart.Form
+
// Trailer maps trailer keys to values. Like for Header, if the
// response has multiple trailer lines with the same key, they will be
// concatenated, delimited by commas.
@@ -165,9 +174,30 @@
r.ProtoMajor == major && r.ProtoMinor >= minor
}
+// multipartByReader is a sentinel value.
+// Its presence in Request.MultipartForm indicates that parsing of the request
+// body has been handed off to a MultipartReader instead of ParseMultipartFrom.
+var multipartByReader = &multipart.Form{
+ Value: make(map[string][]string),
+ File: make(map[string][]*multipart.FileHeader),
+}
+
// MultipartReader returns a MIME multipart reader if this is a
// multipart/form-data POST request, else returns nil and an error.
+// Use this function instead of ParseMultipartForm to
+// process the request body as a stream.
func (r *Request) MultipartReader() (multipart.Reader, os.Error) {
+ if r.MultipartForm == multipartByReader {
+ return nil, os.NewError("http: MultipartReader called twice")
+ }
+ if r.MultipartForm != nil {
+ return nil, os.NewError("http: multipart handled by ParseMultipartForm")
+ }
+ r.MultipartForm = multipartByReader
+ return r.multipartReader()
+}
+
+func (r *Request) multipartReader() (multipart.Reader, os.Error) {
v := r.Header.Get("Content-Type")
if v == "" {
return nil, ErrNotMultipart
@@ -578,7 +608,9 @@
return err
}
-// ParseForm parses the request body as a form for POST requests, or the raw query for GET requests.
+// ParseForm parses the raw query.
+// For POST requests, it also parses the request body as a form.
+// ParseMultipartForm calls ParseForm automatically.
// It is idempotent.
func (r *Request) ParseForm() (err os.Error) {
if r.Form != nil {
@@ -611,7 +643,8 @@
if err == nil {
err = e
}
- // TODO(dsymonds): Handle multipart/form-data
+ case "multipart/form-data":
+ // handled by ParseMultipartForm
default:
return &badStringError{"unknown Content-Type", ct}
}
@@ -619,11 +652,50 @@
return err
}
+// ParseMultipartForm parses a request body as multipart/form-data.
+// The whole request body is parsed and up to a total of maxMemory bytes of
+// its file parts are stored in memory, with the remainder stored on
+// disk in temporary files.
+// ParseMultipartForm calls ParseForm if necessary.
+// After one call to ParseMultipartForm, subsequent calls have no effect.
+func (r *Request) ParseMultipartForm(maxMemory int64) os.Error {
+ if r.Form == nil {
+ err := r.ParseForm()
+ if err != nil {
+ return err
+ }
+ }
+ if r.MultipartForm != nil {
+ return nil
+ }
+ if r.MultipartForm == multipartByReader {
+ return os.NewError("http: multipart handled by MultipartReader")
+ }
+
+ mr, err := r.multipartReader()
+ if err == ErrNotMultipart {
+ return nil
+ } else if err != nil {
+ return err
+ }
+
+ f, err := mr.ReadForm(maxMemory)
+ if err != nil {
+ return err
+ }
+ for k, v := range f.Value {
+ r.Form[k] = append(r.Form[k], v...)
+ }
+ r.MultipartForm = f
+
+ return nil
+}
+
// FormValue returns the first value for the named component of the query.
-// FormValue calls ParseForm if necessary.
+// FormValue calls ParseMultipartForm and ParseForm if necessary.
func (r *Request) FormValue(key string) string {
if r.Form == nil {
- r.ParseForm()
+ r.ParseMultipartForm(defaultMaxMemory)
}
if vs := r.Form[key]; len(vs) > 0 {
return vs[0]
@@ -631,6 +703,25 @@
return ""
}
+// FormFile returns the first file for the provided form key.
+// FormFile calls ParseMultipartForm and ParseForm if necessary.
+func (r *Request) FormFile(key string) (multipart.File, *multipart.FileHeader, os.Error) {
+ if r.MultipartForm == multipartByReader {
+ return nil, nil, os.NewError("http: multipart handled by MultipartReader")
+ }
+ if r.MultipartForm == nil {
+ err := r.ParseMultipartForm(defaultMaxMemory)
+ if err != nil {
+ return nil, nil, err
+ }
+ }
+ if fhs := r.MultipartForm.File[key]; len(fhs) > 0 {
+ f, err := fhs[0].Open()
+ return f, fhs[0], err
+ }
+ return nil, nil, ErrMissingFile
+}
+
func (r *Request) expectsContinue() bool {
return strings.ToLower(r.Header.Get("Expect")) == "100-continue"
}
diff --git a/src/pkg/http/request_test.go b/src/pkg/http/request_test.go
index 19083ad..f982471 100644
--- a/src/pkg/http/request_test.go
+++ b/src/pkg/http/request_test.go
@@ -10,6 +10,8 @@
. "http"
"http/httptest"
"io"
+ "io/ioutil"
+ "mime/multipart"
"os"
"reflect"
"regexp"
@@ -82,7 +84,7 @@
req.Header = Header{
"Content-Type": {"application/x-www-form-urlencoded; boo!"},
}
- req.Body = nopCloser{strings.NewReader("z=post&both=y")}
+ req.Body = ioutil.NopCloser(strings.NewReader("z=post&both=y"))
if q := req.FormValue("q"); q != "foo" {
t.Errorf(`req.FormValue("q") = %q, want "foo"`, q)
}
@@ -115,7 +117,7 @@
req := &Request{
Method: "POST",
Header: Header(test.contentType),
- Body: nopCloser{bytes.NewBufferString("body")},
+ Body: ioutil.NopCloser(bytes.NewBufferString("body")),
}
err := req.ParseForm()
if !test.error && err != nil {
@@ -131,7 +133,7 @@
req := &Request{
Method: "POST",
Header: Header{"Content-Type": {`multipart/form-data; boundary="foo123"`}},
- Body: nopCloser{new(bytes.Buffer)},
+ Body: ioutil.NopCloser(new(bytes.Buffer)),
}
multipart, err := req.MultipartReader()
if multipart == nil {
@@ -170,9 +172,115 @@
}
}
-// TODO: stop copy/pasting this around. move to io/ioutil?
-type nopCloser struct {
- io.Reader
+func TestMultipartRequest(t *testing.T) {
+ // Test that we can read the values and files of a
+ // multipart request with FormValue and FormFile,
+ // and that ParseMultipartForm can be called multiple times.
+ req := newTestMultipartRequest(t)
+ if err := req.ParseMultipartForm(25); err != nil {
+ t.Fatal("ParseMultipartForm first call:", err)
+ }
+ defer req.MultipartForm.RemoveAll()
+ validateTestMultipartContents(t, req, false)
+ if err := req.ParseMultipartForm(25); err != nil {
+ t.Fatal("ParseMultipartForm second call:", err)
+ }
+ validateTestMultipartContents(t, req, false)
}
-func (nopCloser) Close() os.Error { return nil }
+func TestMultipartRequestAuto(t *testing.T) {
+ // Test that FormValue and FormFile automatically invoke
+ // ParseMultipartForm and return the right values.
+ req := newTestMultipartRequest(t)
+ defer func() {
+ if req.MultipartForm != nil {
+ req.MultipartForm.RemoveAll()
+ }
+ }()
+ validateTestMultipartContents(t, req, true)
+}
+
+func newTestMultipartRequest(t *testing.T) *Request {
+ b := bytes.NewBufferString(strings.Replace(message, "\n", "\r\n", -1))
+ req, err := NewRequest("POST", "/", b)
+ if err != nil {
+ t.Fatalf("NewRequest:", err)
+ }
+ ctype := fmt.Sprintf(`multipart/form-data; boundary="%s"`, boundary)
+ req.Header.Set("Content-type", ctype)
+ return req
+}
+
+func validateTestMultipartContents(t *testing.T, req *Request, allMem bool) {
+ if g, e := req.FormValue("texta"), textaValue; g != e {
+ t.Errorf("texta value = %q, want %q", g, e)
+ }
+ if g, e := req.FormValue("texta"), textaValue; g != e {
+ t.Errorf("texta value = %q, want %q", g, e)
+ }
+
+ assertMem := func(n string, fd multipart.File) {
+ if _, ok := fd.(*os.File); ok {
+ t.Error(n, " is *os.File, should not be")
+ }
+ }
+ fd := testMultipartFile(t, req, "filea", "filea.txt", fileaContents)
+ assertMem("filea", fd)
+ fd = testMultipartFile(t, req, "fileb", "fileb.txt", filebContents)
+ if allMem {
+ assertMem("fileb", fd)
+ } else {
+ if _, ok := fd.(*os.File); !ok {
+ t.Errorf("fileb has unexpected underlying type %T", fd)
+ }
+ }
+}
+
+func testMultipartFile(t *testing.T, req *Request, key, expectFilename, expectContent string) multipart.File {
+ f, fh, err := req.FormFile(key)
+ if err != nil {
+ t.Fatalf("FormFile(%q):", key, err)
+ }
+ if fh.Filename != expectFilename {
+ t.Errorf("filename = %q, want %q", fh.Filename, expectFilename)
+ }
+ var b bytes.Buffer
+ _, err = io.Copy(&b, f)
+ if err != nil {
+ t.Fatal("copying contents:", err)
+ }
+ if g := b.String(); g != expectContent {
+ t.Errorf("contents = %q, want %q", g, expectContent)
+ }
+ return f
+}
+
+const (
+ fileaContents = "This is a test file."
+ filebContents = "Another test file."
+ textaValue = "foo"
+ textbValue = "bar"
+ boundary = `MyBoundary`
+)
+
+const message = `
+--MyBoundary
+Content-Disposition: form-data; name="filea"; filename="filea.txt"
+Content-Type: text/plain
+
+` + fileaContents + `
+--MyBoundary
+Content-Disposition: form-data; name="fileb"; filename="fileb.txt"
+Content-Type: text/plain
+
+` + filebContents + `
+--MyBoundary
+Content-Disposition: form-data; name="texta"
+
+` + textaValue + `
+--MyBoundary
+Content-Disposition: form-data; name="textb"
+
+` + textbValue + `
+--MyBoundary--
+`
diff --git a/src/pkg/http/server.go b/src/pkg/http/server.go
index db8b23c..96d2cb6 100644
--- a/src/pkg/http/server.go
+++ b/src/pkg/http/server.go
@@ -423,6 +423,9 @@
}
w.conn.buf.Flush()
w.req.Body.Close()
+ if w.req.MultipartForm != nil {
+ w.req.MultipartForm.RemoveAll()
+ }
if w.contentLength != -1 && w.contentLength != w.written {
// Did not write enough. Avoid getting out of sync.
