When uploading a file to my go app, I encounter a panic.
panic: runtime error: invalid memory address or nil pointer dereference
/Users/bob/Projects/go/src/github.com/zenazn/goji/web/middleware/recoverer.go:24 (0xbaf5b)
func.006: debug.PrintStack()
/usr/local/go/src/pkg/runtime/panic.c:248 (0x1043d)
panic: runtime·newstackcall(d->fn, (byte*)d->args, d->siz);
/usr/local/go/src/pkg/runtime/panic.c:552 (0x10eed)
panicstring: runtime·panic(err);
/usr/local/go/src/pkg/runtime/os_darwin.c:454 (0xfb8e)
sigpanic: runtime·panicstring("invalid memory address or nil pointer dereference");
/usr/local/go/src/pkg/mime/multipart/multipart.go:223 (0xb6801)
(*Reader).NextPart: if r.currentPart != nil {
/Users/bob/Projects/go/src/github.com/app/controllers/company_sheet_controller.go:32 (0x2ee18)
NewCompanySheet: part, err := mr.NextPart()
/usr/local/go/src/pkg/net/http/server.go:1235 (0x44f00)
HandlerFunc.ServeHTTP: f(w, r)
/Users/bob/Projects/go/src/github.com/zenazn/goji/web/router.go:113 (0x6bc0a)
This method handles an upload from a multipart form, extracting the file contents and boundary data. The r.FormFile
method on request is used to set file and header. And in order to pull the additional data from the post, I use r.MultipartReader
. From the error description I see r
is already declared as ParseMultipartForm
when using r.FormFile
. When executing the function with the different request methods individually, I receive no errors. r.FormFile
and r.MultipartReader
work fine isolated. Am I unable to mix the two request methods?
func Upload(r *http.Request) {
file, header, err := r.FormFile("file")
ErrorCheck(err)
mr, err := r.MultipartReader()
ErrorCheck(err)
part, err := mr.NextPart()
ErrorCheck(err)
var b bytes.Buffer
io.CopyN(&b, part, int64(1<<20))
fmt.Println(b.String())
defer file.Close()
}