package api import ( "fmt" "io" "mime/multipart" "net/http" "net/textproto" "strconv" "strings" "github.com/diamondburned/arikawa/discord" "github.com/diamondburned/arikawa/json" "github.com/pkg/errors" ) type SendMessageData struct { Content string `json:"content"` Nonce string `json:"nonce"` TTS bool `json:"tts"` Embed *discord.Embed `json:"embed"` Files []SendMessageFile `json:"-"` } type SendMessageFile struct { Name string ContentType string // auto-detect if empty Reader io.Reader } var quoteEscaper = strings.NewReplacer(`\`, `\\`, `"`, `\"`) func (data *SendMessageData) WriteMultipart(c json.Driver, w io.Writer) error { body := multipart.NewWriter(w) // Encode the JSON body first h := textproto.MIMEHeader{} h.Set("Content-Disposition", `form-data; name="payload_json"`) h.Set("Content-Type", "application/json") w, err := body.CreatePart(h) if err != nil { return errors.Wrap(err, "Failed to create bodypart for JSON") } if err := c.EncodeStream(w, data); err != nil { return errors.Wrap(err, "Failed to encode JSON") } // Content-Type buffer var buf []byte for i, file := range data.Files { h := textproto.MIMEHeader{} h.Set("Content-Disposition", fmt.Sprintf( `form-data; name="file%d"; filename="%s"`, i, quoteEscaper.Replace(file.Name), )) w, err := body.CreatePart(h) if err != nil { return errors.Wrap(err, "Failed to create bodypart for "+ strconv.Itoa(i)) } if file.ContentType == "" { if buf == nil { buf = make([]byte, 512) } n, err := file.Reader.Read(buf) if err != nil { return errors.Wrap(err, "Failed to read first 512 bytes for "+ strconv.Itoa(i)) } file.ContentType = http.DetectContentType(buf[:n]) data.Files[i] = file h.Set("Content-Type", file.ContentType) // Prematurely write if _, err := w.Write(buf[:n]); err != nil { return errors.Wrap(err, "Failed to write buffer for "+ strconv.Itoa(i)) } } else { h.Set("Content-Type", file.ContentType) } if _, err := io.Copy(w, file.Reader); err != nil { return errors.Wrap(err, "Failed to write file for "+ strconv.Itoa(i)) } } if err := body.Close(); err != nil { return errors.Wrap(err, "Failed to close body writer") } return nil }