Better SendPhoto for non-network

broker.go

@@ -61,7 +61,7 @@ func (b *Broker) SendTextMessage(chat *APIChat, text string, extra *MessageOptio
 // SendPhoto sends a photo with an optional caption to a chat.
 // A reply_to message ID can be specified as optional parameter.
 func (b *Broker) SendPhoto(chat *APIChat, data []byte, filename string, caption string, extra *MessageOptions) {
-	photodata := &ClientPhotoData{
+	photodata := &ClientPhotoDataNet{
 		ChatID:   chat.ChatID,
 		Filename: filename,
 		Bytes:    base64.StdEncoding.EncodeToString(data),

cmd/tg-broker/action.go

@@ -13,10 +13,10 @@ func executeClientCommand(action tg.ClientCommand, client net.Conn) {
 		api.SendTextMessage(data)
 	case tg.CmdGetFile:
 		data := *(action.FileRequestData)
-		api.GetFile(data, client, *action.Callback)
+		api.GetFileNet(data, client, *action.Callback)
 	case tg.CmdSendPhoto:
 		data := *(action.PhotoData)
-		api.SendPhoto(data)
+		api.SendPhotoNet(data)
 	case tg.CmdForwardMessage:
 		data := *(action.ForwardMessageData)
 		api.ForwardMessage(data)

command.go

@@ -68,6 +68,15 @@ type ClientTextMessageData struct {
 
 // ClientPhotoData is the required data for a CmdSendPhoto request
 type ClientPhotoData struct {
+	ChatID   int64
+	Bytes    []byte
+	Filename string
+	Caption  string `json:",omitempty"`
+	ReplyID  *int64 `json:",omitempty"`
+}
+
+// ClientPhotoDataNet is the required data for a CmdSendPhoto request over the wire
+type ClientPhotoDataNet struct {
 	ChatID   int64
 	Bytes    string
 	Filename string
@@ -156,7 +165,7 @@ type FileRequestData struct {
 type ClientCommand struct {
 	Type               ClientCommandType
 	TextMessageData    *ClientTextMessageData    `json:",omitempty"`
-	PhotoData          *ClientPhotoData          `json:",omitempty"`
+	PhotoData          *ClientPhotoDataNet       `json:",omitempty"`
 	ForwardMessageData *ClientForwardMessageData `json:",omitempty"`
 	ChatActionData     *ClientChatActionData     `json:",omitempty"`
 	InlineQueryResults *InlineQueryResponse      `json:",omitempty"`

telegram.go

@@ -110,16 +110,24 @@ func (t Telegram) SendTextMessage(data ClientTextMessageData) (APIMessage, error
 	return out.Result, err
 }
 
-// SendPhoto sends a picture to a chat as a photo
-func (t Telegram) SendPhoto(data ClientPhotoData) (APIMessage, error) {
-	// Decode photo from b64
-	photolen := base64.StdEncoding.DecodedLen(len(data.Bytes))
-	photobytes := make([]byte, photolen)
-	decoded, err := base64.StdEncoding.Decode(photobytes, []byte(data.Bytes))
-	if checkerr("SendPhoto/base64.Decode", err) {
+// SendPhotoNet decodes a network SendPhoto request and executes it
+func (t Telegram) SendPhotoNet(data ClientPhotoDataNet) (APIMessage, error) {
+	byt, err := base64.StdEncoding.DecodeString(data.Bytes)
+	if checkerr("SendPhotoNet/base64.Decode", err) {
 		return APIMessage{}, err
 	}
 
+	return t.SendPhoto(ClientPhotoData{
+		ChatID:   data.ChatID,
+		Bytes:    byt,
+		Filename: data.Filename,
+		Caption:  data.Caption,
+		ReplyID:  data.ReplyID,
+	})
+}
+
+// SendPhoto sends a picture to a chat as a photo
+func (t Telegram) SendPhoto(data ClientPhotoData) (APIMessage, error) {
 	// Write file into multipart buffer
 	body := new(bytes.Buffer)
 	writer := multipart.NewWriter(body)
@@ -127,7 +135,7 @@ func (t Telegram) SendPhoto(data ClientPhotoData) (APIMessage, error) {
 	if checkerr("SendPhoto/multipart.CreateFormFile", err) {
 		return APIMessage{}, err
 	}
-	part.Write(photobytes[0:decoded])
+	part.Write(data.Bytes)
 
 	// Write other fields
 	writer.WriteField("chat_id", strconv.FormatInt(data.ChatID, 10))
@@ -377,23 +385,13 @@ func (t Telegram) AnswerInlineQuery(data InlineQueryResponse) error {
 // GetFile sends a "getFile" API call to Telegram's servers and fetches the file
 // specified afterward. The file will be then send back to the client that requested it
 // with the specified callback id.
-func (t Telegram) GetFile(data FileRequestData, client net.Conn, callback int) {
-	fail := func(msg string) {
-		errmsg, _ := json.Marshal(BrokerUpdate{
-			Type:     BError,
-			Error:    &msg,
-			Callback: &callback,
-		})
-		fmt.Fprintln(client, string(errmsg))
-	}
-
+func (t Telegram) GetFile(data FileRequestData) ([]byte, error) {
 	postdata := url.Values{
 		"file_id": {data.FileID},
 	}
 	resp, err := http.PostForm(t.apiURL("getFile"), postdata)
 	if checkerr("GetFile/post", err) {
-		fail("Server didn't like my request")
-		return
+		return nil, fmt.Errorf("Server didn't like my request: %w", err)
 	}
 	defer resp.Body.Close()
 
@@ -403,27 +401,23 @@ func (t Telegram) GetFile(data FileRequestData, client net.Conn, callback int) {
 	}{}
 	err = json.NewDecoder(resp.Body).Decode(&filespecs)
 	if checkerr("GetFile/json.Decode", err) {
-		fail("Server sent garbage (or error)")
-		return
+		return nil, fmt.Errorf("Server sent garbage (or error): %w", err)
 	}
 	if filespecs.Result == nil {
-		fail("Server didn't send a file info, does the file exist?")
-		return
+		return nil, fmt.Errorf("Server didn't send a file info, does the file exist?")
 	}
 	result := *filespecs.Result
 
 	path := APIEndpoint + "file/bot" + t.Token + "/" + *result.Path
 	fileresp, err := http.Get(path)
 	if checkerr("GetFile/get", err) {
-		fail("Could not retrieve file from Telegram's servers")
-		return
+		return nil, fmt.Errorf("Could not retrieve file from Telegram's servers: %w", err)
 	}
 	defer fileresp.Body.Close()
 
 	rawdata, err := ioutil.ReadAll(fileresp.Body)
 	if checkerr("GetFile/ioutil.ReadAll", err) {
-		fail("Could not read file data")
-		return
+		return nil, fmt.Errorf("Could not read file data: %w", err)
 	}
 
 	rawlen := len(rawdata)
@@ -431,15 +425,35 @@ func (t Telegram) GetFile(data FileRequestData, client net.Conn, callback int) {
 		// ???
 		log.Printf("[GetFile] WARN ?? Downloaded file does not match provided filesize: %d != %d\n", rawlen, *result.Size)
 	}
-	b64data := base64.StdEncoding.EncodeToString(rawdata)
+	return rawdata, nil
+}
 
+func (t Telegram) GetFileNet(data FileRequestData, client net.Conn, callback int) {
+	byt, err := t.GetFile(data)
+	if err != nil {
+		errstr := err.Error()
+		errmsg, _ := json.Marshal(BrokerUpdate{
+			Type:     BError,
+			Error:    &errstr,
+			Callback: &callback,
+		})
+		fmt.Fprintln(client, string(errmsg))
+	}
+
+	b64data := base64.StdEncoding.EncodeToString(byt)
 	clientmsg, err := json.Marshal(BrokerUpdate{
 		Type:     BFile,
 		Bytes:    &b64data,
 		Callback: &callback,
 	})
 	if checkerr("GetFile/json.Marshal", err) {
-		fail("Could not serialize reply JSON")
+		errstr := "Could not serialize reply JSON"
+		errmsg, _ := json.Marshal(BrokerUpdate{
+			Type:     BError,
+			Error:    &errstr,
+			Callback: &callback,
+		})
+		fmt.Fprintln(client, string(errmsg))
 		return
 	}