src/LINEBot.php
public function uploadRichMenuImage($richMenuId, $imagePath, $contentType)
    {
        $url = sprintf('%s/v2/bot/richmenu/%s/content', $this->endpointBase, urlencode($richMenuId));
        return $this->httpClient->post(
            $url,
            [
                '__file' => $imagePath,
                '__type' => $contentType,
            ],
            [ "Content-Type: $contentType" ]
        );
    }
public function uploadRichMenuImage($richMenuId, $imagePath, $contentType)
    {
        $url = sprintf('%s/v2/bot/richmenu/%s/content', $this->endpointBase, urlencode($richMenuId));
        return $this->httpClient->post(
            $url,
            [
                '__file' => $imagePath,
                '__type' => $contentType,
            ],
            [ "Content-Type: $contentType" ]
        );
    }
public function uploadRichMenuImage ( $ richMenuId , $ imagePath , $ contentType ) { $ url = sprintf ( '%s/v2/bot/richmenu/%s/content' , $ this -> endpointBase , urlencode ( $ richMenuId ) ) ; return $ this -> httpClient -> post ( $ url , [ '__file' => $ imagePath , '__type' => $ contentType , ] , [ "Content-Type: $contentType" ] ) ; }
Uploads and attaches an image to a rich menu.

Notes:
<ul><li>Images must have one of the following resolutions: 2500x1686 or 2500x843 pixels.</li>
<li>You cannot replace an image attached to a rich menu. To update your rich menu image,
create a new rich menu object and upload another image.</li></ul>

@param string $richMenuId ID of an uploaded rich menu
@param string $imagePath Path to the image
@param string $contentType image/jpeg or image/png
@return Response
Uploads and attaches an image to a rich menu .