php - Telegram Bot API : how to send a photo using PHP?

Question

sendPhoto命令需要定义为 InputFile 或 String 的参数 photo。

API 文档告诉我们:

Photo to send. You can either pass a file_id as String to resend a photo
that is already on the Telegram servers, or upload a new photo using
multipart/form-data.

和

InputFile

This object represents the contents of a file to be uploaded. Must be
posted using multipart/form-data in the usual way that files are 
uploaded via the browser. 

于是我尝试了这个方法

    $bot_url    = "https://api.telegram.org/bot<bot_id>/";
    $url = $bot_url . "sendPhoto?chat_id=" . $chat_id;
    $ch = curl_init(); 
    curl_setopt($ch, CURLOPT_HTTPHEADER, array(
        "Content-Type:multipart/form-data"
    ));
    curl_setopt($ch, CURLOPT_URL, $url); 
    curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1); 
    curl_setopt($ch, CURLOPT_POSTFIELDS, array(
        "photo"     => "@/path/to/image.png", 
    )); 
    curl_setopt($ch, CURLOPT_INFILESIZE, filesize("/root/dev/fe_new.png"));
    $output = curl_exec($ch);

卷发已执行，但 Telegram 回复我:

Error: Bad Request: Wrong persistent file_id specified: contains wrong
characters or have wrong length

我还尝试用 file_get_contents 替换 @/path...，但在这种情况下，Telegram 给我一个空回复(和 curl_error 是空的!)。

使用 php + curl 将照片发送到 Telegram 的方法是什么？

Answer 1

这是我的工作解决方案，但它需要 PHP 5.5:

$bot_url    = "https://api.telegram.org/bot<bot_id>/";
$url        = $bot_url . "sendPhoto?chat_id=" . $chat_id ;

$post_fields = array('chat_id'   => $chat_id,
    'photo'     => new CURLFile(realpath("/path/to/image.png"))
);

$ch = curl_init(); 
curl_setopt($ch, CURLOPT_HTTPHEADER, array(
    "Content-Type:multipart/form-data"
));
curl_setopt($ch, CURLOPT_URL, $url); 
curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1); 
curl_setopt($ch, CURLOPT_POSTFIELDS, $post_fields); 
$output = curl_exec($ch);