Sendgrid error 400 Bad Request - php

Question

I'm getting this error message when trying to send a email through SendGrid:
400 { "errors": [ { "message": "Bad Request", "field": null, "help": null } ] } array(14) { [0]=> string(25) "HTTP/1.1 400 Bad Request " [1]=> string(14) "Server: nginx " [2]=> string(36) "Date: Sat, 11 Mar 2017 19:20:44 GMT " [3]=> string(31) "Content-Type: application/json " [4]=> string(19) "Content-Length: 63 " [5]=> string(23) "Connection: keep-alive " [6]=> string(22) "X-Frame-Options: DENY " [7]=> string(58) "Access-Control-Allow-Origin: https://sendgrid.api-docs.io " [8]=> string(35) "Access-Control-Allow-Methods: POST " [9]=> string(87) "Access-Control-Allow-Headers: Authorization, Content-Type, On-behalf-of, x-sg-elas-acl " [10]=> string(28) "Access-Control-Max-Age: 600 " [11]=> string(75) "X-No-CORS-Reason: https://sendgrid.com/docs/Classroom/Basics/API/cors.html " [12]=> string(1) " " [13]=> string(0) "" }
Here is my code:
<?php
// If you are using Composer
require 'vendor/autoload.php';
use SendGrid\Mail;
$apiKey = 'mykey';
$sg = new \SendGrid($apiKey);
$email = new SendGrid\Email("Me", "mail#gmail.com");
$mail = new SendGrid\Mail();
$mail->setFrom($email);
$mail->setSubject("Attachment Test");
$p = new \SendGrid\Personalization();
$p->addTo($email);
$c = new \SendGrid\Content("text/plain", "Hi");
$mail->addPersonalization($p);
$mail->addContent($c);
$att1 = new \SendGrid\Attachment();
$att1->setContent( file_get_contents("favicon.ico") );
$att1->setType("text/plain");
$att1->setFilename("1.txt");
$att1->setDisposition("attachment");
$mail->addAttachment( $att1 );
$response = $sg->client->mail()->send()->post($mail);
echo $response->statusCode() . "\n";
echo json_encode( json_decode($response->body()), JSON_PRETTY_PRINT) . "\n";
var_dump($response->headers());
?>
Not sure if it's related to the attachment. I managed to send an email using a different code, but I'm trying to implement attachments to it so this is the new code. I don't know much php so I'm kinda lost on what does this error means.

Answer 1

The error that you're getting is due to the attachment.
The contents of the file must be base64 encoded. Otherwise it will malform the JSON since you're introducing random bytes into the request body.
You can see that in the complete example of the mail helper for sendgrid-php, a base64 string is set as content to the attachment.
https://github.com/sendgrid/sendgrid-php/blob/master/examples/helpers/mail/example.php#L83
As you can see in the Attachment class, the content is simply just set and will serialize as a string in the JSON object when the class is serialized:
https://github.com/sendgrid/sendgrid-php/blob/master/lib/helpers/mail/Mail.php#L670
You just need to use this function: http://php.net/manual/en/function.base64-encode.php
To change the line:
$att1->setContent( file_get_contents("favicon.ico") );
To:
$att1->setContent( base64_encode( file_get_contents("favicon.ico") ) );
The v3 Mail Send documentation is here: https://sendgrid.com/docs/API_Reference/Web_API_v3/Mail/index.html
If you scroll down to the "attachments" object and expand the "content" field, it'll show the requirements for it, maily: The Base64 encoded content of the attachment.