Where to find body of email depending of mimeType

Question

I am making a request to the User.messages endpoint. All objects returned (the emails) have a mimeType property which I\'m struggling to understand.

More specificall

Answer 1

I know this question is not new but I've wrote a PHP script which correctly parses messages pulled from Gmail API, including any type of attachment.

The script includes a recursive "iterateParts" function which iterates all message parts so we can be sure we extracted all available data from each message.

Script steps are:

1. Pull all message ids from API
2. Get some important headers (subject & from address)
3. Either body is directly on payload or send payload to iterateParts
4. iterateParts is parsing each message to $msgArr with it's data, base64 encoded
5. Push $msgArr to master array $allmsgArr
6. Traverse master array and save each part as file according to it's MIME type and filename

    $maxToPull = 1;
    $gmailQuery = "ALL";

    // Initializing Google API
    $service = new Google_Service_Gmail($client);

    // Pulling all gmail messages into $messages array
    $user = 'me';
    $msglist = $service->users_messages->listUsersMessages($user, ["maxResults"=>$maxToPull, "q"=>$gmailQuery]);
    $messages = $msglist->getMessages();

    // Master array that will hold all parsed messages data, including attachments
    $allmsgArr = array();

    // Traverse each message
    foreach($messages as $message)
    {
        $msgArr = array();
        $single_message = $service->users_messages->get('me', $message->getId());
        $payload = $single_message->getPayload();

        // Nice to have the gmail msg id, can be used to direct access the message in Gmail's web gui
        $msgArr['gmailmsgid'] = $message->getId();

        // Retrieving the subject and "from" email address
        foreach($payload->getheaders() as $oneheader)
        {
            if($oneheader['name'] == 'Subject')
                $msgArr['subject'] = $oneheader['value'];
            if($oneheader['name'] == 'From')
                $msgArr['fromaddress'] = substr($oneheader['value'], strpos($oneheader['value'], '<')+1, -1);
        }

        // If body is directly in the message payload (only for plain text messages where there's no HTML part and no attachments, normally this is not the case)
        if($payload['body']['size'] > 0)
            $msgArr['textplain'] = $payload['body']['data'];     
        // Else, iterate over each message part and continue to dig if necessary
        else
            iterateParts($payload, $message->getId());

        // Push the parsed $msgArr (parsed by iterateParts) to master array
        array_push($allmsgArr, $msgArr);
    }


    // Traverse each parsed message and saving it's content and attachments to files
    foreach($allmsgArr as $onemsgArr)
    {

        $folder = "messages/".$onemsgArr['gmailmsgid'];
        mkdir($folder);

        if($onemsgArr['textplain'])
            file_put_contents($folder."/textplain.txt", decodeData($onemsgArr['textplain']));
        if($onemsgArr['texthtml'])
            file_put_contents($folder."/texthtml.html", decodeData($onemsgArr['texthtml']));
        if($onemsgArr['attachments'])
        {
            foreach($onemsgArr['attachments'] as $oneattachment)
            {
                if(!empty($oneattachment['filename']))
                    $filename = $oneattachment['filename'];
                else if($oneattachment['mimetype'] == "message/rfc822" && empty($oneattachment['filename'])) // email attachments
                    $filename = "noname.eml";
                else
                    $filename = "unknown";
                file_put_contents($folder."/".$filename, decodeData($oneattachment['data']));
            }
        }
    }


    function iterateParts($obj, $msgid) {

        global $msgArr;
        global $service;
        foreach($obj as $parts)
        {
            // if found body data
            if($parts['body']['size'] > 0)
            {
                // plain text representation of message body
                if($parts['mimeType'] == 'text/plain')
                {
                    $msgArr['textplain'] = $parts['body']['data'];
                }
                // html representation of message body
                else if($parts['mimeType'] == 'text/html')
                {
                    $msgArr['texthtml'] = $parts['body']['data'];
                }
                // if it's an attachment
                else if(!empty($parts['body']['attachmentId']))
                {
                    $attachArr['mimetype'] = $parts['mimeType'];
                    $attachArr['filename'] = $parts['filename'];
                    $attachArr['attachmentId'] = $parts['body']['attachmentId'];

                    // the message holds the attachment id, retrieve it's data from users_messages_attachments
                    $attachmentId_base64 = $parts['body']['attachmentId'];
                    $single_attachment = $service->users_messages_attachments->get('me', $msgid, $attachmentId_base64);

                    $attachArr['data'] = $single_attachment->getData();

                    $msgArr['attachments'][] = $attachArr;
                }       
            }

            // if there are other parts inside, go get them
            if(!empty($parts['parts']) && !empty($parts['mimeType']) && empty($parts['body']['attachmentId']))
            {
                iterateParts($parts->getParts(), $msgid);
            }

        }
    }

    // All data returned from API is base64 encoded
    function decodeData($data)
    {
        $sanitizedData = strtr($data,'-_', '+/');
        return base64_decode($sanitizedData);
    }

This is how $allmsgArr will look like (where only one message was pulled):

Array
(
    [0] => Array
        (
            [gmailmsgid] => 25k1asfa556x2da
            [fromaddress] => john@gmail.com
            [subject] => Fwd: Sea gulls picture
            [textplain] => UE5SIDQxQzAwMg0KDQpBUkJFTFRFU1QxDQoNCg0K
            [texthtml] => PGRpdiBkaXI9Imx0ciI-PHNwYW4gc3R5bGU9ImZi
            [attachments] => Array
                (
                    [0] => Array
                        (
                            [mimetype] => image/png
                            [filename] => sea_gulls.png
                            [attachmentId] => ANGjdJ9tmy4d8vPXhU_BjNEFEaDODOpu29W2u5OTM7a0
                            [data] => iVBORw0KGgoAAAANSUhEUgAABSYAAAKWCAYAAABUP
                        )

                    [1] => Array
                        (
                            [mimetype] => image/jpeg
                            [filename] => Outlook_Signature.jpg
                            [attachmentId] => ANGjdJ-CgZTK0oK44Q8j7TlN_JlaexxGKZ_wHFfoEB
                            [data] => 6jRXhpZgAATU0AKgAAAAgABwESAAMAAAABAAEAAAEa
                        )

                )
        )
)