无法解析错误的请求400发送电子邮件与Gmail阿比服务帐户

Question

下面在这个版面错误的请求400多回应后，我已经走投无路通过服务帐户和Gmail API和端Oauth发送电子邮件时，解决问题。我曾尝试每一个解决方案似乎并不那么我猜我失去了一些东西越往上改变错误。

脚步：

• 随后的Gmail API指南代码
• 建立GCP和谷歌联系（遵循了这一启动medium.com/lyfepedia/sending-emails-with-gmail-api-and-python-49474e32c81f）
• 特别....设置服务帐户在谷歌云端控制台的项目，
• 授权域范围内的访问，
• 添加到JSON证书文件到项目中。
• 与服务帐户ID在管理控制台授权的API客户端，提供范围可能目前“电子邮件（读/写/发送）https://mail.google.com/，https://www.googleapis.com/auth/gmail.send”的每个组合

该GCP API仪表盘显示的请求被提出，但与100级％的错误。

在应用程序返回的错误：

com.google.api.client.googleapis.json.GoogleJsonResponseException: 400 Bad 
Request
{
  "code" : 400,
  "errors" : [ {
    "domain" : "global",
    "message" : "Bad Request",
    "reason" : "failedPrecondition"
  } ],
  "message" : "Bad Request"
}

而我的代码

import android.content.Context;
import android.os.AsyncTask;
import android.widget.Toast;

import com.google.api.client.extensions.android.http.AndroidHttp;
import com.google.api.client.googleapis.auth.oauth2.GoogleCredential;
import com.google.api.client.http.HttpTransport;
import com.google.api.client.json.JsonFactory;
import com.google.api.client.json.jackson2.JacksonFactory;
import com.google.api.client.util.Base64;
import com.google.api.services.gmail.Gmail;
import com.google.api.services.gmail.GmailScopes;
import com.google.api.services.gmail.model.Message;

import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.util.Arrays;
import java.util.List;
import java.util.Properties;

import javax.mail.MessagingException;
import javax.mail.Session;
import javax.mail.internet.InternetAddress;
import javax.mail.internet.MimeMessage;

public class mod_gmail_send_2 extends AsyncTask<Void, Void, String> {

    private Gmail mGmailService = null;
    private GoogleCredential mCredential;
    private Context mContext;

    private String userID = "me";
    private String emailFrom = "[email protected]"; //non specific  account?!?
    private String emailTo = "[email protected]";
    private String emailSubject = "This is the subject";
    private String emailBody = "This is the body text";
    private List<String> scopes = Arrays.asList(GmailScopes.GMAIL_SEND);

    public mod_gmail_send_2(Context myContext) {
        mContext = myContext;
    }

    @Override
    protected String doInBackground(Void... params) {

        try {
            mCredential = GoogleCredential
                    .fromStream(mContext.getResources().openRawResource(R.raw.myjsoncredentials))
                    .createScoped(scopes);
            HttpTransport transport = AndroidHttp.newCompatibleTransport();
            JsonFactory jsonFactory = JacksonFactory.getDefaultInstance();
            mGmailService = new Gmail.Builder(transport, jsonFactory, mCredential).build();
            MimeMessage mMimeMessage = createEmail(emailTo, emailFrom, emailSubject, emailBody);
            sendMessage(mGmailService, userID, mMimeMessage);

        }catch(Throwable e){
            return e.getLocalizedMessage();
        }
        return "Success";
    }

    public static Message sendMessage(Gmail service,String userId,MimeMessage emailContent) throws MessagingException, IOException {
        Message message = createMessageWithEmail(emailContent);
        message = service.users().messages().send(userId, message).execute();
        System.out.println("Message id: " + message.getId());
        System.out.println(message.toPrettyString());
        return message;
    }

    public static MimeMessage createEmail(String to,String from,String subject,String bodyText) throws MessagingException {
        Properties props = new Properties();
        Session session = Session.getDefaultInstance(props, null);
        MimeMessage email = new MimeMessage(session);
        email.setFrom(new InternetAddress(from));
        email.addRecipient(javax.mail.Message.RecipientType.TO,new InternetAddress(to));
        email.setSubject(subject);
        email.setText(bodyText);
        return email;
    }

    public static Message createMessageWithEmail(MimeMessage emailContent) throws MessagingException, IOException {
        ByteArrayOutputStream buffer = new ByteArrayOutputStream();
        emailContent.writeTo(buffer);
        byte[] bytes = buffer.toByteArray();
        String encodedEmail = Base64.encodeBase64URLSafeString(bytes);
        Message message = new Message();
        message.setRaw(encodedEmail);
        return message;
    }

    @Override
    protected void onPostExecute(String output) {
        Toast.makeText(mContext, output, Toast.LENGTH_LONG).show();
    }
}

任何想法，将不胜感激！！

Answer 1

看来（我站在予以纠正，或者我应该说希望被纠正），你不能从一个服务帐户发送电子邮件。与.createDelegate创建谷歌的证书时，必须而不是冒充您的gsuite域名注册了一个账号，包括它（）。

 GoogleCredential
    .fromStream(service_account_json_credentials)
    .createDelegate(your_impersonated_account@your_domain)
    .createScoped(scopes)

见https://stackoverflow.com/a/54108538/9175763

虽然你可以使用驱动API共享驱动器文件夹/文件到您的服务帐户访问，您不能委派一个私人的Gmail到您的服务帐户。 “错误：您指定的帐户谷歌地址是无效的。”

但是，您可以使用G-套件电子邮件别名作为代表从现有的G-套件电子邮件。只需将别名添加到用户在管理控制台然后打开你的G套件电子邮件帐户为正常，去设置，帐户，发送邮件，并添加你的别名。然后，您可以委托设为您的别名。