通过Google API发送电子邮件 - 前提条件失败

Question

我正在尝试使用我的Google Workspace帐户在我的 Spring Boot 应用程序中发送电子邮件。 我去了Google Cloud Console，我：

1. 创建了一个新项目，然后选择了它（即 application_name_from_google_console ）
2. 启用了Gmail API
3. 创建的OAuth同意屏幕，该屏幕
4. 已导航到“凭据”，并创建了一个新的“服务corpertiralsscortenters ） ”，这给了我一封新电子邮件，我会称之为 email_address_created_when_creating_the_service_account

然后我有此代码，该代码会导致失败的前提错误：

    // invoking code
    Gmail service = buildEmailService();
    Message message = createMessage(fromEmailAddress, toEmailAddress, subject, text);
    _sendMessage(service, message);


    private Gmail buildEmailService() throws MessagingException {
        GoogleCredentials credentials = null;
        try {
            String serviceAccountJson = "{\n" +
                    "  \"type\": \"service_account\",\n" +
                    "  \"project_id\": \"lybro-355514\",\n" +
                    "  \"private_key_id\.........." 
            ;

            InputStream targetStream = new ByteArrayInputStream(serviceAccountJson.getBytes());
            credentials = ServiceAccountCredentials.fromStream(targetStream)
                    .createScoped(Collections.singletonList(GmailScopes.GMAIL_SEND))
               .createDelegated(EMAIL_ADDRESS_CREATED_WHEN_CREATING_THE_SERVICE_ACCOUNT);

        } catch (IOException e) {
            e.printStackTrace();
            throw new MessagingException(e.getMessage());
        }
        HttpRequestInitializer requestInitializer = new HttpCredentialsAdapter(credentials);

        Gmail service = new Gmail.Builder(new NetHttpTransport(),
                GsonFactory.getDefaultInstance(),
                requestInitializer)
                .setApplicationName(APPLICATION_NAME_FROM_GOOGLE_CONSOLE)
                .build();

        return service;
    }


    private void _sendMessage(Gmail service, Message message) throws MessagingException {
        try {
            // Create send message
            message = service.users().messages().send(EMAIL_ADDRESS_CREATED_WHEN_CREATING_THE_SERVICE_ACCOUNT, message).execute();
            System.out.println("Message id: " + message.getId());
            System.out.println(message.toPrettyString());
        } catch (GoogleJsonResponseException e) {
            // TODO(developer) - handle error appropriately
            GoogleJsonError error = e.getDetails();
            if (error != null && error.getCode() == 403) {
                System.err.println("Unable to send message: " + e.getDetails());
            } else {
                e.printStackTrace();
                throw new MessagingException(e.getMessage());
            }
        } catch (IOException e) {
            e.printStackTrace();
            throw new MessagingException(e.getMessage());
        }
    }

使用此代码，我会收到以下错误：

javax.mail.MessagingException: 400 Bad Request POST https://gmail.googleapis.com/gmail/v1/users/[email protected]/messages/send {   "code": 400,   "errors": [
    {
      "domain": "global",
      "message": "Precondition check failed.",
      "reason": "failedPrecondition"
    }   ],   "message": "Precondition check failed.",   "status": "FAILED_PRECONDITION" }

Answer 1

createDelegated(EMAIL_ADDRESS_CREATED_WHEN_CREATING_THE_SERVICE_ACCOUNT)

您应该将其设置的电子邮件是您已配置委托的工作空间帐户上用户的电子邮件。

createDelegated("[email protected]")

发送的发送也应从您的域上的用户发送。服务的方式对您进行预先配置的方式来处理他们在域上模仿用户。这样，服务帐户假装是该用户。

如果您尚未阅读此信息：我强烈建议这样做。