尝试使用Java中的Gmail API发送电子邮件时出错

我想使用Gmail API(而不是JavaMail)发送电子邮件.我在论坛上阅读了很多类似的主题,但我还是有问题.

首先我读到这个：https://developers.google.com/gmail/api/guides/sending

我发现了一些方法：MimeMessage createEmail,Message createMessageWithEmail和Message sendMessage

然后我注意到我没有对象Gmail服务的定义,所以我需要一个类GmailQuickstart,它在这里：https://developers.google.com/gmail/api/quickstart/java

我实现了：类GmailQuickstart,方法Credential authorize()和方法Gmail getGmailService()

最后我写了一篇主要内容：

public static void main(final String[] args) throws MessagingException, IOException {
    String APPLICATION_NAME = "gmailProject";
    HttpTransport HTTP_TRANSPORT = new NetHttpTransport();
    JsonFactory JSON_FACTORY = new JacksonFactory();
    Credential credential = GmailQuickstart.authorize();

    String to = "frommail@gmail.com";
    String from = "tomail@gmail.com";
    String subject = "Subject";
    String bodyText = "Body";
    MimeMessage emailcontent = createEmail(to, from, subject, bodyText);
    createMessageWithEmail(emailcontent);
    Gmail service = new com.google.api.services.gmail.Gmail.Builder(HTTP_TRANSPORT, JSON_FACTORY, credential)
            .setApplicationName(APPLICATION_NAME).build();
    sendMessage(service, "me", emailcontent);
}

在此之后,我有一长串错误：

Exception in thread "main"com.google.api.client.googleapis. json.GoogleJsonResponseException: 403 Forbidden
{
  "code" : 403,
  "errors" : [ {
  "domain" : "global",
  "message" : "Insufficient Permission",
  "reason" : "insufficientPermissions"
} ],
"message" : "Insufficient Permission"
}
    at com.google.api.client.googleapis.json.GoogleJsonResponseException.from(GoogleJs nResponseException.java:146)
    at com.google.api.client.googleapis.services.json.AbstractGoogleJsonClientRequest.newExceptionOnError(AbstractGoogleJsonClientRequest.java:113)
    at com.google.api.client.googleapis.services.json.AbstractGoogleJsonClientRequest.newExceptionOnError(AbstractGoogleJsonClientRequest.java:40)
    at com.google.api.client.googleapis.services.AbstractGoogleClientRequest$1.interceptResponse(AbstractGoogleClientRequest.java:321)
    at com.google.api.client.http.HttpRequest.execute(HttpRequest.java:1065)
    at com.google.api.client.googleapis.services.AbstractGoogleClientRequest.executeUnparsed(AbstractGoogleClientRequest.java:419)
    at com.google.api.client.googleapis.services.AbstractGoogleClientRequest.executeUnparsed(AbstractGoogleClientRequest.java:352)
    at com.google.api.client.googleapis.services.AbstractGoogleClientRequest.execute(AbstractGoogleClientRequest.java:469)
    at org.actuarlib.outsourcing.mail.Mail.sendMessage(Mail.java:78)
    at org.actuarlib.outsourcing.mail.Mail.main(Mail.java:195)

我知道在堆栈上有很多关于类似错误的主题,但我不知道如何纠正它.
任何人都可以告诉我出了什么问题,或者您是否知道使用Gmail API发送电子邮件的其他方式？

解决方法:

问题是您的授权没有得到足够的许可.这行代码是问题所在：

private static final List<String> SCOPES =
        Arrays.asList(GmailScopes.GMAIL_LABELS);

如果您查看listing labels的参考,您将看到权限https://www.googleapis.com/auth/gmail.labels就足够了.

但这对于sending messages来说还不够.您可以在开发时更改SCOPES以包含https://mail.google.com/,直到您确切知道所需的权限：

private static final List<String> SCOPES =
        Arrays.asList(GmailScopes.MAIL_GOOGLE_COM);

标签：java,email,gmail,gmail-api
来源： https://codeday.me/bug/20190828/1756981.html