Azure虚拟机部署Spring Boot应用调用SendGrid发件失败（401错误）

在Azure虚拟机上部署Spring Boot应用后，无法通过SendGrid发送邮件通知，但本地运行该应用时邮件发送完全正常。已尝试使用SendGrid的受限权限和全权限API Key，调用时均返回401错误，提示授权凭证无效、过期或已撤销。

401
{"errors":[{"message":"The provided authorization grant is invalid, expired, or revoked","field"
,"help"
}]}

{Strict-Transport-Security=max-age=600; includeSubDomains, Server=nginx, Access-Control-Allow-Origin=https://sendgrid.api-docs.io, Access-Control-Allow-Methods=POST, Connection=keep-alive, X-No-CORS-Reason=https://sendgrid.com/docs/Classroom/Basics/API/cors.html, Content-Length=116, Access-Control-Max-Age=600, Date=Wed, 19 Jun 2024 17:54:06 GMT, Access-Control-Allow-Headers=Authorization, Content-Type, On-behalf-of, x-sg-elas-acl, Content-Type=application/json}

server.port=9090

spring.datasource.username=dbuser
spring.datasource.password=pass123
spring.datasource.url=jdbc:postgresql://127.0.0.1:5432/aimodosia

# auto generate sql and update db schema at startup
spring.jpa.generate-ddl=true
spring.jpa.hibernate.ddl-auto=update

#show and format sql
spring.jpa.show-sql=true
spring.jpa.properties.hibernate.format_sql=true

#dialect
spring.jpa.properties.hibernate.dialect= org.hibernate.dialect.PostgreSQLDialect


# App Properties
app.jwtSecret=123esef
app.jwtExpirationMs=99900000

#TRY OLD MAIL
sendgrid.key=abcd

#app.sendgrid.key=abc

### Mail Properties
#spring.mail.host=smtp.sendgrid.net
#spring.mail.port=587
#spring.mail.username=new-try
#spring.mail.password=${app.sendgrid.key}
#spring.mail.properties.mail.smtp.auth=true
#spring.mail.properties.mail.smtp.starttls.enable=true
#spring.mail.properties.mail.smtp.starttls.required=true

management.endpoint.health.probes.enabled=true
management.health.livenessState.enabled=true
management.health.readinessState.enabled=true

SendGrid配置类（Sendgridconfig） #

@Configuration
public class Sendgridconfig {

    @Value("${sendgrid.key}")
    private String appKey;

    @Bean
    public SendGrid sendGrid(){
        return new SendGrid(appKey);
    }
}

邮件服务类（EmailService） #

@Service
public class EmailService {

    @Autowired
    SendGrid sendGrid;

    public void sendEmail(String to, String subject, String body) throws IOException {
        Email from = new Email("it2021077@hua.gr");
        Email toEmail = new Email(to);
        Content content = new Content("text/plain", body);
        Mail mail = new Mail(from, subject, toEmail, content);

        Request request = new Request();
        try {
            request.setMethod(Method.POST);
            request.setEndpoint("mail/send");
            request.setBody(mail.build());
            Response response = sendGrid.api(request);
            System.out.println(response.getStatusCode());
            System.out.println(response.getBody());
            System.out.println(response.getHeaders());
        } catch (IOException ex) {
            throw ex;
        }
    }
}

控制器调用示例 #

@PostMapping("/{user_id}/new")
    @Secured("ROLE_SECRETARY")
    public ResponseEntity<Map<String, String>> saveDonationRequest(@PathVariable Integer user_id, @RequestBody DonationRequest donationRequest) {
        Map<String, String> response = new HashMap<>();

        if (donationRequestRepository.findByLocationAndDate(donationRequest.getLocation(), donationRequest.getDate()).isPresent()) {
            System.out.println("Donation Request already exists.");
            response.put("error", "Error. Donation Request already exists.");
            return ResponseEntity.badRequest().body(response);
        } else if (donationRequest.getDate() == null || donationRequest.getLocation().isBlank() || donationRequest.getDate().isBefore(LocalDate.now())) {
            response.put("error", "Invalid donation request details.");
            return ResponseEntity.badRequest().body(response);
        } else {
            User user = userDetailsService.getUser(user_id);
            String email = user.getEmail();
            Secretary secretary = secretaryRepository.findByEmail(email).orElse(null);
            if (secretary != null) {
                System.out.println("GDGDHFGDFG");
                donationRequest.setSecretary(secretary);
                donationRequestService.saveDonationRequest(donationRequest);

                // Send confirmation email
                try {
                    String subject = "New Donation Request Submitted";
                    String body = "A new donation request has been created for " + donationRequest.getLocation() + " on " + donationRequest.getDate() + ".";
                    emailservice.sendEmail(email, subject, body);
                } catch (IOException e) {
                    e.printStackTrace();
                    response.put("error", "Your request has been done, but mail failed to send");
                    return ResponseEntity.status(HttpStatus.INTERNAL_SERVER_ERROR).body(response);
                }

                response.put("success", "Created New Donation Request and sent confirmation email.");
                return ResponseEntity.ok(response);
            } else {
                response.put("error", "Secretary not found.");
                return ResponseEntity.badRequest().body(response);
            }
        }
    }

• 验证Azure环境中API Key的正确性：检查虚拟机内应用的配置文件或环境变量，确认sendgrid.key的值和本地测试时完全一致，无额外空格或格式错误。建议在Azure中通过环境变量注入API Key，避免明文配置的潜在问题。
• 检查SendGrid账户与Key状态：登录SendGrid后台，确认账户未被限制或暂停，API Key未被撤销。同时检查账户是否完成必要验证（如邮箱、域名验证），未验证的账户可能无法正常发送邮件。
• 确认Azure网络出站规则：检查虚拟机的网络安全组（NSG）是否允许出站访问SendGrid的API端点（api.sendgrid.com，端口443）。网络限制可能导致请求无法到达SendGrid服务器，间接返回401错误。
• 核对API Key权限：即使使用全权限Key，需确认该Key已启用Mail Send权限。在SendGrid创建API Key时，必须勾选对应的邮件发送权限选项。
• 捕获完整请求日志：在Azure环境开启应用的详细日志，记录发送邮件时的请求头（尤其是Authorization头），确认API Key是否正确携带。排查是否存在配置加载异常，导致请求未携带有效凭证。
• 直接测试SendGrid API连通性：在Azure虚拟机中用curl命令测试SendGrid API，示例如下：

  curl -X POST "https://api.sendgrid.com/v3/mail/send" \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "personalizations": [{"to": [{"email": "recipient@example.com"}]}],
    "from": {"email": "it2021077@hua.gr"},
    "subject": "Test Email",
    "content": [{"type": "text/plain", "value": "Test content"}]
  }'
  

  如果curl也返回401，说明问题出在环境或Key本身；如果curl成功，说明应用代码或配置在Azure环境中有加载异常。

内容的提问来源于stack exchange，提问作者Nafsika