使用Pushy Java库发送iOS推送报No route to host错误求助

一、网络异常排查步骤 #

针对No route to host和DNS解析失败的问题，按以下顺序排查：

• 验证网络连通性：在运行代码的机器上执行ping api.sandbox.push.apple.com或telnet api.sandbox.push.apple.com 443，确认能正常连通。如果不通，优先检查网络路由、防火墙规则。
• 检查DNS配置：用nslookup api.sandbox.push.apple.com或dig api.sandbox.push.apple.com查看域名解析结果。若解析失败，尝试切换公共DNS（如8.8.8.8）测试，或在代码中为Pushy指定自定义DNS服务器。
• 确认防火墙/安全组规则：确保服务器出站规则允许访问443端口，且放行苹果APNS沙箱环境的IP段。
• 代理配置检查：若机器需通过代理访问外网，需在ApnsClientBuilder中调用.setProxy()方法配置代理信息，否则请求无法正常发送。
• 证书有效性验证：虽然当前异常是网络问题，但仍需确认P12证书路径正确、密码无误、证书未过期且对应沙箱环境。

二、替代Java APNS库推荐 #

如果Pushy的问题无法快速解决，可考虑以下成熟库：

• Java-APNS（notnoop）：老牌稳定库，支持HTTP/2协议，同时兼容证书和Token两种认证方式，文档完善，社区活跃度高。
• APNS2 Java：轻量级HTTP/2专属APNS客户端，代码简洁高效，适合对性能有要求的项目。
• Spring Cloud Apple Push Notification：适配Spring生态的模块，可快速集成到Spring Boot项目中，简化推送配置流程。

附：问题代码与异常信息 #

代码示例

String topic = "XXX";
ApnsClient apnsClient = new ApnsClientBuilder().setApnsServer(ApnsClientBuilder.DEVELOPMENT_APNS_HOST)
        .setClientCredentials(new File(
                "apns_a5400831-a2db-480b-9487-52cfe61fc4f0.p12"),
                "Password123!")
        .build();
ApnsPayloadBuilder payloadBuilder = new SimpleApnsPayloadBuilder();
String payload = payloadBuilder.buildMdmPayload(magic);
String sanitizedToken = TokenUtil.sanitizeTokenString(deviceToken);

try {
    SimpleApnsPushNotification pushNotification = new SimpleApnsPushNotification(sanitizedToken, topic,
            payload);
    PushNotificationResponse<SimpleApnsPushNotification> pushNotificationResponse = apnsClient
            .sendNotification(pushNotification).get();

    if (pushNotificationResponse.isAccepted()) {
        if (logger.isDebugEnabled()) {
            logger.debug("testCheckin(String, String) - {}", "Push notification accepted by APNs gateway.");
        }
    } else {
        if (logger.isDebugEnabled()) {
            logger.debug("testCheckin(String, String) - {}",
                    "Notification rejected by the APNs gateway: "
                            + pushNotificationResponse.getRejectionReason());
        }

        pushNotificationResponse.getTokenInvalidationTimestamp().ifPresent(timestamp -> {
            System.out.println("	…and the token is invalid as of " + timestamp);
        });
    }
} catch (Exception e) {
    logger.warn("testCheckin(String, String) - exception ignored", e);
}

异常信息

15:55:58 WARN  [com.eatthepath.pushy.apns.ApnsChannelPool] Failed to create channel: io.netty.resolver.dns.DnsResolveContext$SearchDomainUnknownHostException: Failed to resolve 'api.sandbox.push.apple.com' and search domain query for configured domains failed as well: [lan]
    at io.netty.resolver.dns.DnsResolveContext.finishResolve(DnsResolveContext.java:1047)
    ...
Caused by: java.net.NoRouteToHostException: No route to host
    at java.base/sun.nio.ch.DatagramChannelImpl.send0(Native Method)
    ...

内容的提问来源于stack exchange，提问作者Shadowman