处理网关获取升级包的请求(一)

先易后难，先搞边角料

首先将主题常量搞定，在MqttTopics类中新增几个主题常量，就是我们设计好的那几个主题。

// gateway OTA 升级
public static final String GATEWAY_FIRMWARE_REQUEST_TOPIC_PATTERN = BASE_GATEWAY_API_TOPIC + FIRMWARE + REQUEST + "/" + REQUEST_ID_PATTERN + CHUNK + CHUNK_PATTERN;
public static final String GATEWAY_SOFTWARE_REQUEST_TOPIC_PATTERN = BASE_GATEWAY_API_TOPIC + SOFTWARE + REQUEST + "/" + REQUEST_ID_PATTERN + CHUNK + CHUNK_PATTERN;
public static final String GATEWAY_FIRMWARE_RESPONSES_TOPIC = BASE_GATEWAY_API_TOPIC + FIRMWARE + RESPONSE + "/" + SUB_TOPIC + CHUNK + SUB_TOPIC;
public static final String GATEWAY_SOFTWARE_RESPONSES_TOPIC = BASE_GATEWAY_API_TOPIC + SOFTWARE + RESPONSE + "/" + SUB_TOPIC + CHUNK + SUB_TOPIC;
public static final String GATEWAY_SOFTWARE_ERROR_TOPIC = BASE_GATEWAY_API_TOPIC + SOFTWARE + ERROR;
public static final String GATEWAY_FIRMWARE_ERROR_TOPIC = BASE_GATEWAY_API_TOPIC + FIRMWARE + ERROR;
public static final String GATEWAY_SOFTWARE_FIRMWARE_RESPONSES_TOPIC_FORMAT = BASE_GATEWAY_API_TOPIC + "/%s" + RESPONSE + "/%s" + CHUNK + "%d";
public static final String GATEWAY_SOFTWARE_FIRMWARE_ERROR_TOPIC_FORMAT = BASE_GATEWAY_API_TOPIC + "/%s" + ERROR;

这么规范的写法，我是怎么写出来的呢？打死我，我也写不出，就得使出我的看家本领，CTRL+C CTRL+V 大法，原创我不行，模仿第一名，下面我贴出的代码都是复制粘贴而来。它们是从下面代码改出来的，即thingsboard定义好的

public static final String DEVICE_FIRMWARE_REQUEST_TOPIC_PATTERN = BASE_DEVICE_API_TOPIC_V2 + FIRMWARE + REQUEST + "/" + REQUEST_ID_PATTERN + CHUNK + CHUNK_PATTERN;
public static final String DEVICE_FIRMWARE_RESPONSES_TOPIC = BASE_DEVICE_API_TOPIC_V2 + FIRMWARE + RESPONSE + "/" + SUB_TOPIC + CHUNK + SUB_TOPIC;
public static final String DEVICE_FIRMWARE_ERROR_TOPIC = BASE_DEVICE_API_TOPIC_V2 + FIRMWARE + ERROR;
public static final String DEVICE_SOFTWARE_FIRMWARE_RESPONSES_TOPIC_FORMAT = BASE_DEVICE_API_TOPIC_V2 + "/%s" + RESPONSE + "/%s" + CHUNK + "%d";
public static final String DEVICE_SOFTWARE_REQUEST_TOPIC_PATTERN = BASE_DEVICE_API_TOPIC_V2 + SOFTWARE + REQUEST + "/" + REQUEST_ID_PATTERN + CHUNK + CHUNK_PATTERN;
public static final String DEVICE_SOFTWARE_RESPONSES_TOPIC = BASE_DEVICE_API_TOPIC_V2 + SOFTWARE + RESPONSE + "/" + SUB_TOPIC + CHUNK + SUB_TOPIC;
public static final String DEVICE_SOFTWARE_ERROR_TOPIC = BASE_DEVICE_API_TOPIC_V2 + SOFTWARE + ERROR;

主题定义好之后，还有什么小事可干呢？网关需要订阅 response、error主题，这样它才能收到响应、错误，但现在网关订阅不了，因为还没加，取消订阅也是。

在processSubscribe方法中添加主题，我多粘贴几行周围代码，这样你就能知道在哪加了。

case MqttTopics.DEVICE_SOFTWARE_RESPONSES_TOPIC:
case MqttTopics.DEVICE_SOFTWARE_ERROR_TOPIC:

// 下面4行是新增的
case MqttTopics.GATEWAY_FIRMWARE_RESPONSES_TOPIC:
case MqttTopics.GATEWAY_FIRMWARE_ERROR_TOPIC:
case MqttTopics.GATEWAY_SOFTWARE_RESPONSES_TOPIC:
case MqttTopics.GATEWAY_SOFTWARE_ERROR_TOPIC:

    registerSubQoS(topic, grantedQoSList, reqQoS);
    break;
default:
    log.warn("[{}] Failed to subscribe to [{}][{}]", sessionId, topic, reqQoS);
    grantedQoSList.add(FAILURE.value());
    break;

在processUnsubscribe方法中添加主题，我多粘贴几行周围代码，这样你就能知道在哪加了。

case MqttTopics.DEVICE_RPC_REQUESTS_SUB_SHORT_PROTO_TOPIC: {
    transportService.process(deviceSessionCtx.getSessionInfo(),
            TransportProtos.SubscribeToRPCMsg.newBuilder().setUnsubscribe(true).build(), null);
    activityReported = true;
    break;
}
// 下面4行是新增的
case MqttTopics.GATEWAY_FIRMWARE_RESPONSES_TOPIC:
case MqttTopics.GATEWAY_FIRMWARE_ERROR_TOPIC:
case MqttTopics.GATEWAY_SOFTWARE_RESPONSES_TOPIC:
case MqttTopics.GATEWAY_SOFTWARE_ERROR_TOPIC:

case MqttTopics.DEVICE_RPC_RESPONSE_SUB_TOPIC:
case MqttTopics.DEVICE_RPC_RESPONSE_SUB_SHORT_TOPIC:

到目前为止，小事好像都干完了，剩下的都是难啃的骨头，下一篇再啃骨头，啃硬骨头，我的办法就是一个字，拖，因为骨头怕熬，拖一拖，骨头就化了，因为很可能就被周围同事的高手解决了，这就是智慧。

实现 thingsboard 网关下设备 OTA 升级功能(六)

处理网关获取升级包的请求(一)

先易后难，先搞边角料