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MQTT binding spec

Detailed documentation on the MQTT binding component

配置

To setup MQTT binding create a component of type bindings.mqtt. 请参阅本指南，了解如何创建和应用绑定配置。

apiVersion: dapr.io/v1alpha1
kind: Component
metadata:
  name: <NAME>
  namespace: <NAMESPACE>
spec:
  type: bindings.mqtt
  version: v1
  metadata:
  - name: url
    value: "tcp://[username][:password]@host.domain[:port]"
  - name: topic
    value: "mytopic"
  - name: qos
    value: 1
  - name: retain
    value: "false"
  - name: cleanSession
    value: "true"
  - name: backOffMaxRetries
    value: "0"

元数据字段规范

字段 必填 绑定支持 详情 示例
url Y Input/Output MQTT broker地址. 可以用secretKeyRef来引用密钥。
Use the tcp:// URI scheme for non-TLS communication.
Use the ssl:// URI scheme for TLS communication.		 "tcp://\[username\]\[:password\]@host.domain[:port]"
topic Y Input/Output The topic to listen on or send events to. "mytopic"
consumerID N Input/Output The client ID used to connect to the MQTT broker. Defaults to the Dapr app ID. "myMqttClientApp"
qos N Input/Output 表示消息的服务质量等级（QoS）， 默认值 0 Defaults to 0. 1
retain N Input/Output 定义消息是否被broker保存为指定主题的最后已知有效值 默认值为 "false" 默认值为 "false". "true", "false"
cleanSession N Input/Output Sets the clean_session flag in the connection message to the MQTT broker if "true". Defaults to "true". "true", "false"
caCert 使用TLS时需要 Input/Output Certificate Authority (CA) certificate in PEM format for verifying server TLS certificates. "-----BEGIN CERTIFICATE-----\n<base64-encoded DER>\n-----END CERTIFICATE-----"
clientCert 使用TLS时需要 Input/Output TLS client certificate in PEM format. Must be used with clientKey. "-----BEGIN CERTIFICATE-----\n<base64-encoded DER>\n-----END CERTIFICATE-----"
clientKey 使用TLS时需要 Input/Output TLS client key in PEM format. Must be used with clientCert. 可以用secretKeyRef来引用密钥。 "-----BEGIN RSA PRIVATE KEY-----\n<base64-encoded PKCS8>\n-----END RSA PRIVATE KEY-----"
backOffMaxRetries N 输入 返回错误前重试处理消息的最大次数。 Defaults to "0", which means that no retries will be attempted. "-1" can be specified to indicate that messages should be retried indefinitely until they are successfully processed or the application is shutdown. The component will wait 5 seconds between retries. "3"

使用 TLS 通信

To configure communication using TLS, ensure that the MQTT broker (e.g. mosquitto) is configured to support certificates and provide the caCert, clientCert, clientKey metadata in the component configuration. 例如:

apiVersion: dapr.io/v1alpha1
kind: Component
metadata:
  name: mqtt-binding
  namespace: default
spec:
  type: bindings.mqtt
  version: v1
  metadata:
  - name: url
    value: "ssl://host.domain[:port]"
  - name: topic
    value: "topic1"
  - name: qos
    value: 1
  - name: retain
    value: "false"
  - name: cleanSession
    value: "false"
  - name: backoffMaxRetries
    value: "0"
  - name: caCert
    value: ${{ myLoadedCACert }}
  - name: clientCert
    value: ${{ myLoadedClientCert }}
  - name: clientKey
    secretKeyRef:
      name: myMqttClientKey
      key: myMqttClientKey
auth:
  secretStore: <SECRET_STORE_NAME>

Note that while the caCert and clientCert values may not be secrets, they can be referenced from a Dapr secret store as well for convenience.

消费共享主题

当消费一个共享主题时，每个消费者必须有一个唯一的标识符。 By default, the application ID is used to uniquely identify each consumer and publisher. In self-hosted mode, invoking each dapr run with a different application ID is sufficient to have them consume from the same shared topic. However, on Kubernetes, multiple instances of an application pod will share the same application ID, prohibiting all instances from consuming the same topic. To overcome this, configure the component’s consumerID metadata with a {uuid} tag, which will give each instance a randomly generated consumerID value on start up. 例如:

apiVersion: dapr.io/v1alpha1
kind: Component
metadata:
  name: mqtt-binding
  namespace: default
spec:
  type: bindings.mqtt
  version: v1
  metadata:
  - name: consumerID
    value: "{uuid}"
  - name: url
    value: "tcp://admin:public@localhost:1883"
  - name: topic
    value: "topic1"
  - name: qos
    value: 1
  - name: retain
    value: "false"
  - name: cleanSession
    value: "false"
  - name: backoffMaxRetries
    value: "0"

绑定支持

此组件支持 输入和输出 绑定接口。

字段名为 ttlInSeconds。

  • create

相关链接