astarte_flow
astarte_flow v0.1.0

mqtt_source

  • type: producer
  • output: a message each time an MQTT message is received

An Astarte Flow source that produces data from an MQTT connection.

This block has been implemented using the Elixir tortoise MQTT client application.

Properties

  • broker_url: The URL of the broker the source will connect to. (required, string)
  • subscriptions: A non-empty list of topic filters to subscribe to. (required, string array)
  • client_id: The client id used to connect. Defaults to a random string. (optional, string)
  • ignore_ssl_errors: If true, accept invalid certificates (e.g. self-signed) when using SSL. (optional, boolean, default: false)
  • username: Username used to authenticate to the broker. (optional, string)
  • password: Password used to authenticate to the broker. (optional, string)
  • ca_cert_pem: PEM encoded CA certificate. (optional, string)
  • client_cert_pem: PEM encoded client certificate, used for mutual SSL authentication. (optional, string)
  • private_key_pem: PEM encoded private key, used for mutual SSL authentication. (optional, string)
  • subtype: A MIME type that will be put as subtype in the generated Messages. Defaults to application/octet-stream.

broker_url

 broker_url

The URL of the broker the source will connect to. The transport will be deduced by the URL: if mqtts:// is used, SSL transport will be used, if mqtt:// is used, TCP transport will be used.

subscriptions

 subscriptions

A non-empty list of topic filters to subscribe to.

client_id

 client_id

The client id used to connect. Defaults to a random string.

ignore_ssl_errors

 ignore_ssl_errors

If true, accept invalid certificates (e.g. self-signed) when using SSL.

username

 username

Username used to authenticate to the broker.

password

 password

Password used to authenticate to the broker.

ca_cert_pem

 ca_cert_pem

A PEM encoded CA certificate. If not provided, the default CA trust store provided by :certifi will be used.

client_cert_pem

 client_cert_pem

A PEM encoded client certificate, used for mutual SSL authentication. If this is provided, also private_key_pem must be provided.

private_key_pem

 private_key_pem

A PEM encoded private key, used for mutual SSL authentication. If this is provided, also client_cert_pem must be provided.

subtype

 subtype

A MIME type that will be put as subtype in the generated Messages. Defaults to application/octet-stream.

Output message

  • key: contains the MQTT topic on which the message was received
  • data: contains the payload of the message
  • type: is always binary
  • subtype: is always "application/octet-stream" but can be configured with the subtype option
  • metadata: contains the Astarte.Flow.Blocks.MqttSource.broker_url key with the broker url as value.
  • timestamp: contains the timestamp (in microseconds) the response was received.

Examples

The following example uses the mqtt_source block to connect to www.example.com MQTT broker and to subcribe to # topic.

mqtt_source
  .broker_url("mqtts://www.example.com/")
  .subscriptions(["#"])
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