.. include:: ../_resources.rst .. _faq-application-object: ######################### Application configuration ######################### ************ Introduction ************ The core of each data acquisition application is its configuration object. ************* Configuration ************* This configuration snippet will create an application object defined as ``[amazonas]``. :: ; ----------------------------- ; Data acquisition through MQTT ; ----------------------------- [amazonas] enable = true type = application realm = amazonas mqtt_topics = amazonas/# application = kotori.daq.application.mqttkit:mqttkit_application *********** Description *********** This essentially spawns an application on the realm ``amazonas``. - The realm -- here called ``amazonas`` -- designates the "tenant" or "vendor" by means of a multi-tenant system. - Kotori will subscribe to the MQTT topic ``amazonas/#`` to receive all readings published to that topic. - When data is received, the data payload will be evaluated through the machinery defined through the software component ``kotori.daq.application.mqttkit``. This component is assembled from several baseline software components from the toolbox of Kotori. - Kotori will also signal Grafana_ in order to create some instant dashboards reflecting the telemetry fields of the measurement data just ingested. ******* Details ******* WAN addressing ============== One of the convention of the `MQTTKit communication flavor`_ is that is uses several MQTT topic segments implementing the »quadruple hierarchy strategy« in a wide-network addressing scheme like outlined within the `MQTTKit addressing scheme`_:: realm / network / gateway / node Implementation details ====================== The main workhorse is the `DAQ core router`_, which is spun up at `mqttkit.py, l. 26 `_, essentially tying all things together. The addressing scheme is implemented through the `WanBusStrategy`_ component. It will take the responsibility of properly receiving and decoding message payloads arriving on the MQTT bus according to the specific conventions implemented in there.