Introduction

This documentation will guide you in writing Flow Modules for the Crosser EdgeNode.

Lets start with covering the basic nomenclature & concept.

What´s a Module?

A Module is the smallest part of a Flow. Basically we have 3 types of modules

Module UI

When building modules with this SDK a UI is built automatically based on the settings specified, see Module Settings

Input Modules

Note

Input Modules will either create data within it-self, collect data from a data source or receive data from the outside world like HTTP, MQTT, WebSocket etc. Regardless of producing, collecting or receiving data, the Input Modules purpose is to serve the flow with data to process.

These modules can pass data to Function Modules and Output Modules, but never to another Input Module

Function Modules

Note

Function Modules can be very complex, but they all have in common that they will receive data and at some point pass data to the next module(s) in the flow. Receiving and sending is not necessarily a 1 to 1 relationship.

These modules can pass data to other Function Modules and Output Modules, but never to an Input Module

Output Modules

Note

Output Modules will be located at the end of the flow. They will receive data from other module types and send data over protocols (HTTP, MQTT, WebSockets etc) to other applications/services and so on.

These modules should always send a result out so that we can retry if the operation failed etc.

Let´s look at a simple flow (created in our FlowStudio) with one module of each type, just to get a feeling what we are talking about.

Modules will be covered in depth later

What´s a Flow?

A flow is just a container for grouping modules together.

The EdgeNode

Based on our in-house developed real-time analytics engine, the Crosser Edge Node software allows you to collect any data source, build automated workflows to transform, analyze, and act on the data and integrate it using pre-built modules and connectors.

The FlowStudio

The Flow Studio is a drag-and-drop visual design tool where you select and connect pre-built building blocks called modules to develop your flows and the Flow Studio is a central component in Crosser Cloud.