Course Introduction · Designing Trigger-Based Flows
Sets up the mindset before the three Mini Projects — a Trigger is the starting point that defines when and why a Flow Path begins running — and introduces each Trigger type and how to choose one for the job.
This chapter has no Workshop to build. It is about adjusting how you think before the three Mini Projects. In the basic course you built straight-line Flows that run from start to finish. Here we shift the question to "when should this Flow start running, and why?" — and the answer to all of it lives in the Trigger.
A Trigger is not just for splitting Flows apart
Many people assume a Trigger only separates one Flow from another. It does more than that.
The core idea of this chapter
A Trigger does not only split Flows apart — it is the starting point that defines when and why that Flow Path begins running.
A single Flow can contain several Flow Paths, each starting from a different Trigger, and each Trigger responds to a different event.
Trigger A → HTTP Communication Flow
Trigger B → Email Notification Flow
Trigger C → Production Line FlowThinking this way, Flow design starts from the right question — "what should set this Flow off?" — before you think about the Nodes that come after it.
Trigger types in NARA
NARA has several Trigger types for different kinds of work. Choosing the right one is the heart of this course.
| Trigger | Starts the Flow when | Good for |
|---|---|---|
| Dashboard Trigger | A user acts from the Dashboard | Letting a person start it manually, e.g. during testing |
| Deploy Trigger | The project is deployed | Setup or preparing state when the system starts |
| HTTP Request Polling Trigger | It polls an endpoint on a schedule | Checking an external API's status periodically |
| MQTT Subscribe Trigger | A message arrives on a Topic | Receiving data from IoT devices |
| Recurring Trigger | A scheduled time is reached | Work that repeats on a schedule |
| Time Interval Trigger | A set interval elapses | Work that loops every so often |
| Webhook Trigger | An HTTP Request hits an Endpoint | Receiving events from external systems in real time |
| WebSocket Server Trigger | A connection or message comes over WebSocket | Two-way, real-time communication |
A clear example is the Webhook Trigger, which starts a Flow only when an HTTP Request arrives at its Endpoint. NARA's own basic course uses a Time Interval Trigger as the start of a Flow Path before handing off to the next Node.
Core concepts used throughout the course
This chapter lays the groundwork all three Mini Projects draw on: Flow and Flow Path, the Trigger as the starting point, the Trigger-based way of working, the difference between Manual, Scheduled and Event-driven Flows, the difference between Control Flow and Data Flow, separating Input, Process and Output, splitting Flows by responsibility, choosing a Trigger to fit the situation, and testing each path independently.
How a Flow Path works
Whatever the task, a single Flow Path usually has the same working shape: it starts from a Trigger, receives or creates data, processes and decides, takes action, then ends or waits for the next Trigger.
Trigger
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Receive or Create Data
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Process and Decision
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Action or Output
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End, Stop or Wait for Next TriggerOnce this shape is clear, the three Mini Projects that follow are the same shape applied to different kinds of work.
Ready to go
Head to Mini Project 1 · HTTP Connection to build your first Flow that connects to an external system.
Intermediate Course
Practice designing Flows on NARA through three independent Mini Projects — connecting over HTTP, sending automated email notifications, and simulating a production line process.
Mini Project 1 · HTTP Connection
Practice building a Flow that communicates with an external program or service over HTTP — understanding the Request–Response pattern, sending and receiving data, and handling the result.