Integration & DataGlossary

What Is Event-Driven Architecture?

Also known as: EDA, event driven integration, publish subscribe, event streaming

Definition

Event-driven architecture is a design where systems publish events, such as a goods receipt posted, and other systems subscribe and react to them. It replaces constant polling and tight point-to-point calls with loosely coupled, asynchronous messages.

Event-Driven Architecture Explained

An event is a fact that something happened: an order was released, a quality hold was set, a machine stopped. A producer publishes the event to a broker, and any number of consumers subscribe. The producer does not know who listens, which keeps systems loosely coupled. Brokers include message queues such as RabbitMQ, log-based streaming platforms such as Kafka, and cloud services such as Azure Service Bus or AWS SNS and SQS.

Compared with polling, events cut latency and load. Instead of a nightly job asking the ERP what changed, the ERP or a change data capture tool emits an event when a row changes. A consumer then updates a dashboard, sends an alert or starts a workflow within seconds. The cost is operational: you must design for duplicate delivery, out-of-order events, retries and dead-letter queues.

ERPs vary in how they emit events. Infor SyteLine has an event system and sends BODs through ION. NetSuite offers user event scripts and SuiteScript hooks. SAP provides business events and IDocs. Where the ERP cannot emit events, database change capture or a polling adapter can synthesize them.

This model suits AI agents well. An agent that wakes on a 'purchase order past due' event can look up the supplier, draft an expedite note and ask a buyer to approve it, instead of someone watching a report. The agent should remain read-only or approval-gated for anything that writes back to the ERP.

Why It Matters

Events give near real-time reactions without hammering the ERP with polling queries.
Loose coupling lets teams add a new consumer, such as an AI agent, without changing the ERP.
Delivery guarantees, ordering and idempotency must be designed, or duplicates will corrupt downstream data.
It is a practical trigger layer for proactive alerts and agent workflows on top of an ERP.

In Practice

A plant wants a supervisor alerted when a work order is held for quality. The ERP's hold action emits an event to a broker. One consumer posts to the supervisor's chat channel, another updates the schedule board. During testing the same event arrives twice after a retry, so the consumers store the event ID and ignore repeats, which keeps the alert from firing twice.

Frequently Asked Questions

What is the difference between a webhook and an event broker?

A webhook is a single HTTP callback to one URL. A broker receives events and delivers them to many subscribers with queuing and retry.

Do I need Kafka for event-driven integration?

Not necessarily. A simple message queue is enough for many plants. Kafka suits high volume and replay needs.

What if my ERP cannot publish events?

Use database change capture or a scheduled adapter that detects changes and publishes events on the ERP's behalf.

How do AI agents fit with events?

Events can wake an agent to investigate and propose an action, with a human approving anything that changes ERP data.

Related Terms

Webhook

A webhook is an HTTP callback in which a source system automatically sends an HTTP request to a subscriber-provided URL when a defined event occurs, pushing notification to the consumer instead of requiring the consumer to poll for changes.

Middleware

Middleware is software that sits between applications and handles the communication, transformation, routing, and reliability concerns of moving data between them, so that the applications themselves do not need to know about each other directly.

SyteLine Event System

The SyteLine Event System is the framework's rule engine that detects defined business events - a record saved, a status changed, a threshold crossed - and runs configured handlers that send notifications, request approvals, execute SQL, or call custom logic.

AI Agent

An AI agent is a system that wraps a language model with tools, memory, and a goal so it can plan a sequence of steps, call external systems, observe the results, and iterate until the objective is met or a limit is reached.

API Gateway

An API gateway is a server that sits in front of one or more back-end services and acts as their single entry point. It authenticates callers, enforces rate limits, routes requests, and logs traffic so each back end does not have to.

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SyteLine Mongoose Framework Events Reference

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Every framework event an application event handler can subscribe to in SyteLine 9/10 and CSI on-prem, with when it fires, what it passes and the traps to avoid.

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Event	Group	Fires when	Parameters passed	Typical SyteLine use	Gotcha
IdoOnInvoke	IDO	Before an IDO method is invoked	Method name, parameter count, parameter values	Check or log calls to a specific method on an SL IDO before it runs	Read the method with METHOD() and values with METHODPARM(n); failing the handler stops the call
IdoPostInvoke	IDO	After an IDO method is invoked	Method name, parameter count, parameter values	Notify or log after a method such as a posting routine finishes	Post events cannot undo the method; use the On event to block
IdoOnItemInsert	IDO	Before an IDO item is inserted into a collection	The row being inserted	Validate a new SLCos or SLItems row, or default a value with Set Values	On events can veto the insert by failing the handler; P/PROPERTY works here
IdoPostItemInsert	IDO	After an IDO item is inserted	The inserted row	Notify a buyer when a new PO line (SLPoitems) is created	Runs after the insert; use it for follow-up actions, not validation
IdoOnItemUpdate	IDO	Before an IDO item is updated	The row plus modified flags	Require approval before CreditHold changes on SLCustomers	Use PROPERTYMODIFIED("CreditHold") so the handler only acts when that property changed
IdoPostItemUpdate	IDO	After an IDO item is updated	The updated row plus modified flags	Tell planning when a due date changes on SLCoitems	Fires per row; a bulk update of many rows fires it many times
IdoOnItemDelete	IDO	Before an IDO item is deleted	The row	Block deletion of SLItems rows unless the user is in an admin group, with a Fail action	Only properties present on the delete request are available; check with PROPERTYAVAILABLE
IdoPostItemDelete	IDO	After an IDO item is deleted	The deleted row	Write an audit row to a user-defined table after a delete	The row is gone from the database; copy what you need from the event
IdoOnLoadCollection	IDO	Before an IDO collection loads	Load flags, property names, post-query actions	Audit who queries a sensitive IDO, read the filter with FILTERSTRING()	Use P2/PROPERTY2 and FP2 here, not P; RECORDCAP() gives the cap for the query
IdoPostLoadCollection	IDO	After an IDO collection loads	The result set	Notify an admin when a load returns more than 1,000 rows	ROWS() counts rows only on this event; it returns 0 elsewhere
IdoOnUpdateCollection	IDO	Before an IDO collection update runs	Custom insert, update and delete specifications	Inspect or override custom save methods on an update request	CUSTOMINSERT, CUSTOMUPDATE and CUSTOMDELETE functions read the specifications
IdoPostUpdateCollection	IDO	After all IDO collection updates finish	None	Trigger one follow-up action per save instead of per row	No row data is passed; load what you need
IdoOnPersistFailed	IDO	When a create, update or delete throws an exception	DBErrorDataKeys count, DBErrorDataKeyList	Alert support when saves fail on an integration IDO	Fires on failure only; it does not replace normal error handling in the caller
IdoPostRequestQuarantined	IDO	When an IDO request is checked against the exclusion list	IDO, request type, method name	Log or alert on requests caught by request quarantine	Only relevant where request exclusion is configured
SessionOnLogin	Session	When a new session is requested	User name	Log logins for selected users or configurations	USERNAME() and CONFIGNAME() are meant for session events
SessionOnLoginFailed	Session	When a login attempt fails	Application name, configuration, user, originating computer name, failure details	Notify the administrator after failed logins on a production configuration	Keep the handler light; it runs on every failed attempt
SessionOnLogout	Session	When a session closes	User name	Record logout for licence or audit reporting	Sessions that time out may not behave like a clean logout; test your case
SessionOnVarChanged	Session	Before a session variable changes	Variable name and new value	Watch changes to a session variable a customization relies on	Read values with VARIABLENAME() and VARIABLEVALUE()
SessionPostVarChanged	Session	After a session variable changes	Variable name and new value	React after a variable is set	Fires often if a form sets variables on every record
TaskOnPerform	Task	Before a background task is performed	Environment attributes, profile parameters, report options, cultural formatting, task attributes, task parameters	Check parameters before a long report runs	Keep the handler light: it runs before every execution of the task
TaskPostPerform	Task	When a task completes successfully	TaskOnPerform attributes plus task result attributes	Email a finished report to a distribution list	Needs a Document Types entry for each Output Format value used, with the matching file extension (for example PDF)
TaskOnPerformFailed	Task	When a task fails	TaskOnPerform attributes plus task result attributes	Alert the owner when a nightly background task fails	Use it instead of polling Background Task History
BodPreReceive	BOD	When an inbound BOD is queued for processing	BOD verb, BOD noun, BOD XML	Screen inbound BODs before processing	If the handler fails, the BOD is not processed and BodOnReceive does not fire
BodOnReceive	BOD	When the site receives an inbound BOD through ION	BODVERB(), BODNOUN(), BODXML	Route or log inbound Sync.ItemMaster or Process.SalesOrder BODs	Use SUBXML to pull nodes from BODXML() rather than string parsing
BodOnReceiveFail	BOD	When processing of a received BOD fails	BOD verb, BOD noun, BOD XML, error message	Notify the integration owner with the error text	Pair it with a review of the inbox forms for the failed document
DataViewOnLoad	Other	When a DataView begins loading	DataView report name (initiator)	Audit use of a DataView	Newer than SyteLine 9.x; confirm the event exists in your release
DataViewPostLoad	Other	When a DataView finishes loading	DataView report name (initiator)	Log completion of a heavy DataView	Newer than SyteLine 9.x; confirm the event exists in your release
ClearServiceSessions	Other	When a Mongoose core trigger clears old service sessions	None	Rarely handled; housekeeping	Do not attach slow actions to housekeeping events

Names and parameters follow the Mongoose Framework events help topic. Internal-only events (EmailReportFromFileServer*, FileContentTest) are excluded. Event availability varies by Mongoose release: confirm the list in the Events form on your SyteLine 9.x, 10.x or CSI system before you build a handler.

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What Is Event-Driven Architecture?

Event-Driven Architecture Explained

Why It Matters

In Practice

Frequently Asked Questions

What is the difference between a webhook and an event broker?

Do I need Kafka for event-driven integration?

What if my ERP cannot publish events?

How do AI agents fit with events?

Related Terms

Webhook

Middleware

SyteLine Event System

AI Agent

API Gateway

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