The Start element is used to mark the starting point of the Process. A Start element contains a single Trigger configuration. Multiple Start elements can exist in the root level of the Process, but they all have to lead to the same element.
Start elements also exist e.g. within Scopes. A Start element within a Scope does not contain a Trigger configuration, it's only used to mark the starting point of the Scope.
Triggers are registered by the Agent and can only activate if the triggering event is registered by the hosting server.
Triggers are an integral part of any Frends Process as they are the way a process can be started dynamically based on an event that the Agent is able to receive. The trigger also acts as a starting point for the process and the first step in the Process diagram.
These events can include:
A file is created to a designated folder
A webservice call is received by the Agent
A message appears in a queue the Agent is subscribed to
A schedule is activated in it's time window
A manual message is sent by the user through the Frends UI
This means that if you are creating a REST API you should use and configure an HTTP Trigger or an API trigger as the start event for that integration process. Likewise in the case of a batch job you should most likely use a Schedule or a File Trigger.
Using Triggers
Triggers are used when developing an integration process and they are the first element in the process editor canvas. You can then configure the Trigger to match the integration scenario that is being developed.
Note that you can have as many Triggers as you would like in any process and you can combine different Trigger types together. This means that you can create an integration process that is run whenever a file is created to a folder AND at least every 6 hours.
Triggers also use the #hashtag notation to offer relevant information about the event that initiated the Trigger, as an example the File Trigger offers the name and metadata of the file that it was triggered from. You can then use this information to build logic in the process itself.
Different Trigger Types
Currently Frends Supports following triggers:
The type of Trigger that started the process can be checked by reference #trigger.type. It can have values as a string:
ManualTrigger
FileWatchTrigger
QueueTrigger
ScheduleTrigger
ServiceBusMessageTrigger
HttpTrigger
HttpApiTrigger
ConditionalTrigger