LIFO
LIFO - Last in First Out subflow
This subflow receives a series of msg.payloads and builds a queue using LIFO (Last in First out) method. The LIFO size is configurable through subflow environment variables.
This subflow was created by Smart-Tech as part of the ST-One project.
Input
msg.topic == put
Will add the msg.payload to the end of the array. Everytime a new item is received the second output sends the complete queue.
msg.topic == get
Will remove the first item of the stack and will send it in the first output
msg.topic == list
Sends the complete list on the second output.
Outputs
output 1
The first item on the top of the stack. It is sent only when msg.topic == get.
output 2
The complete queue in Array format. It is sent every time a new item is added, removed or when msg.topic == list
Status
Always show the queue size.
Environment Variables
Buffer_Size defines the size of the queue. If a new item arrives and the queue is full, the oldest item will be removed.
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