Loopback mechanism for file adapter service in ACE V12.0.0.6
In earlier ACE versions, the message flow file nodes would only process a single file at a time. The input directory would be scanned for the following file, and so data that one file would be propagated downstream to the remainder of the message flow. And for the processing of multiple files at a time is getting complex, previously we perform a Loopback mechanism with help of ESQL code.
When we enter into ACE v12.0.6.0, here we do not need to use code to process multiple files process at a time. This one was replaced by facilitating file exists & file iterator nodes. Added list mode property for the file exists node and added file iterator node in the message palate. Now, if the new list mode property is ticked, then information regarding multiple files will be sent downstream as part of the local environment of a single message flow propagation.
File Iterator node:
The purpose of the file iterator node is to have an easy method of interacting with this local environment structure without the flow developer needing to write any looping logic. The file iterator node processes the list of files and for each entry in the list, propagates a local environment that is compatible with driving the behavior of a subsequent file read node to read and parse that specific file. The file iterator node allows each file to be processed one at a time.
The file iterator node allows each file to be processed one at a time. If an exception occurs for a particular time of propagation, the exception is held, and therefore the remaining file entries are processed to completion.
Here, I developed one API for file adopter which consists of the file exists, file Iterator, file read, and compute file output nodes and configure the properties like directories and tick the list mode. Whenever places multiple files in the file exist node directory. It captures all the file’s metadata info and passes it to the file iterator node. The file iterator node iterates the files in a loop and is sent to the file read node. Fie read the node to process the files and processes all the files and places them in the file output directory.