Attaching stages to a row
Here we upload the staged file to a row and make it permanent (as long as the row exists). AmiDb supports attaching a total of 15 stages to any row. (5 positions and 3 variants for each position). This is a configuration parameter and you can increase or reduce the number of stages in production. Note this is only if you want to use position and variants naming formats to retrieve the file. You can upload any number of files to a row by using the upload file api.
Files are stored with the following internal names
_perupv00 - refers to position 0, variant 0,
_perupv01 - refers to position 0, variant 1,
_perupv02 - refers to position 0, variant 2,
_perupv10 - refers to position 1, variant 0,...

Each position can have a userdefined name. However, when you retrieve the file use the internal name.
_peruname0 - refers to the name of the position0 stage,
_peruname1 - refers to the name of the position1 stage,....

(All variants of a position have the same name)
These standardizations makes it easy for you to query back these images by position and variants without knowing the actual name of the file itself.
Let us now go back and add the stage to the customeritem