twigfiddle.com - Fiddle 3agw2u v3 - Created on May 18, 2018 18:40

File

{% spaceless %}
{% set mydate = date() %}
{% set randomappend = random(999) %}
{% set container_id = ((mydate | date("U")) | slice(-6)) ~ ("%03d" | format(randomappend)) %}
{% set ymd = "now"|date("ymd") %}
{% set hms = "now"|date("Hms") %}
{# Start Line 1 #}
850   00000000000Unknown               PO{{ "%-15s" | format(username) }}{# #}
{{ "%-25s"|format("PunchOut2Go") }}     {{ "%'.09d" | format(container_id) }}{# #}
{{ "%-9s" | format(container_id) }}{{ "%-9s" | format('001') }}{{ "%-12s" | format('004010') }}   {# #}
{{ ymd }}{{ hms }}X X401{{ ymd }}{{ hms | slice(0,4) }}{{ "%-15s" | format(sender_id) }}{# #}
{{ "%-15s" | format(receiver_id) }}{{ production_mode }} {{ production_mode }}{# #}
{{ "%-35s" | format(document_id) }}{{ "%-5s"|format('1') }}
{# End Line 1 #}
850   BEG0020000000SA{{ "%-22s" | format(po_number) }}{{ "%-30s" | format(release_number) }}{{ "now"|date("Ymd") }}
850   CUR00300000CY {{ currency }}
xxxxxxxxxxxx
{% endspaceless %}

Format

{
    "po_number":"VCA00123456",
    "document_id":"010011001",
    "sender_id":"",
    "receiver_id":"",
    "production_mode":"T",
    "username": "",
    "release_number": "",
    "currency": "USD",
    "container_id":"123456"
}