Structure¶
Definition: the structure section in a grammar defines the sequence of records in a message.
A structure is required in a grammar except for template grammars. Example of a simple structure:
structure = [
{ID:'ENV',MIN:1,MAX:999, LEVEL:[        #envelope record
    {ID:'HEA',MIN:1,MAX:9999,LEVEL:[    #header record
        {ID:'LIN',MIN:0,MAX:9999},      #line record
        ]},
    ]}
]
The example above should be read as:
- ENV-record is required; max 999 repeats.
 - ‘Nested’ under the ENV-record: HEA-record; per ENV max 9999 HEA-records; min is 1, so required.
 - Per HEA-record max 9999 LIN-records; the LIN-record is not required (MIN=0).
 
Example of a more elaborate structure:
structure = [
{ID:'ENV',MIN:1,MAX:1, LEVEL:[        #envelope record: max one per file
    {ID:'HEA',MIN:1,MAX:9999,LEVEL:[  #header record of messageat least one message per ENV, max 9999 messages
        {ID:'PAR',MIN:2,MAX:10},      #party record
        {ID:'ALC',MIN:0,MAX:9},       #allowances/charges per message
        {ID:'LIN',MIN:0,MAX:9999},    #line record
        ]},
    {ID:'TRL',MIN:1,MAX:1},           #each ENV record has a trailer record
    ]}
]
A structure consists of
A structure is a nested list of records.
Each record is a python dict.
- Per Record:
 - ID: tag of record.
 - MIN: minimum number of occurrences.
 - MAX: maximum number of occurrences.
 - LEVEL (optional): indicate nested record. The nested records are in a list of records.
 - QUERIES (optional)
 - SUBTRANSLATION (optional). Very advanced. Purpose: identify separate messages within within a standard envelope.
 
QUERIES¶
QUERIES in a structure are used to extract values from edi files before the mapping script starts. Example of an structure with QUERIES:
structure = [
{ID:'ENV',MIN:1,MAX:999,                #envelope record
    QUERIES:{
        'frompartner':  {'BOTSID':'ENV','sender':None},   #extract sender from ENV record.
        'topartner':    {'BOTSID':'ENV','receiver':None}, #extract receiver from ENV record.
        'testindicator':({'BOTSID':'ENV'},{'BOTSID':'MESSAGE','test':None}), #extract testindicator from 'deeper' level; note that this is in tuple (with brackets).
        },
    LEVEL:[
    {ID:'HEA',MIN:1,MAX:9999,LEVEL:[    #header record
        {ID:'LIN',MIN:0,MAX:9999},      #line record
        ]},
    ]}
]
Use cases of the information extracted by QUERIES: Think of frompartner, topartner, reference, testindicator etc.
To choose the right translation (QUERIES can extract frompartner, topartner, alt)
Update the database.
In a mapping script this information is inn.ta_info’.
Data in the envelope can be accessed in the mapping.
One of the most import uses is the extraction of botskey.
- Typical information extracted by QUERIES:
 - frompartner
 - topartner
 - reference
 - testindicator
 - botskey
 - alt
 
QUERIES using multiple values (concatenated)
Pass a list into the QUERIES, and the values returned will be concatenated.
QUERIES:{
    'botskey': [ ({'BOTSID':'UNH'},'BOTSID':'BGM','C002.1001':None}), ({'BOTSID':'UNH'},'BOTSID':'BGM','1004':None})],
}
QUERIES using a function
Sometimes you might need something more complex, eg. to extract a substring or do partner lookup and transformation. You can add a function in the grammar to do this and call it in QUERIES.
# frompartner needs some transformation...
import bots.transform as transform
def get_frompartner(thisnode):
     partner = thisnode.get({'BOTSID':'invoice','supplier':None})
     new_partner = transform.partnerlookup(partner,'attr1',safe=True)
     return new_partner
structure = [
{ID:'envelope',MIN:0,MAX:99999,LEVEL:[
     {ID:'invoice',MIN:0,MAX:99999,
         QUERIES:{
             'frompartner': get_frompartner,
             },
         LEVEL:[
             {ID:'line',MIN:0,MAX:99999},