chrmorais / file-fixed

Treating fixed format files

================================= File Fixed - parser and unparser

Treating fixed format files

Overview

Arose a need to handle files with fixed data formats

As this need involve several types of records I decided to do a generic parse and unparse

To set it up you need to create a JSON file with the following attributes:

• field - field name
• type - str or int
• length - field length
• decimals - if decimals else zero

To use

>>> from fixed_files import Fixed_files
>>> ff = Fixed_files('record', dic=False, checklength=False)
>>> records = open('record.txt').readlines()
>>> rec_in = []
>>> for record in records:
...      rec_in.append(ff.parse(record))

>>> for n, r in enumerate(rec_in):
...     print ff.unparse(r) == records[n]
    
>>> rec_in[0]                                               
Out[6]: Record(tr=1, seq=1234567890.1200001, estado='SP', resto='AAAAAAAAAAAAAX')     

>>> rec_in[0] = rec_in[0]._replace(resto='Z12345678901234Z')
>>> ff.unparse(rec_in[0])
... FieldLengthOverflow: