SINLI

Introduction and purpose

This package is a libre-free implementation of the SINLI standard. It builds on top of email to allow applications to communicate all sort of operations of the book sector in Spain.

There are 3 main roles in this sector:

• bookshops
• distributors
• editors

There are some other implementations of this standard, but all of those we know about are closed-source, sell for an expensive yearly license, and work only in Window$ Opressing System. Thus, small bookshops, independent editors and distributors get tied to these disrespectful technologies, and represent a huge economic drag for them.

At Devcontrol we are coding for an initiative supported by a union of these independent entities and led by Descontrol. This initiative is sharing the solution to a shared problem, and is adapting the Odoo ERP (business managing software) to be used for both distributors and bookshops. In order to be a complete replacement of those closed-source apps, we are trying to make Odoo speak SINLI ;)

Organisation and code paradigm

This repository is organized following the guidelines for python packages. The actual code source is inside src/sinli/.

This project is object oriented, and makes use of python @dataclass decorator and Enum class. Namely, the main classes are Document and Line. Each SINLI message is a Document, and each one has many Lines. These two classes must be subclassed for each different document type in a separate file, located inside src/sinli/doctype. Additionaly, Line has 2 subclasses, SubjectLine and IdentificationLine that share a common format for all document types.

SINLI details

Transport

SINLI uses the email as a common transport, but can be also fetched via FTP or other means if the parties agree to do so.

Structure

SINLI documents or messages are text-based, one file each, and line-based. There is no special syntax, instead, each line is to be processed separately, and the different fields in each line are split by their byte position in the line. Therefore, each field has a fixed lenght. In fields where the data has variable lenght, the data is padded with spaces in case of text, and ascii 0 characters in case of numerical fields.

SINLI versions

There are no standard-wide versions in SINLI. Instead, each message type has its own version number. New versions are meant to be backwards compatible to older clients. The standaring committee tries to only add fields at the end of the line, not modifying the lengths or meanings of the existing ones. However, they do not commit to it and call for "get what you can" and for a human check before importing to a system. We support implementing different versions of a document type and parsing them accordingly, but will only implement older versions in a case by case basis. SINLI editors do not like developers implementing old versions because in their opinion, it makes users lazier to update. Because of this and other reasons, older versions specifications are not publicly available.

Example code

Read a document from a SINLI file

from sinli import Document

d = Document.from_filename("/path/to/document.sinli")

Generate a SINLI document

from sinli import libros
from sinli.common import SinliCode as c
from stdnum import isbn

# Create a catalog document
catalog = libros.v10.LibrosDoc()
catalog.set_sender("sinli@publisher.example.org", "LIB12345")
catalog.set_recipient("sinli@bookshop.example.org", "LIB98765")

# Create the header line of the doc
header = libros.v10.LibrosDoc.Header()
header.PROVIDER = "Virus Editorial"
catalog.doc_lines.append(header)

# Create one book for the catalog document
book = libros.v10.LibrosDoc.Book()
book.EAN = "9788417870409"
book.ISBN_INVOICE = isbn.format(book.EAN)
book.AUTHORS = "Kristin Ross"
book.TITLE_FULL= "La forma-comuna"
book.PRICE_PV = 12.0
book.TAX_IVA = 4.0
book.PRICE_PVP = book.PRICE_PV / (1 + book.TAX_IVA / 100) # precio sin IVA
book.PRICE_TYPE = c.PRICE_TYPE.FIXED
book.PRICE_TYPE = c.PRICE_TYPE.FIXED
catalog.doc_lines.append(book)

Encode a SINLI document object to string

# SINLI message string
print(str(catalog))

# Debugging string
print(repr(catalog))

Parse a SINLI email subject line

from sinli.subject import Subject

subject_line = "ESFANDEL1234567ESFANDELIB12345ENVIO 08FANDE"
subject = Subject.from_str(subject_line)

print(f'Received a SINLI message: {subject.DOCTYPE} ({subject.get_doctype_desc()})')
# Received a SINLI message: ENVIO (Albarán de envío de distribuidora)

Build a SINLI email subject

# Use `catalog`the v10.LibrosDoc instance from the previous example
subject = catalog.build_subject()
print(f"Send email with subject '{subject}'")
# Send email with subject 'ESFANDELIB12345ESFANDELIB98765LIBROS10FANDE'

Features

Generic

• Encode and decode SINLI messages
• Easy parsing of SINLI email subjects.
• Provide intuitive ways of setting and extracting information
• Implemented in enum-based OOP in a predictable manner
• Provide English wording and original, and improved spanish explanations of fields and message types from the standards, ready to check from the IDE and to use for UIs
• Manage different document versions. Just some of them, but the mechanism is already in use to manage a diverse implementations ecosystem.
• Protect the programmer as much as possible from the hussle of the standard assuming 1 Byte character encodings.
• Testing of messages with real samples.
• Official standards documents in doc/
• Real-world message samples in res/

For bookshops

• Albarán de pedido del cliente
• Albarán de devolución
• Mensaje de texto
• Informe de liquidación de ventas
• Factura o albarán de abono
• Informe de stocks a CEGAL
• Albarán de papelería

For distributors

• Ficha del libro
• Cambio de precio
• Albarán de envío
• Factura de liquidación
• Cambio de estado de disponibilidad

Development

To be able to run the tests create your own virtualenv

virtualenv .env

And then run the installation process

make install