Standard BOM for Python

A Python library for creating and consuming documents in standard-bom format.

"Standard BOM" is our Siemens-internal SBOM format based on the Siemens CycloneDX Property Taxonomy, which is 100% compatible with the CycloneDX.

Every Standard BOM document is a 100% CycloneDX document, so both CycloneDX and Standard BOM formats are supported both for reading and writing SBOMs with this library.

Installation

To install the library, run following command ...

... for pip:

pip install siemens-standard-bom

... for Poetry:

poetry add siemens-standard-bom

The library provides Standard BOM parser and serializer classes. The parser class is used to read a Standard BOM from a file, and the serializer class is used to write a Standard BOM to a file.

💡 Hint: This library provides strict type checking using mypy. Using mypy with strict type checks in your own codebase is recommended to ensure type safety.

Read a Standard BOM from a JSON file

from siemens_standard_bom.parser import StandardBomParser

bom = StandardBomParser.parse("sbom.cdx.json")

Write a Standard BOM to a JSON file

from siemens_standard_bom.parser import StandardBomParser

bom = ...
StandardBomParser.save(bom, "sbom.cdx.json")

If you'd like to skip the .dependencies field in the output file, you can use the following code:

from siemens_standard_bom.parser import StandardBomParser

bom = ...
StandardBomParser.save(bom, "sbom.cdx.json", with_dependencies=False)

This will save the Standard BOM to the file without the .dependencies field, which is prohibited in the external profile.

Create a Standard BOM document programmatically

The StandardBom class wraps the cyclonedx.model.bom.Bom class from the upstream library cyclonedx-python-lib. This library provides convenience wrappers around model objects from the upstream library.

from cyclonedx.model.component import Component, ComponentType
from cyclonedx.model.contact import OrganizationalContact
from siemens_standard_bom.model import StandardBom

bom = StandardBom()
bom.add_author(OrganizationalContact(name='John Doe'))
bom.add_tool(Component(name='Sample Tool', version='1.0.0', type=ComponentType.APPLICATION))
bom.add_component(Component(name='Sample Component', version='1.2.3', type=ComponentType.LIBRARY))

You can also use the Standard BOM wrapper classes to create and edit the Standard BOM document. For example, you can do the following similar to the example abode:

from cyclonedx.model.component import Component, ComponentType
from cyclonedx.model.contact import OrganizationalContact
from siemens_standard_bom.model import StandardBom, SbomComponent

bom = StandardBom()
bom.add_author(OrganizationalContact(name='John Doe'))
bom.add_tool(SbomComponent(Component(name='Sample Tool', version='1.0.0', type=ComponentType.APPLICATION)))
bom.add_component(SbomComponent(Component(name='Sample Component', version='1.2.3', type=ComponentType.LIBRARY)))

Retrieve fields from the Standard BOM object

Once you retrieve several fields from the StandardBom object, you get the wrapped Standard BOM types for these fields. For example, the tools or components getters returns a list of SbomComponent objects:

from typing import Iterable
from siemens_standard_bom.model import SbomComponent

bom = ...
components: Iterable[SbomComponent] = bom.components
tools: Iterable[SbomComponent] = bom.tools

Setting licenses to a component

You can set licenses to a component by using the licenses setter method of the SbomComponent class. SbomComponent.licenses setter method accepts an iterable of type License which can be a LicenseExpression or a DisjunctiveLicense:

from cyclonedx.model.license import LicenseExpression

component = SbomComponent(...)
licenses = [LicenseExpression(value="MIT")]
component.licenses = licenses

Development

In order to build this library on your local PC, and/or contribute to this library, mind the following prerequisites:

• Python >=3.10, <4.0
• Poetry >= v2.0

Once you have those prerequisites you can perform following development tasks locally:

• Run the build by executing

  poetry install
  

  then

  poetry build
  

  This will generate the build artifacts under dist/ folder.

• Run all unit tests with all test cases and static code analysis

  poetry run tox run
  

  This will run all the tests for all supported Python versions as well as static linting and type checking.

License

This project is Inner Source under the MIT license (SPDX-License-Identifier: MIT).

Copyright (c) Siemens AG 2019-2025 ALL RIGHTS RESERVED