flex
Swagger Schema validation.
Decision gist · record as of 2026-08-14
No. The package is abandoned (last release 2019-09-14, last commit 2022-09-22) with high install friction and uncertain compatibility with modern Python. Swagger 2.0 itself is superseded by OpenAPI 3.x. Use only if forced to validate legacy Swagger 2.0 specs with no alternative; otherwise migrate to a maintained OpenAPI validator.AI-flagged interpretation of the facts on this page — verify before relying
Before you install
- Package targets Python 2.7 and 3.3–3.6; compatibility with modern Python versions is unverified and likely broken.
- Installation requires building from source (high friction).
- The package is abandoned—last release was 2019-09-14, last commit 2022-09-22, with no active maintenance.
License · maintenance · safety
BSD (permissive) — BSD license is permissive and poses no restrictions on use, modification, or distribution in commercial or private projects.
last release 2019-09-14 (2526 days) · last repo commit 2022-09-22 · 151 stars
0 known vulnerabilities (OSV.dev, 2026-08-14) · 92,813 downloads/mo, #13,424 on PyPI
Alternatives
Verify before relying
pip install flex==6.14.1
from flex.core import validate
validate(swagger_spec_dict)- Whether the package actually works on Python versions beyond 3.6 despite classifier claims.
- Current state of dependencies and whether they have known security issues or are themselves abandoned.
- Whether Swagger 2.0 validation is still the right choice versus migrating to OpenAPI 3.x tooling.
What it is and what it does
Flex is a validation tool for Swagger 2.0 API specifications. It validates swagger schemas themselves, performs JSON Schema validation, and checks request and response objects against their declared schemas. It includes both a Python library and a command-line interface (swagger-flex as of version 5.0.0).
The package is no longer maintained—the last release was in 2019-09-14 and the last repository commit in 2022-09-22. It was originally designed for Python 2.7 and early Python 3 versions (3.3, 3.4, 3.5, 3.6), and its compatibility with modern Python is unknown. High installation friction (source build required) combined with abandonment makes it a risky choice for new projects unless you are locked into Swagger 2.0 validation and cannot use maintained alternatives.
Use it for
- Validate a Swagger 2.0 specification file before deploying an API to ensure schema correctness.
- Test that API request and response payloads conform to their declared Swagger schema during development.
- Integrate Swagger validation into a legacy CI/CD pipeline that cannot be updated to OpenAPI 3.x tooling.
- Command-line validation of Swagger specs in build scripts using the swagger-flex CLI.
Worth the install?
AI-flagged interpretation of the facts on this page. Verify before relying on it.
No.
The package is abandoned (last release 2019-09-14, last commit 2022-09-22) with high install friction and uncertain compatibility with modern Python. Swagger 2.0 itself is superseded by OpenAPI 3.x. Use only if forced to validate legacy Swagger 2.0 specs with no alternative; otherwise migrate to a maintained OpenAPI validator.
Install
flex on PyPI
Before you install
Installation requires building from source (high friction). The package is abandoned—last release was 2019-09-14, last commit 2022-09-22, with no active maintenance. Use only if you are locked into Swagger 2.0 validation and cannot migrate to maintained alternatives.
Package targets Python 2.7 and 3.3–3.6; compatibility with modern Python versions is unverified and likely broken.
License in practice
BSD license is permissive and poses no restrictions on use, modification, or distribution in commercial or private projects.
Quickstart
pip install flex==6.14.1
from flex.core import validate
validate(swagger_spec_dict)Verify before relying
- Whether the package actually works on Python versions beyond 3.6 despite classifier claims.
- Current state of dependencies and whether they have known security issues or are themselves abandoned.
- Whether Swagger 2.0 validation is still the right choice versus migrating to OpenAPI 3.x tooling.
Package facts
| License | BSD permissive |
| Python support | Not specified |
| Install friction | High. Source build required |
| Runtime dependencies | None |
| Maintenance | Abandoned 2,526 days since the last release |
| Last repo commit | |
| First released | |
| Downloads | 92,813 / month, #13,424 on PyPI 30-day window, as of 2026-08-14 |
| Known vulnerabilities | None known OSV.dev, checked 2026-08-14 |
| Classifiers | Intended Audience :: DevelopersLicense :: OSI Approved :: BSD LicenseNatural Language :: EnglishProgramming Language :: Python :: 2Programming Language :: Python :: 2.7Programming Language :: Python :: 3Programming Language :: Python :: 3.3Programming Language :: Python :: 3.4Programming Language :: Python :: 3.5Programming Language :: Python :: 3.6 |
Evidence: flex-6.14.1.tar.gz
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