Ocarina

A Python browser test automation framework built on Railway Oriented Programming (ROP).

Overview

Ocarina is a pure-Python framework that provides a declarative DSL for composing browser tests.

Its defining characteristic is that every test step is a link in a Railway chain: on failure, the rest of the chain short-circuits and the error is captured as a value rather than propagated as an exception.

This keeps test code flat and the failure path explicit.

Notable features:

• Railway-based action chains with first-class success/failure handlers.
• Hierarchical test orchestration: Test → TestSuite → TestCampaign → TestCycle.
• Parallel execution with a thread-safe WebDriver pool.
• Automatic retries on transient errors.
• Conditional branching via match_page for pages that can render in multiple states.
• Fluent assertion chains via validate.
• Built-in reporters: pretty-print (ANSI), JSON, DOCX proof documents, timing, screenshots.
• Framework-agnostic POMBase; the Selenium integration is one of several possible adapters.
• Ships its own test runner: Ocarina is NOT a pytest plugin.

Requirements

• Python 3.14+
• (SELENIUM) A matching WebDriver binary on disk (chromedriver, geckodriver, msedgedriver) for the browser you intend to use. Safari uses the native macOS safaridriver and needs no binary on disk.

Installation

pip install ocarina

Core concepts

• POM — page objects subclass POMBase; the base class is browser-agnostic.
• Scenario — a factory (driver, logger) -> Scenario(test_chain, setup, teardown, watchers) built from Scenario.
• Railway chain — actions are wrapped with create_act, which returns a builder with .failure(...), .success(...), and .execute().
• drive_page — drive_page composes multiple acts into a single chain.
• match_page — match_page branches on which of several states a page is in.
• validate — validate is a fluent assertion chain with alternatives and aggregated errors.
• Test orchestrators — Test (one case), TestSuite (parallel + retry policy), TestCampaign (sequential suites), TestCycle (smoke campaigns before main campaigns).

CLI flags (opinionated Selenium launcher)

Parsed by create_selenium_auto_cli_store. Headless mode is the default; use --not-headless to opt out.

Reporting

The opinionated/plugins/reports package ships four reporters that can be passed to bootstrap via run_plugins:

• pretty-print — hierarchical ANSI summary on stdout.
• JSON results — structured results.
• DOCX proofs — Word document assembled from logs (requires FileLogger).
• timing — context manager that prints total test duration.

Screenshots are captured automatically on failure (when autoscreen_on_fail=True on a suite) and can also be triggered explicitly through the ITakeScreenshot port.

Full example

For a complete, runnable project:

• CI workflow,
• Real page objects,
• OTP-based login coordinated through Redis,
• Data-driven suites,
• File upload tests,
• Chaos scenarios

See ocarina-example.

Development

From a clone of this repo:

make install              # create .venv and install with dev deps
make test                 # pytest + coverage + allure results
make check-coding-style   # mypy + ruff
make ruff-format          # apply formatting
make serve-htmlcov        # open the HTML coverage report
make serve-allure         # open the Allure report

License

MIT — Igor Casanova.

Built by @mojo-molotov
Fueled by figatellu and Квас.