040-personal-flight-club/docs/adr/adr-0001-flat-module-layout-and-console-output.md

Keep the assignment's flat module layout and console output

Metadata

Key	Value
ID	ADR-0001
CrossReference	BC-001, SA-001

Version History

Date	Status	Author	Reviewer	Change	Commit
2026-10-24	Accepted	Jens Tirsvad Nielsen	AI as stand-in for S01	Initial version	52afb36

Allowed Status values: Proposed, Accepted, Rejected, Deprecated, Superseded by ADR-NNNN.

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Context

The Day 40 program is an assignment solution. Stakeholder S02 wants the assignment's file and class names (main.py, data_manager.py, flight_search.py, flight_data.py, notification_manager.py), and S03 wants a small repository (SA-001 conflicts). The Python checklist (QC-PY-001) asks for the layer folders domain, application, infrastructure and presentation, for logging instead of print, and for a Design Class Diagram.

Options considered:

1. Full clean-architecture layout with a logging set-up and a DCD. Cleanest on paper, but it hides the assignment's names behind layers and adds about four packages for five small classes.
2. Keep the Day 39 flat package src/flight_club/ with one module per assignment class, console output through print, no DCD. Small and recognisable; the layers are merged.
3. A middle way with domain/ only. Splits the two data classes from the rest and still breaks the assignment's file names.

The forces: the program is a one-shot console script whose output is the user interface ("Print a message" in the assignment), has about 300 lines and five classes, and has one delivery mechanism.

Decision

Keep option 2: one flat package with the assignment's module and class names. The modules still depend inward in practice (constants imports nothing and flight_data imports only constants; main is the composition root and the only module that wires them), console messages use print because they are the program's output, and the assignment's class list serves as the design instead of a separate DCD.

Consequences

Positive:

• S02 finds the assignment's names; S03 sees a small repository with no extra packages.
• The Day 39 code and tests carry over without a restructuring.

Negative:

• The layers domain, application, infrastructure and presentation are merged; QC-PY-001 criterion 17 is met only by this ADR.
• print is used for the program's output, so there is no log level or log file; secrets are kept out of the output by printing error types instead of error texts.
• If the program grows (a second delivery mechanism, a database), this decision must be revisited and the layers split.

Affected Artifacts

• BC-001 — keeps the Business Case scope of the assignment's classes and names.
• SA-001 — resolves the conflict between S02 and S03 and the clean-architecture folders.

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