Implement story 1.2: config read/write/wipe

Add provisioning/config.py with read/write/wipe functions, update
conftest.py with autouse CONFIG_PATH patch fixture, write 7 tests
covering all acceptance criteria, and extend pyproject.toml
per-file-ignores so conftest.py may import from provisioning.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

_bmad-output/implementation-artifacts/1-2-configuration-read-write-wipe.md

@@ -1,6 +1,6 @@
 # Story 1.2: Configuration Read/Write/Wipe
 
-Status: ready-for-dev
+Status: review
 
 ## Story
 
@@ -20,34 +20,34 @@ So that all components share one reliable config boundary with no direct filesys
 
 ## Tasks / Subtasks
 
-- [ ] Task 1: Implement `config.read()` in `src/planemapper/provisioning/config.py` (AC: #1, #4)
-  - [ ] 1.1 Import `CONFIG_PATH` from `planemapper.constants`
-  - [ ] 1.2 Implement `read() -> dict` that opens `CONFIG_PATH` and parses JSON
-  - [ ] 1.3 Let `FileNotFoundError` propagate naturally if the file does not exist — no bare `except`
+- [x] Task 1: Implement `config.read()` in `src/planemapper/provisioning/config.py` (AC: #1, #4)
+  - [x] 1.1 Import `CONFIG_PATH` from `planemapper.constants`
+  - [x] 1.2 Implement `read() -> dict` that opens `CONFIG_PATH` and parses JSON
+  - [x] 1.3 Let `FileNotFoundError` propagate naturally if the file does not exist — no bare `except`
 
-- [ ] Task 2: Implement `config.write(data)` in `src/planemapper/provisioning/config.py` (AC: #2, #4)
-  - [ ] 2.1 Implement `write(data: dict) -> None`
-  - [ ] 2.2 Call `CONFIG_PATH.parent.mkdir(parents=True, exist_ok=True)` before writing to ensure `/etc/planemapper/` exists
-  - [ ] 2.3 Write JSON to `CONFIG_PATH` with `indent=2`
+- [x] Task 2: Implement `config.write(data)` in `src/planemapper/provisioning/config.py` (AC: #2, #4)
+  - [x] 2.1 Implement `write(data: dict) -> None`
+  - [x] 2.2 Call `CONFIG_PATH.parent.mkdir(parents=True, exist_ok=True)` before writing to ensure `/etc/planemapper/` exists
+  - [x] 2.3 Write JSON to `CONFIG_PATH` with `indent=2`
 
-- [ ] Task 3: Implement `config.wipe()` in `src/planemapper/provisioning/config.py` (AC: #3, #4)
-  - [ ] 3.1 Implement `wipe() -> None` that deletes `CONFIG_PATH` if it exists
-  - [ ] 3.2 Use `CONFIG_PATH.unlink(missing_ok=True)` so wipe is idempotent
+- [x] Task 3: Implement `config.wipe()` in `src/planemapper/provisioning/config.py` (AC: #3, #4)
+  - [x] 3.1 Implement `wipe() -> None` that deletes `CONFIG_PATH` if it exists
+  - [x] 3.2 Use `CONFIG_PATH.unlink(missing_ok=True)` so wipe is idempotent
 
-- [ ] Task 4: Update `tests/conftest.py` with `CONFIG_PATH` patch fixture (AC: #4)
-  - [ ] 4.1 Add a `monkeypatch` fixture (or autouse session fixture) that patches `planemapper.provisioning.config.CONFIG_PATH` to `tmp_path / "config.json"` for every test
-  - [ ] 4.2 Confirm the fixture is applied so no test ever touches `/etc/planemapper/`
+- [x] Task 4: Update `tests/conftest.py` with `CONFIG_PATH` patch fixture (AC: #4)
+  - [x] 4.1 Add a `monkeypatch` fixture (or autouse session fixture) that patches `planemapper.provisioning.config.CONFIG_PATH` to `tmp_path / "config.json"` for every test
+  - [x] 4.2 Confirm the fixture is applied so no test ever touches `/etc/planemapper/`
 
-- [ ] Task 5: Write tests in `tests/provisioning/test_config.py` covering all 4 ACs (AC: #1, #2, #3, #4)
-  - [ ] 5.1 Test AC1: call `config.read()` with no file present; assert `FileNotFoundError` is raised
-  - [ ] 5.2 Test AC2: call `config.write(data)` with a valid dict; assert file exists and JSON round-trips correctly with all expected keys (`home_lat`, `home_lon`, `coverage_radius_nm`, `wifi_ssid`, `wifi_password`, `provisioned`)
-  - [ ] 5.3 Test AC3: write a config, call `config.wipe()`, assert file is gone, then assert `config.read()` raises `FileNotFoundError`
-  - [ ] 5.4 Test AC4: confirm `CONFIG_PATH` resolves inside `tmp_path` (not `/etc/planemapper/`) during test execution
+- [x] Task 5: Write tests in `tests/provisioning/test_config.py` covering all 4 ACs (AC: #1, #2, #3, #4)
+  - [x] 5.1 Test AC1: call `config.read()` with no file present; assert `FileNotFoundError` is raised
+  - [x] 5.2 Test AC2: call `config.write(data)` with a valid dict; assert file exists and JSON round-trips correctly with all expected keys (`home_lat`, `home_lon`, `coverage_radius_nm`, `wifi_ssid`, `wifi_password`, `provisioned`)
+  - [x] 5.3 Test AC3: write a config, call `config.wipe()`, assert file is gone, then assert `config.read()` raises `FileNotFoundError`
+  - [x] 5.4 Test AC4: confirm `CONFIG_PATH` resolves inside `tmp_path` (not `/etc/planemapper/`) during test execution
 
-- [ ] Task 6: Run quality gates
-  - [ ] 6.1 `pytest tests/` — all tests pass, 0 failures
-  - [ ] 6.2 `ruff check .` — zero violations
-  - [ ] 6.3 `ruff format --check .` — no formatting issues
+- [x] Task 6: Run quality gates
+  - [x] 6.1 `pytest tests/` — all tests pass, 0 failures
+  - [x] 6.2 `ruff check .` — zero violations
+  - [x] 6.3 `ruff format --check .` — no formatting issues
 
 ## Dev Notes
 

_bmad-output/implementation-artifacts/sprint-status.yaml

@@ -45,7 +45,7 @@ development_status:
   # Epic 1: Device Setup & Provisioning
   epic-1: in-progress
   1-1-project-scaffold-and-verified-entry-points: done
-  1-2-configuration-read-write-wipe: ready-for-dev
+  1-2-configuration-read-write-wipe: review
   1-3-wifi-hotspot-and-captive-portal-form: backlog
   1-4-location-resolution-icao-and-address: backlog
   1-5-provisioning-execution-tile-download-cache-validation-and-wifi-kill: backlog

pyproject.toml

@@ -40,3 +40,4 @@ select = ["E", "F", "I", "TID", "UP"]
 "src/planemapper/provisioning/*.py" = ["TID251"]
 # Tests may import from provisioning to test its public API
 "tests/provisioning/*.py" = ["TID251"]
+"tests/conftest.py" = ["TID251"]

src/planemapper/provisioning/config.py

@@ -1 +1,22 @@
-# stub
+import json
+from pathlib import Path
+
+from planemapper.constants import CONFIG_PATH as _CONFIG_PATH
+
+# Module-level reference so tests can monkeypatch this name
+CONFIG_PATH: Path = _CONFIG_PATH
+
+
+def read() -> dict:
+    with CONFIG_PATH.open() as f:
+        return json.load(f)
+
+
+def write(data: dict) -> None:
+    CONFIG_PATH.parent.mkdir(parents=True, exist_ok=True)
+    with CONFIG_PATH.open("w") as f:
+        json.dump(data, f, indent=2)
+
+
+def wipe() -> None:
+    CONFIG_PATH.unlink(missing_ok=True)

tests/conftest.py

@@ -2,7 +2,9 @@ from pathlib import Path
 
 import pytest
 
+import planemapper.provisioning.config as config_module
 
-@pytest.fixture
-def tmp_config_path(tmp_path: Path) -> Path:
-    return tmp_path / "config.json"
+
+@pytest.fixture(autouse=True)
+def patch_config_path(tmp_path: Path, monkeypatch: pytest.MonkeyPatch) -> None:
+    monkeypatch.setattr(config_module, "CONFIG_PATH", tmp_path / "config.json")

tests/provisioning/test_config.py

@@ -1,2 +1,69 @@
-def test_placeholder() -> None:
-    pass
+import json
+from pathlib import Path
+
+import pytest
+
+import planemapper.provisioning.config as config_module
+
+SAMPLE_CONFIG = {
+    "home_lat": 51.5074,
+    "home_lon": -0.1278,
+    "coverage_radius_nm": 100,
+    "wifi_ssid": "HomeNetwork",
+    "wifi_password": "s3cr3t",
+    "provisioned": False,
+}
+
+
+def test_read_raises_when_no_file_exists() -> None:
+    with pytest.raises(FileNotFoundError):
+        config_module.read()
+
+
+def test_write_creates_file_with_correct_content(tmp_path: Path) -> None:
+    config_module.write(SAMPLE_CONFIG)
+    assert config_module.CONFIG_PATH.exists()
+    with config_module.CONFIG_PATH.open() as f:
+        data = json.load(f)
+    for key in (
+        "home_lat",
+        "home_lon",
+        "coverage_radius_nm",
+        "wifi_ssid",
+        "wifi_password",
+        "provisioned",
+    ):
+        assert key in data
+    assert data["home_lat"] == 51.5074
+    assert data["wifi_ssid"] == "HomeNetwork"
+    assert data["provisioned"] is False
+
+
+def test_write_then_read_round_trips() -> None:
+    config_module.write(SAMPLE_CONFIG)
+    result = config_module.read()
+    assert result == SAMPLE_CONFIG
+
+
+def test_wipe_deletes_file() -> None:
+    config_module.write(SAMPLE_CONFIG)
+    assert config_module.CONFIG_PATH.exists()
+    config_module.wipe()
+    assert not config_module.CONFIG_PATH.exists()
+
+
+def test_wipe_then_read_raises() -> None:
+    config_module.write(SAMPLE_CONFIG)
+    config_module.wipe()
+    with pytest.raises(FileNotFoundError):
+        config_module.read()
+
+
+def test_wipe_is_idempotent() -> None:
+    # wipe on a non-existent file should not raise
+    config_module.wipe()
+    config_module.wipe()
+
+
+def test_config_path_is_in_tmp_path(tmp_path: Path) -> None:
+    assert str(config_module.CONFIG_PATH).startswith(str(tmp_path))