feat: Variable JSON device readings (#4)

pyproject.toml

@@ -21,6 +21,9 @@ classifiers = [
 "Homepage" = "https://github.com/Aiky30/shed-pi"
 "Bug Tracker" = "https://github.com/Aiky30/shed-pi/issues"
 
+[tool.pytest.ini_options]
+DJANGO_SETTINGS_MODULE = "shedpi_hub_example_project.settings"
+
 [tool.black]
 exclude = '''
 /(

requirements.txt

@@ -1,20 +1,31 @@
 asgiref==3.7.2
+attrs==23.2.0
 build==0.10.0
 cfgv==3.4.0
 distlib==0.3.8
 Django==5.0.1
+exceptiongroup==1.2.0
+factory-boy==3.3.0
+Faker==22.5.0
 filelock==3.13.1
 identify==2.5.33
 iniconfig==2.0.0
+jsonschema==4.21.1
+jsonschema-specifications==2023.12.1
 nodeenv==1.8.0
 packaging==23.1
 platformdirs==4.1.0
 pluggy==1.4.0
 pre-commit==3.6.0
 pyproject_hooks==1.0.0
 pytest==7.4.4
+pytest-django==4.7.0
+python-dateutil==2.8.2
 PyYAML==6.0.1
+referencing==0.32.1
+rpds-py==0.17.1
 setuptools-scm==7.1.0
+six==1.16.0
 sqlparse==0.4.4
 tomli==2.0.1
 typing_extensions==4.7.1

shedpi_hub_dashboard/admin.py

@@ -1,13 +1,18 @@
 from django.contrib import admin
 
-from .models import Device, DeviceReading
+from .models import Device, DeviceModule, DeviceModuleReading
 
 
 @admin.register(Device)
 class DeviceAdmin(admin.ModelAdmin):
     list_display = ("id", "name")
 
 
-@admin.register(DeviceReading)
-class DeviceReadingAdmin(admin.ModelAdmin):
+@admin.register(DeviceModule)
+class DeviceModuleAdmin(admin.ModelAdmin):
+    pass
+
+
+@admin.register(DeviceModuleReading)
+class DeviceModuleReadingAdmin(admin.ModelAdmin):
     pass

shedpi_hub_dashboard/forms/fields.py

@@ -0,0 +1,25 @@
+import json
+
+from django.forms import JSONField as JSONFormField
+from django.forms import widgets
+
+
+class PrettyJSONWidget(widgets.Textarea):
+    def format_value(self, value):
+        # Prettify the json
+        value = json.dumps(json.loads(value), indent=2, sort_keys=True)
+
+        # Calculate the size of the contents
+        row_lengths = [len(r) for r in value.split("\n")]
+        content_width = max(len(row_lengths) + 2, 20)
+        content_height = max(max(row_lengths) + 2, 45)
+
+        # Adjust the size of TextArea to fit to content
+        self.attrs["rows"] = min(content_width, 60)
+        self.attrs["cols"] = min(content_height, 155)
+
+        return value
+
+
+class PrettyJsonFormField(JSONFormField):
+    widget = PrettyJSONWidget

shedpi_hub_dashboard/migrations/0001_initial.py

@@ -1,6 +1,7 @@
-# Generated by Django 5.0.1 on 2024-01-17 22:11
+# Generated by Django 5.0.1 on 2024-01-23 19:02
 
 import django.db.models.deletion
+import shedpi_hub_dashboard.models
 import uuid
 from django.db import migrations, models
 
@@ -28,7 +29,35 @@ class Migration(migrations.Migration):
             ],
         ),
         migrations.CreateModel(
-            name="DeviceReading",
+            name="DeviceModule",
+            fields=[
+                (
+                    "id",
+                    models.UUIDField(
+                        default=uuid.uuid4,
+                        editable=False,
+                        primary_key=True,
+                        serialize=False,
+                    ),
+                ),
+                ("name", models.CharField(max_length=20)),
+                ("location", models.CharField(max_length=50)),
+                (
+                    "schema",
+                    shedpi_hub_dashboard.models.PrettySONField(blank=True, null=True),
+                ),
+                (
+                    "device",
+                    models.ForeignKey(
+                        help_text="A device which manages the module.",
+                        on_delete=django.db.models.deletion.CASCADE,
+                        to="shedpi_hub_dashboard.device",
+                    ),
+                ),
+            ],
+        ),
+        migrations.CreateModel(
+            name="DeviceModuleReading",
             fields=[
                 (
                     "id",
@@ -39,16 +68,17 @@ class Migration(migrations.Migration):
                         verbose_name="ID",
                     ),
                 ),
-                ("device_temp", models.CharField(max_length=8)),
-                ("probe_temp", models.CharField(max_length=8)),
-                ("measurement_type", models.CharField(max_length=10)),
-                ("datetime", models.DateTimeField()),
                 (
-                    "device",
+                    "data",
+                    shedpi_hub_dashboard.models.PrettySONField(blank=True, null=True),
+                ),
+                ("created_at", models.DateTimeField(auto_now_add=True)),
+                (
+                    "device_module",
                     models.ForeignKey(
                         help_text="A device whose readings were collected.",
                         on_delete=django.db.models.deletion.CASCADE,
-                        to="shedpi_hub_dashboard.device",
+                        to="shedpi_hub_dashboard.devicemodule",
                     ),
                 ),
             ],

shedpi_hub_dashboard/models.py

@@ -1,6 +1,17 @@
 import uuid
 
 from django.db import models
+from django.db.models import JSONField
+from jsonschema import validate
+
+from shedpi_hub_dashboard.forms.fields import PrettyJsonFormField
+
+
+class PrettySONField(JSONField):
+    def formfield(self, **kwargs):
+        defaults = {"form_class": PrettyJsonFormField}
+        defaults.update(kwargs)
+        return super().formfield(**defaults)
 
 
 class Device(models.Model):
@@ -12,14 +23,48 @@ def __str__(self):
         return self.name
 
 
-class DeviceReading(models.Model):
+class DeviceModule(models.Model):
+    id = models.UUIDField(primary_key=True, default=uuid.uuid4, editable=False)
     device = models.ForeignKey(
         Device,
         on_delete=models.CASCADE,
+        help_text="A device which manages the module.",
+    )
+    name = models.CharField(max_length=20)
+    location = models.CharField(max_length=50)
+    schema = PrettySONField(null=True, blank=True)
+
+    def __str__(self):
+        return self.name
+
+
+class DeviceModuleReading(models.Model):
+    device_module = models.ForeignKey(
+        DeviceModule,
+        on_delete=models.CASCADE,
         help_text="A device whose readings were collected.",
     )
-    # TODO: Create a Json configurable engine for storage and retrieval fields¬
-    device_temp = models.CharField(max_length=8)
-    probe_temp = models.CharField(max_length=8)
-    measurement_type = models.CharField(max_length=10)
-    datetime = models.DateTimeField()
+    data = PrettySONField(null=True, blank=True)
+    created_at = models.DateTimeField(auto_now_add=True)
+
+    def validate_data(self) -> None:
+        """
+        Validates the data against the schema defined in the DeviceModule,
+        the purpose is to ensure that the data stored matches the data structure expected
+        """
+        schema = self.device_module.schema
+
+        # Only validate if a schema exists
+        if schema:
+            validate(
+                instance=self.data,
+                schema=schema,
+            )
+
+    def save(self, *args, **kwargs) -> None:
+        """
+        On save validates
+        """
+        self.validate_data()
+
+        super().save(*args, **kwargs)

shedpi_hub_dashboard/tests/test_json_schema.py

@@ -0,0 +1,98 @@
+import pytest
+from jsonschema.exceptions import SchemaError, ValidationError
+
+from shedpi_hub_dashboard.models import DeviceModuleReading
+from shedpi_hub_dashboard.tests.utils.factories import DeviceModuleFactory
+
+
+@pytest.mark.django_db
+def test_schema_validation_happy_path():
+    """
+    The data validation should succeed when the schema is valid
+    """
+    schema = {
+        "$id": "https://example.com/person.schema.json",
+        "$schema": "https://json-schema.org/draft/2020-12/schema",
+        "title": "Person",
+        "type": "object",
+        "properties": {
+            "firstName": {"type": "string", "description": "The person's first name."},
+            "lastName": {"type": "string", "description": "The person's last name."},
+            "age": {
+                "description": "Age in years which must be equal to or greater than zero.",
+                "type": "integer",
+                "minimum": 0,
+            },
+        },
+    }
+    data = {"firstName": "John", "lastName": "Doe", "age": 21}
+    device_module = DeviceModuleFactory(schema=schema)
+
+    reading = DeviceModuleReading(device_module=device_module, data=data)
+
+    # By default no validation error is raised
+    reading.save()
+
+
+@pytest.mark.django_db
+def test_json_schema_invalid_data():
+    schema = {
+        "$id": "https://example.com/person.schema.json",
+        "$schema": "https://json-schema.org/draft/2020-12/schema",
+        "title": "Person",
+        "type": "object",
+        "properties": {
+            "age": {
+                "description": "Age in years which must be equal to or greater than zero.",
+                "type": "integer",
+                "minimum": 0,
+            }
+        },
+    }
+    data = {"age": 21}
+    updated_data = {"age": "Some text"}
+    device_module = DeviceModuleFactory(schema=schema)
+    reading = DeviceModuleReading(device_module=device_module, data=data)
+
+    # No error occurs with valid data
+    reading.save()
+
+    # With invalid data it now throws a validation error
+    with pytest.raises(ValidationError):
+        reading.data = updated_data
+        reading.save()
+
+
+@pytest.mark.django_db
+def test_json_schema_update_with_invalid_data():
+    schema = {
+        "$id": "https://example.com/person.schema.json",
+        "$schema": "https://json-schema.org/draft/2020-12/schema",
+        "title": "Person",
+        "type": "object",
+        "properties": {
+            "age": {
+                "description": "Age in years which must be equal to or greater than zero.",
+                "type": "integer",
+                "minimum": 0,
+            }
+        },
+    }
+    data = {"age": "Some text"}
+    device_module = DeviceModuleFactory(schema=schema)
+    reading = DeviceModuleReading(device_module=device_module, data=data)
+
+    with pytest.raises(ValidationError):
+        reading.save()
+
+
+@pytest.mark.django_db
+def test_json_schema_invalid_schema():
+    schema = {"type": 1234}
+    data = {"firstName": "John", "lastName": "Doe", "age": 21}
+
+    device_module = DeviceModuleFactory(schema=schema)
+    reading = DeviceModuleReading(device_module=device_module, data=data)
+
+    with pytest.raises(SchemaError):
+        reading.save()

shedpi_hub_dashboard/tests/utils/factories.py

@@ -0,0 +1,35 @@
+from typing import ClassVar
+from uuid import uuid4
+
+import factory
+from factory.django import DjangoModelFactory
+
+from shedpi_hub_dashboard.models import Device, DeviceModule, DeviceModuleReading
+
+
+class DeviceFactory(DjangoModelFactory):
+    class Meta:
+        model = Device
+
+    id = factory.LazyFunction(lambda: str(uuid4()))
+    name = factory.Faker("word")
+    location = factory.Faker("word")
+
+
+class DeviceModuleFactory(DjangoModelFactory):
+    class Meta:
+        model = DeviceModule
+
+    id = factory.LazyFunction(lambda: str(uuid4()))
+    device = factory.SubFactory(DeviceFactory)
+    name = factory.Faker("word")
+    location = factory.Faker("word")
+    schema: ClassVar[dict] = {}
+
+
+class DeviceModuleReadingFactory(DjangoModelFactory):
+    class Meta:
+        model = DeviceModuleReading
+
+    device_module = factory.SubFactory(DeviceModuleFactory)
+    data: ClassVar[dict] = {}