Make SensorReadings a timescaledb table

config/settings/dev.py

@@ -27,7 +27,7 @@
 # override this in local_untracked.py
 DATABASES = {
     "default": {
-        "ENGINE": "django.contrib.gis.db.backends.postgis",
+        "ENGINE": "seed.backends.timescale_postgis",
         "NAME": "seed",
         "USER": "postgres",
         "PASSWORD": "postgres",

config/settings/docker.py

@@ -93,7 +93,7 @@
 # PostgreSQL DB config
 DATABASES = {
     "default": {
-        "ENGINE": "django.contrib.gis.db.backends.postgis",
+        "ENGINE": "seed.backends.timescale_postgis",
         "NAME": env_var("POSTGRES_DB"),
         "USER": env_var("POSTGRES_USER"),
         "PASSWORD": env_var("POSTGRES_PASSWORD"),

config/settings/docker_dev.py

@@ -47,7 +47,7 @@
 # PostgreSQL DB config
 DATABASES = {
     "default": {
-        "ENGINE": "django.contrib.gis.db.backends.postgis",
+        "ENGINE": "seed.backends.timescale_postgis",
         "NAME": env_var("POSTGRES_DB"),
         "USER": env_var("POSTGRES_USER"),
         "PASSWORD": env_var("POSTGRES_PASSWORD"),

config/settings/docker_test.py

@@ -13,7 +13,8 @@
 
 TESTING_MAPQUEST_API_KEY = env_var("TESTING_MAPQUEST_API_KEY", "<your_key_here>")
 
-DATABASES["default"]["ENGINE"] = "seed.backends.postgis_parallel_tests"
+TIMESCALE_DB_BACKEND_BASE = "seed.backends.postgis_parallel_tests"
+DATABASES["default"]["ENGINE"] = "seed.backends.timescale_postgis"
 DATABASES["default"]["CONN_MAX_AGE"] = 0
 
 CACHES = {

config/settings/test.py

@@ -81,8 +81,11 @@
     from config.settings.local_untracked import *  # noqa: F403
 
 # Use a test-only PostGIS backend that pauses Timescale background workers
-# while Django clones the template test database for parallel runs.
-DATABASES["default"]["ENGINE"] = "seed.backends.postgis_parallel_tests"
+# while Django clones the template test database for parallel runs. The
+# Timescale schema editor layers on top of it via TIMESCALE_DB_BACKEND_BASE so
+# hypertables are still created during test database setup.
+TIMESCALE_DB_BACKEND_BASE = "seed.backends.postgis_parallel_tests"
+DATABASES["default"]["ENGINE"] = "seed.backends.timescale_postgis"
 DATABASES["default"]["CONN_MAX_AGE"] = 0
 CACHES = {
     "default": {

config/settings/test_local_untracked.py

@@ -23,7 +23,7 @@
 # postgres DB config
 DATABASES = {
     "default": {
-        "ENGINE": "django.contrib.gis.db.backends.postgis",
+        "ENGINE": "seed.backends.timescale_postgis",
         "NAME": "seeddb",
         "USER": "postgres",
         "PASSWORD": "postgres",

pyproject.toml

@@ -11,6 +11,7 @@ dependencies = [
     "django~=6.0.6",
     # Persistence (database)
     "psycopg[binary]~=3.3.4",
+    "django-timescaledb==0.2.13",
     # Background jobs / scheduling / caching
     "celery==5.6.3",
     "django-celery-beat==2.9.0",

seed/backends/timescale_postgis/__init__.py

@@ -0,0 +1,4 @@
+"""
+SEED Platform (TM), Copyright (c) Alliance for Energy Innovation, LLC, and other contributors.
+See also https://github.com/SEED-platform/seed/blob/main/LICENSE.md
+"""

seed/backends/timescale_postgis/base.py

@@ -0,0 +1,49 @@
+"""
+SEED Platform (TM), Copyright (c) Alliance for Energy Innovation, LLC, and other contributors.
+See also https://github.com/SEED-platform/seed/blob/main/LICENSE.md
+
+TimescaleDB + PostGIS database backend for SEED.
+
+This wraps ``timescale.db.backends.postgis`` and swaps in a schema editor that
+fixes an upstream bug in the released ``django-timescaledb`` (0.2.13): its
+PostGIS ``schema.py`` references ``settings`` inside ``_create_hypertable``
+without importing it. That method is executed whenever an existing table is
+migrated into a hypertable (our ``SensorReading.timestamp`` AlterField), so the
+released package raises ``NameError: name 'settings' is not defined`` and the
+migration fails. The fix exists on the project's ``master`` branch but has not
+been released.
+
+The base backend is still configurable through ``TIMESCALE_DB_BACKEND_BASE``
+(defaults to PostGIS), so this composes with the parallel test backend used by
+the test settings.
+
+This workaround can be removed once a ``django-timescaledb`` release that
+includes the upstream fix is available.
+"""
+
+from django.conf import settings
+from timescale.db.backends.postgis.base import DatabaseWrapper as TimescaleDatabaseWrapper
+from timescale.db.backends.postgis.schema import TimescaleSchemaEditor
+
+
+class SeedTimescaleSchemaEditor(TimescaleSchemaEditor):
+    def _create_hypertable(self, model, field, should_migrate=False):
+        # Reimplemented from TimescaleSchemaEditor to reference ``settings`` from
+        # this module's namespace, which the released package fails to import.
+        self._assert_is_not_hypertable(model)
+        self._drop_primary_key(model)
+
+        partition_column = self.quote_value(field.column)
+        interval = self.quote_value(field.interval)
+        table = self.quote_value(model._meta.db_table)
+        migrate = "true" if should_migrate else "false"
+
+        if should_migrate and getattr(settings, "TIMESCALE_MIGRATE_HYPERTABLE_WITH_FRESH_TABLE", False):
+            raise NotImplementedError()
+
+        sql = self.sql_add_hypertable.format(table=table, partition_column=partition_column, interval=interval, migrate=migrate)
+        self.execute(sql)
+
+
+class DatabaseWrapper(TimescaleDatabaseWrapper):
+    SchemaEditorClass = SeedTimescaleSchemaEditor

seed/migrations/0255_alter_sensorreading_timestamp.py

@@ -0,0 +1,16 @@
+import timescale.db.models.fields
+from django.db import migrations
+
+
+class Migration(migrations.Migration):
+    dependencies = [
+        ("seed", "0254_repair_missing_primary_keys"),
+    ]
+
+    operations = [
+        migrations.AlterField(
+            model_name="sensorreading",
+            name="timestamp",
+            field=timescale.db.models.fields.TimescaleDateTimeField(interval="7 days"),
+        ),
+    ]

seed/models/sensors.py

@@ -4,6 +4,7 @@
 """
 
 from django.db import models
+from timescale.db.models.fields import TimescaleDateTimeField
 
 from seed.models import Property
 
@@ -49,7 +50,7 @@ class Meta:
 
 class SensorReading(models.Model):
     reading = models.FloatField(null=True)
-    timestamp = models.DateTimeField()
+    timestamp = TimescaleDateTimeField(interval="7 days")
     sensor = models.ForeignKey(
         Sensor,
         on_delete=models.CASCADE,