rewrite migration to stay compatible with sqlite

src/c3nav/mapdata/management/commands/findbeacons.py

@@ -0,0 +1,29 @@
+import numpy as np
+from django.core.management.base import BaseCommand
+
+from c3nav.mapdata.models.geometry.space import WifiMeasurement, RangingBeacon
+
+
+class Command(BaseCommand):
+    help = 'list FTM-capable APs that have been spotted'
+
+    def handle(self, *args, **options):
+        found_beacons = {}
+        # lets collect them
+        for wifi_measurement in WifiMeasurement.objects.select_related("space"):
+            for measurement_list in wifi_measurement.data:
+                for measurement in measurement_list:
+                    if measurement.get("supports80211mc", False) or measurement.get("distance", None):
+                        found_beacons.setdefault(measurement["bssid"], []).append((wifi_measurement, measurement))
+
+        # put in the ones we know
+        known = {r.bssid: r for r in RangingBeacon.objects.all()}
+
+        # lets go through them
+        for bssid, measurements in found_beacons.items():
+            print(bssid, measurements[0][1]["ssid"], known.get(bssid))
+            points = {wifi_measurement.geometry for wifi_measurement, measurement in measurements}
+            for wifi_measurement, measurement in measurements:
+                break
+                #print(f"    Space={wifi_measurement.space.title!r} RSSI={measurement['rssi']} "
+                #      f"distance={measurement.get('distance')} distance_sd={measurement.get('distance_sd')}")

src/c3nav/mapdata/migrations/0100_obstaclegroup_color_data.py

@@ -2,47 +2,32 @@
 
 from django.db import migrations
 
-sql_up = '''
--- create an obstacle group for every distinct obstacle color
-insert into mapdata_obstaclegroup (color, titles)
-select color as color,
-       json_build_object('en', concat('Color ', color)) as titles
-from
-                          (select distinct color
-                            from mapdata_obstacle
-                            where color is not null
-                            union 
-                            select distinct color
-                            from mapdata_lineobstacle
-                            where color is not null) as obstacle_colors;
+def forwards_func(apps, schema_editor):
+    ObstacleGroup = apps.get_model('mapdata', 'ObstacleGroup')
+    Obstacle = apps.get_model('mapdata', 'Obstacle')
+    LineObstacle = apps.get_model('mapdata', 'LineObstacle')
 
--- set the groups for colored obstacles to the previously created group with that color
-update mapdata_obstacle as o
-set group_id = g.id
-from mapdata_obstaclegroup g
-where g.color = o.color;
+    grouped = {}
 
-update mapdata_lineobstacle as o
-set group_id = g.id
-from mapdata_obstaclegroup g
-where g.color = o.color;
-'''
+    for obstacle in Obstacle.objects.filter(color__isnull=False):
+        grouped.setdefault(obstacle.color, []).append(obstacle)
 
-sql_down = '''
--- set obstacle color from associated group color and remove group
-update mapdata_obstacle as o
-set color = g.color, group_id = null
-from mapdata_obstaclegroup g
-where g.id = o.group_id;
+    for lineobstacle in LineObstacle.objects.filter(color__isnull=False):
+        grouped.setdefault(lineobstacle.color, []).append(lineobstacle)
 
-update mapdata_lineobstacle as o
-set color = g.color, group_id = null
-from mapdata_obstaclegroup g
-where g.id = o.group_id;
+    for color, obstacles in grouped.items():
+        group = ObstacleGroup.objects.create(
+            color=color,
+            titles={"en": f"Color {color}"}
+        )
+        for obstacle in obstacles:
+            obstacle.group = group
+            obstacle.save()
 
--- delete groups
-delete from mapdata_obstaclegroup where true;
-'''
+
+def backwards_func(apps, schema_editor):
+    ObstacleGroup = apps.get_model('mapdata', 'ObstacleGroup')
+    ObstacleGroup.objects.all().delete()
 
 
 class Migration(migrations.Migration):
@@ -52,5 +37,5 @@ class Migration(migrations.Migration):
     ]
 
     operations = [
-        migrations.RunSQL(sql_up, sql_down)
+        migrations.RunPython(forwards_func, backwards_func)
     ]