Affichage des cartos SAGE

envergo/geodata/admin.py

@@ -9,7 +9,7 @@
 
 from envergo.geodata.forms import DepartmentForm
 from envergo.geodata.models import Department, Map, Parcel, Zone
-from envergo.geodata.tasks import process_shapefile_map
+from envergo.geodata.tasks import generate_map_preview, process_shapefile_map
 from envergo.geodata.utils import count_features, extract_shapefile
 
 
@@ -60,7 +60,7 @@ def queryset(self, request, queryset):
 
 
 @admin.register(Map)
-class MapAdmin(admin.ModelAdmin):
+class MapAdmin(gis_admin.GISModelAdmin):
     form = MapForm
     list_display = [
         "name",
@@ -80,7 +80,7 @@ class MapAdmin(admin.ModelAdmin):
         "task_status",
         "import_error_msg",
     ]
-    actions = ["process"]
+    actions = ["process", "generate_preview"]
     exclude = ["task_id"]
     search_fields = ["name", "display_name"]
     list_filter = ["import_status", "map_type", "data_type", DepartmentsListFilter]
@@ -161,6 +161,18 @@ def process(self, request, queryset):
         )
         self.message_user(request, msg, level=messages.INFO)
 
+    @admin.action(description=_("Generate the simplified preview geometry"))
+    def generate_preview(self, request, queryset):
+        if queryset.count() > 1:
+            error = _("Please only select one map for this action.")
+            self.message_user(request, error, level=messages.ERROR)
+            return
+
+        map = queryset[0]
+        generate_map_preview.delay(map.id)
+        msg = _("The map preview will be updated soon.")
+        self.message_user(request, msg, level=messages.INFO)
+
     @admin.display(description=_("Extracted zones"))
     def zone_count(self, obj):
         count = Zone.objects.filter(map=obj).count()

envergo/geodata/migrations/0003_map_geometry.py

@@ -0,0 +1,20 @@
+# Generated by Django 4.2 on 2023-06-16 12:36
+
+import django.contrib.gis.db.models.fields
+from django.db import migrations
+
+
+class Migration(migrations.Migration):
+    dependencies = [
+        ("geodata", "0002_map_imported_zones"),
+    ]
+
+    operations = [
+        migrations.AddField(
+            model_name="map",
+            name="geometry",
+            field=django.contrib.gis.db.models.fields.MultiPolygonField(
+                geography=True, null=True, srid=4326, verbose_name="Simplified geometry"
+            ),
+        ),
+    ]

envergo/geodata/models.py

@@ -180,7 +180,9 @@ class Map(models.Model):
             choices=DEPARTMENT_CHOICES,
         ),
     )
-
+    geometry = gis_models.MultiPolygonField(
+        _("Simplified geometry"), geography=True, null=True
+    )
     created_at = models.DateTimeField(_("Date created"), default=timezone.now)
     expected_zones = models.IntegerField(_("Expected zones"), default=0)
     imported_zones = models.IntegerField(_("Imported zones"), null=True, blank=True)

envergo/geodata/tasks.py

@@ -4,29 +4,36 @@
 
 from config.celery_app import app
 from envergo.geodata.models import STATUSES, Map
-from envergo.geodata.utils import process_shapefile
+from envergo.geodata.utils import process_shapefile, simplify_map
 
 logger = logging.getLogger(__name__)
 
 
 @app.task(bind=True)
+@transaction.atomic
 def process_shapefile_map(task, map_id):
     logger.info(f"Starting import on map {map_id}")
 
     map = Map.objects.get(pk=map_id)
+
+    # Store the task data in the model, so we can display progression
+    # in the admin page.
     map.task_id = task.request.id
     map.import_error_msg = ""
     map.import_status = None
     map.save()
 
-    map.zones.all().delete()
+    # Proceed with the map import
     try:
         with transaction.atomic():
+            map.zones.all().delete()
             process_shapefile(map, map.file, task)
+            map.geometry = simplify_map(map)
     except Exception as e:
         map.import_error_msg = f"Erreur d'import ({e})"
         logger.error(map.import_error_msg)
 
+    # Update the map status and metadata
     nb_imported_zones = map.zones.all().count()
     if map.expected_zones == nb_imported_zones:
         map.import_status = STATUSES.success
@@ -38,3 +45,12 @@ def process_shapefile_map(task, map_id):
     map.task_id = None
     map.imported_zones = nb_imported_zones
     map.save()
+
+
+@app.task(bind=True)
+def generate_map_preview(task, map_id):
+    logger.info(f"Starting preview generation on map {map_id}")
+
+    map = Map.objects.get(pk=map_id)
+    map.geometry = simplify_map(map)
+    map.save()

envergo/geodata/utils.py

@@ -9,16 +9,19 @@
 
 import requests
 from django.contrib.gis.gdal import DataSource
-from django.contrib.gis.geos import GEOSGeometry
+from django.contrib.gis.geos import GEOSGeometry, MultiPolygon, Polygon
 from django.contrib.gis.utils.layermapping import LayerMapping
 from django.core.serializers import serialize
+from django.db import connection
 from django.db.models import QuerySet
 from django.utils.translation import gettext_lazy as _
 
 from envergo.geodata.models import Zone
 
 logger = logging.getLogger(__name__)
 
+EPSG_WGS84 = 4326
+
 
 class CeleryDebugStream:
     """A sys.stdout proxy that also updates the celery task states.
@@ -49,6 +52,8 @@ def write(self, msg):
 
 
 class CustomMapping(LayerMapping):
+    """A custom LayerMapping that allows to pass extra arguments to the generated model."""
+
     def __init__(self, *args, **kwargs):
         self.extra_kwargs = kwargs.pop("extra_kwargs")
         super().__init__(*args, **kwargs)
@@ -127,8 +132,6 @@ def to_geojson(obj, geometry_field="geometry"):
     srid.
     """
 
-    EPSG_WGS84 = 4326
-
     if isinstance(obj, (QuerySet, list)):
         geojson = serialize("geojson", obj, geometry_field=geometry_field)
     elif hasattr(obj, "geojson"):
@@ -191,3 +194,47 @@ def merge_geometries(polygons):
             pass
 
     return merged
+
+
+def simplify_map(map):
+    """Generates a simplified geometry for the entire map.
+
+    This methods takes a map and generates a single polygon that is the union
+    of all the polygons in the map.
+
+    We also simplify the polygon because this is for display purpose only.
+
+    We use native postgis methods those operations, because it's way faster.
+
+    As for simplification, we don't preserve topology (ST_Simplify instead of
+    ST_SimplifyPreserveTopology) because we want to be able to drop small
+    holes in the polygon.
+
+    Because of that, we also have to call ST_MakeValid to avoid returning invalid
+    polygons."""
+
+    with connection.cursor() as cursor:
+        cursor.execute(
+            """
+            SELECT
+              ST_AsText(
+                ST_MakeValid(
+                  ST_Simplify(
+                    ST_Union(z.geometry::geometry),
+                    0.0001
+                  ),
+                  'method=structure keepcollapsed=false'
+                )
+              )
+              AS polygon
+            FROM geodata_zone as z
+            WHERE z.map_id = %s
+            """,
+            [map.id],
+        )
+        row = cursor.fetchone()
+
+    polygon = GEOSGeometry(row[0], srid=EPSG_WGS84)
+    if isinstance(polygon, Polygon):
+        polygon = MultiPolygon(polygon)
+    return polygon

envergo/moulinette/models.py

@@ -3,7 +3,7 @@
 from django.contrib.gis.geos import Point
 from django.contrib.gis.measure import Distance as D
 from django.db import models
-from django.db.models import F
+from django.db.models import Case, F, When
 from django.db.models.functions import Cast
 from django.utils.translation import gettext_lazy as _
 
@@ -158,7 +158,7 @@ def __init__(self, data, raw_data):
             self.catalog["config"] = self.department.moulinette_config
 
         self.perimeters = self.get_perimeters()
-        self.criterions = self.get_criterions()
+        self.criterions_classes = self.get_criterions()
 
         # This is a clear case of circular references, since the Moulinette
         # holds references to the regulations it's computing, but regulations and
@@ -251,7 +251,12 @@ def get_perimeters(self):
             Perimeter.objects.filter(
                 map__zones__geometry__dwithin=(coords, F("activation_distance"))
             )
-            .annotate(geometry=F("map__zones__geometry"))
+            .annotate(
+                geometry=Case(
+                    When(map__geometry__isnull=False, then=F("map__geometry")),
+                    default=F("map__zones__geometry"),
+                )
+            )
             .annotate(distance=Distance("map__zones__geometry", coords))
             .order_by("distance", "map__name")
             .select_related("map", "contact")

envergo/moulinette/regulations/__init__.py

@@ -1,4 +1,5 @@
 import json
+from abc import ABC
 from dataclasses import dataclass
 from enum import Enum
 from functools import cached_property
@@ -21,18 +22,24 @@ def __str__(self):
         return self.text
 
 
-class MoulinetteRegulation:
-    """Run the moulinette for a single regulation (e.g Loi sur l'eau)."""
+class MoulinetteRegulation(ABC):
+    """Run the moulinette for a single regulation (e.g Loi sur l'eau).
 
+    This class is meant to be inherited to implement actual regulations.
+    """
+
+    # Implement this in subclasses
     criterion_classes = []
 
     def __init__(self, moulinette):
         self.moulinette = moulinette
         self.moulinette.catalog.update(self.get_catalog_data())
+
+        # Instanciate the criterions
         self.criterions = [
-            Criterion(moulinette)
-            for Criterion in self.criterion_classes
-            if Criterion in moulinette.criterions
+            perimeter.criterion(moulinette, perimeter)
+            for perimeter in moulinette.perimeters
+            if perimeter.criterion in self.criterion_classes
         ]
 
     def get_catalog_data(self):
@@ -119,7 +126,11 @@ def _get_map(self):
 
 @dataclass
 class MapPolygon:
-    """Data that can be displayed and labeled on a leaflet map as a polygon."""
+    """Data that can be displayed and labeled on a leaflet map as a polygon.
+
+    A `MapPolygon is meant to represent a single entry on a map:
+    a polygon with a given color and label.
+    """
 
     perimeters: list  # List of `envergo.geofr.Perimeter` objects
     color: str
@@ -185,7 +196,7 @@ def sources(self):
         return maps
 
 
-class MoulinetteCriterion:
+class MoulinetteCriterion(ABC):
     """Run a single moulinette check."""
 
     # Prevent template engine to instanciate the class since we sometimes want
@@ -198,9 +209,10 @@ class MoulinetteCriterion:
     # "Nomenclature réglementations & critères" document.
     CODES = ["soumis", "non_soumis", "action_requise", "non_concerne"]
 
-    def __init__(self, moulinette):
+    def __init__(self, moulinette, perimeter):
         self.moulinette = moulinette
         self.moulinette.catalog.update(self.get_catalog_data())
+        self.perimeter = perimeter
 
     def get_catalog_data(self):
         """Get data to inject to the global catalog."""

envergo/moulinette/regulations/sage.py

@@ -368,3 +368,30 @@ def result(self):
             result = RESULTS.non_disponible
 
         return result
+
+    def _get_map(self):
+        # Let's find the first map that we can display
+        perimeter = next(
+            (
+                criterion.perimeter
+                for criterion in self.criterions
+                if criterion.perimeter.map.display_for_user
+                and criterion.perimeter.map.geometry
+            ),
+            None,
+        )
+        if not perimeter:
+            return None
+
+        map_polygons = [MapPolygon([perimeter], "red", "Sage")]
+        caption = "Le projet se situe dans le périmètre du Sage."
+
+        map = Map(
+            center=self.catalog["coords"],
+            entries=map_polygons,
+            caption=caption,
+            truncate=False,
+            zoom=None,
+        )
+
+        return map