#99 Port to GeoNode 4 - fix migrations

rndt/migrations/0003_layerrndt.py

@@ -1,79 +1,49 @@
 # Generated by Django 2.2.16 on 2021-02-17 10:57
 import logging
 
-import django.db.models.deletion
+from django.db.models.deletion import CASCADE
 from django.db import migrations, models
-from django.db import DatabaseError
-from django.db import connections
-from django.db.migrations.recorder import MigrationRecorder
 
 logger = logging.getLogger(__name__)
 
-
-def migration_applied(app_label: str, migration_name: str) -> bool:
-    for alias in connections:
-        try:
-            if (MigrationRecorder.Migration.objects
-                    .using(alias)
-                    .filter(app=app_label, name=migration_name)
-                    .exists()):
-                return True
-        except DatabaseError as e:
-            # django_migrations table does not exist -> no migrations applied
-            logger.info("Error retrieving migrations", exc_info=e)
-            pass
-
-    return False
-
-
 try:
     from geonode.layers.models import Layer
-    logger.debug("Linking LayerRNDT to Layer (<4.x)")
+    logger.error("Linking LayerRNDT to Layer (<4.x) -- we're not supposed to be here!")
+    # we're on branch 4.x and should not have the Layer class, anyway here it is
+    # we can't iuse this model in 4.x bc class Layer does not exist anymore
+
+    class Migration(migrations.Migration):
+        dependencies = [
+            ('rndt', '0001_initial'),
+            ('layers', '24_initial')
+        ]
+
+        operations = [
+            migrations.CreateModel(
+                name='LayerRNDT',
+                fields=[
+                    ('id', models.AutoField(auto_created=True, primary_key=True, serialize=False, verbose_name='ID')),
+                    ('constraints_other', models.TextField(default=None, null=True)),
+                    ('layer', models.OneToOneField(on_delete=CASCADE, to='layers.Layer')),
+                ],
+                options={
+                    'verbose_name_plural': 'Layer RNDT',
+                    'ordering': ('layer', 'constraints_other'),
+                },
+            ),
+        ]
 
-    fk_pointed_class = 'layers.Layer'
-    base_dep = ('layers', '24_initial')
 except ImportError:
     try:
         from geonode.layers.models import Dataset
-        logger.debug("Linking LayerRNDT to Dataset (>=4.x)")
-        fk_pointed_class = 'layers.Dataset'
+        logger.debug("Deferring LayerRNDT creation on geonode>=4.x)")
+        # when running on 4.x, we're going to deal with the RNDTLayer model in a brand new migration (0006)
+
+        class Migration(migrations.Migration):
+            dependencies = [('rndt', '0001_initial'), ]
+            operations = [migrations.RunPython(migrations.RunPython.noop, migrations.RunPython.noop)]
 
-        if migration_applied('rndt', '0003_layerrndt'):
-            # RNDT already installed in 3.3.x - we're migrating from 3.3 to 4.x
-            # we're not supposed to do anything in the DB, since the table is already there,
-            # and the FK will be automatically migrated in the renaming in 0038_rename_layer_dataset.
-            # We can't put 0038_rename_layer_dataset as a dependency or we'll get:
-            # -- django.db.migrations.exceptions.InconsistentMigrationHistory: Migration rndt.0003_layerrndt is applied
-            # -- before its dependency layers.0038_rename_layer_dataset on database 'default'.
-            base_dep = None
-        else:
-            # we need the dataset table created by the base migration
-            base_dep = ('layers', '0038_rename_layer_dataset')
-        logger.debug(f"Depending on {base_dep}")
     except ImportError:
         raise Exception('Can not find base class for LayerRNDT')
 
 
-class Migration(migrations.Migration):
-
-    dependencies = [
-        ('rndt', '0001_initial'),
-    ]
-
-    if base_dep:
-        dependencies.append(base_dep)
-
-    operations = [
-        migrations.CreateModel(
-            name='LayerRNDT',
-            fields=[
-                ('id', models.AutoField(auto_created=True, primary_key=True, serialize=False, verbose_name='ID')),
-                ('constraints_other', models.TextField(default=None, null=True)),
-                ('layer', models.OneToOneField(on_delete=django.db.models.deletion.CASCADE, to=fk_pointed_class)),
-            ],
-            options={
-                'verbose_name_plural': 'Layer RNDT',
-                'ordering': ('layer', 'constraints_other'),
-            },
-        ),
-    ]

rndt/migrations/0004_layerrndt_resolution.py

@@ -1,18 +1,36 @@
 # Generated by Django 2.2.16 on 2021-02-24 18:05
+import logging
 
 from django.db import migrations, models
 
+logger = logging.getLogger(__name__)
 
-class Migration(migrations.Migration):
+try:
+    from geonode.layers.models import Layer
+    logger.error("Linking LayerRNDT to Layer (<4.x) -- we're not supposed to be here!")
+    class Migration(migrations.Migration):
 
-    dependencies = [
-        ('rndt', '0003_layerrndt'),
-    ]
+        dependencies = [
+            ('rndt', '0003_layerrndt'),
+        ]
+
+        operations = [
+            migrations.AddField(
+                model_name='layerrndt',
+                name='resolution',
+                field=models.FloatField(default=None, null=True),
+            ),
+        ]
+except ImportError:
+    try:
+        from geonode.layers.models import Dataset
+        logger.debug("Deferring LayerRNDT creation on geonode>=4.x)")
+        # when running on 4.x, we're going to deal with the RNDTLayer model in a brand new migration (0006)
+
+        class Migration(migrations.Migration):
+            dependencies = [('rndt', '0003_layerrndt'),]
+            operations = [migrations.RunPython(migrations.RunPython.noop, migrations.RunPython.noop)]
+
+    except ImportError:
+        raise Exception('Can not find base class for LayerRNDT')
 
-    operations = [
-        migrations.AddField(
-            model_name='layerrndt',
-            name='resolution',
-            field=models.FloatField(default=None, null=True),
-        ),
-    ]

rndt/migrations/0005_layerrndt_accuracy.py

@@ -1,18 +1,38 @@
 # Generated by Django 2.2.16 on 2021-02-25 16:27
+import logging
 
 from django.db import migrations, models
 
+logger = logging.getLogger(__name__)
 
-class Migration(migrations.Migration):
+try:
+    from geonode.layers.models import Layer
+    logger.error("Linking LayerRNDT to Layer (<4.x) -- we're not supposed to be here!")
 
-    dependencies = [
-        ('rndt', '0004_layerrndt_resolution'),
-    ]
+    class Migration(migrations.Migration):
+
+        dependencies = [
+            ('rndt', '0004_layerrndt_resolution'),
+        ]
+
+        operations = [
+            migrations.AddField(
+                model_name='layerrndt',
+                name='accuracy',
+                field=models.FloatField(default=None, null=True),
+            ),
+        ]
+
+except ImportError:
+    try:
+        from geonode.layers.models import Dataset
+        logger.debug("Deferring LayerRNDT creation on geonode>=4.x)")
+        # when running on 4.x, we're going to deal with the RNDTLayer model in a brand new migration (0006)
+
+        class Migration(migrations.Migration):
+            dependencies = [('rndt', '0004_layerrndt_resolution'),]
+            operations = [migrations.RunPython(migrations.RunPython.noop, migrations.RunPython.noop)]
+
+    except ImportError:
+        raise Exception('Can not find base class for LayerRNDT')
 
-    operations = [
-        migrations.AddField(
-            model_name='layerrndt',
-            name='accuracy',
-            field=models.FloatField(default=None, null=True),
-        ),
-    ]

rndt/migrations/0006_layerrndt.py

@@ -0,0 +1,51 @@
+# Generated by Django 3.2.16 on 2023-03-07 14:58
+
+from django.db import migrations, models, connection
+import django.db.models.deletion
+
+# common model operation
+create_model_operation = migrations.CreateModel(
+    name='LayerRNDT',
+    fields=[
+        ('id', models.AutoField(auto_created=True, primary_key=True, serialize=False, verbose_name='ID')),
+        ('constraints_other', models.TextField(default=None, null=True)),
+        ('resolution', models.FloatField(default=None, null=True)),
+        ('accuracy', models.FloatField(default=None, null=True)),
+        ('layer', models.OneToOneField(on_delete=django.db.models.deletion.CASCADE, to='layers.dataset')),
+    ],
+    options={
+        'verbose_name_plural': 'Layer RNDT',
+        'ordering': ('layer', 'constraints_other'),
+    },
+)
+
+# We're going to deal with both
+# - MIGRATION from 3.3
+#   - we already have the table in the DB,
+#   - we modified the previous migration in order to have noop operations for each RNDT migration, so we'll have to deal
+#     with the model stuff here
+#   - the db change is only related to a FK table (was layers_layer, become layers_dataset), but this change in db
+#     is automatically performed by the DBMS once the table is renamed (migration '0038_rename_layer_dataset').
+# - CREATION in 4.x
+#   - we are going to deal with both db and django state here
+
+if 'rndt_layerrndt' not in connection.introspection.table_names():
+    # we don't have the table in the DB: let's have a complete (state+db) Model
+    ops = [create_model_operation, ]
+else:
+    # we do have the table in the DB, so we need to synch the Model state only
+    ops = [
+        migrations.SeparateDatabaseAndState(
+            state_operations=[create_model_operation, ],
+            database_operations=[]
+        )
+    ]
+
+
+class Migration(migrations.Migration):
+    dependencies = [
+        ('layers', '0038_rename_layer_dataset'),
+        ('rndt', '0005_layerrndt_accuracy'),
+    ]
+
+    operations = ops

rndt/migrations/__init__.py

@@ -0,0 +1,26 @@
+import logging
+
+from django.db import DatabaseError, connections
+from django.db.migrations.recorder import MigrationRecorder
+
+logger = logging.getLogger(__name__)
+
+
+def migration_applied(app_label: str, migration_name: str) -> bool:
+
+    for alias in connections:
+        try:
+            if (
+                MigrationRecorder.Migration.objects.using(alias)
+                .filter(app=app_label, name=migration_name)
+                .exists()
+            ):
+                logger.info("MIGRATION EXIST")
+                return True
+        except DatabaseError as e:
+            # django_migrations table does not exist -> no migrations applied
+            logger.info("ERROR RETRIEVING MIGRATIONS ", exc_info=e)
+            pass
+
+    logger.info("MIGRATION DOES NOT EXIST")
+    return False