Introduce item levels

eap_backend/eap_api/migrations/0011_auto_20220405_1609.py

@@ -0,0 +1,91 @@
+# Generated by Django 3.2.8 on 2022-04-05 16:09
+
+from django.db import migrations, models
+import django.db.models.deletion
+import django.utils.timezone
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ("eap_api", "0010_merge_0009_auto_20211110_1654_0009_auto_20211115_1615"),
+    ]
+
+    operations = [
+        migrations.AddField(
+            model_name="argument",
+            name="created_date",
+            field=models.DateTimeField(
+                auto_now_add=True, default=django.utils.timezone.now
+            ),
+            preserve_default=False,
+        ),
+        migrations.AddField(
+            model_name="evidence",
+            name="created_date",
+            field=models.DateTimeField(
+                auto_now_add=True, default=django.utils.timezone.now
+            ),
+            preserve_default=False,
+        ),
+        migrations.AddField(
+            model_name="evidentialclaim",
+            name="created_date",
+            field=models.DateTimeField(
+                auto_now_add=True, default=django.utils.timezone.now
+            ),
+            preserve_default=False,
+        ),
+        migrations.AddField(
+            model_name="propertyclaim",
+            name="created_date",
+            field=models.DateTimeField(
+                auto_now_add=True, default=django.utils.timezone.now
+            ),
+            preserve_default=False,
+        ),
+        migrations.AddField(
+            model_name="propertyclaim",
+            name="level",
+            field=models.PositiveIntegerField(default=1),
+            preserve_default=False,
+        ),
+        migrations.AddField(
+            model_name="propertyclaim",
+            name="property_claim",
+            field=models.ForeignKey(
+                blank=True,
+                null=True,
+                on_delete=django.db.models.deletion.CASCADE,
+                related_name="property_claims",
+                to="eap_api.propertyclaim",
+            ),
+        ),
+        migrations.AddField(
+            model_name="systemdescription",
+            name="created_date",
+            field=models.DateTimeField(
+                auto_now_add=True, default=django.utils.timezone.now
+            ),
+            preserve_default=False,
+        ),
+        migrations.AddField(
+            model_name="toplevelnormativegoal",
+            name="created_date",
+            field=models.DateTimeField(
+                auto_now_add=True, default=django.utils.timezone.now
+            ),
+            preserve_default=False,
+        ),
+        migrations.AlterField(
+            model_name="propertyclaim",
+            name="goal",
+            field=models.ForeignKey(
+                blank=True,
+                null=True,
+                on_delete=django.db.models.deletion.CASCADE,
+                related_name="property_claims",
+                to="eap_api.toplevelnormativegoal",
+            ),
+        ),
+    ]

eap_backend/eap_api/models.py

@@ -18,6 +18,23 @@ class Shape(Enum):
     CYLINDER = 3
 
 
+class CaseItem(models.Model):
+    """A class that all the assurance case items inherit from.
+
+    CaseItem is an abstract base class, meaning that it's not meant to have its own
+    table.
+    """
+
+    name = models.CharField(max_length=200)
+    short_description = models.CharField(max_length=1000)
+    long_description = models.CharField(max_length=3000)
+    shape = Shape
+    created_date = models.DateTimeField(auto_now_add=True)
+
+    class Meta:
+        abstract = True
+
+
 class AssuranceCase(models.Model):
     name = models.CharField(max_length=200)
     description = models.CharField(max_length=1000)
@@ -31,10 +48,7 @@ def was_published_recently(self):
         return self.created_date >= timezone.now() - datetime.timedelta(days=1)
 
 
-class TopLevelNormativeGoal(models.Model):
-    name = models.CharField(max_length=200)
-    short_description = models.CharField(max_length=1000)
-    long_description = models.CharField(max_length=3000)
+class TopLevelNormativeGoal(CaseItem):
     keywords = models.CharField(max_length=3000)
     assurance_case = models.ForeignKey(
         AssuranceCase, related_name="goals", on_delete=models.CASCADE
@@ -45,21 +59,14 @@ def __str__(self):
         return self.name
 
 
-class Context(models.Model):
-    name = models.CharField(max_length=200)
-    short_description = models.CharField(max_length=1000)
-    long_description = models.CharField(max_length=3000)
+class Context(CaseItem):
     shape = Shape.DIAMOND
-    created_date = models.DateTimeField(auto_now_add=True)
     goal = models.ForeignKey(
         TopLevelNormativeGoal, related_name="context", on_delete=models.CASCADE
     )
 
 
-class SystemDescription(models.Model):
-    name = models.CharField(max_length=200)
-    short_description = models.CharField(max_length=1000)
-    long_description = models.CharField(max_length=3000)
+class SystemDescription(CaseItem):
     shape = Shape.DIAMOND
     goal = models.ForeignKey(
         TopLevelNormativeGoal,
@@ -68,38 +75,55 @@ class SystemDescription(models.Model):
     )
 
 
-class PropertyClaim(models.Model):
-    name = models.CharField(max_length=200)
-    short_description = models.CharField(max_length=1000)
-    long_description = models.CharField(max_length=3000)
+class PropertyClaim(CaseItem):
     shape = Shape.ROUNDED_RECTANGLE
     goal = models.ForeignKey(
-        TopLevelNormativeGoal, related_name="property_claims", on_delete=models.CASCADE
+        TopLevelNormativeGoal,
+        null=True,
+        blank=True,
+        related_name="property_claims",
+        on_delete=models.CASCADE,
     )
-
-
-class Argument(models.Model):
-    name = models.CharField(max_length=200)
-    short_description = models.CharField(max_length=1000)
-    long_description = models.CharField(max_length=3000)
+    property_claim = models.ForeignKey(
+        "self",
+        null=True,
+        blank=True,
+        related_name="property_claims",
+        on_delete=models.CASCADE,
+    )
+    level = models.PositiveIntegerField()
+
+    def save(self, *args, **kwargs):
+        try:
+            parent_level = self.parent.level
+        except AttributeError:
+            # If the parent is a TopLevelNormativeGoal rather than a PropertyClaim, it
+            # doesn't have a level.
+            parent_level = 0
+        self.level = parent_level + 1
+        # TODO Is this the right place to assert these things?
+        has_goal_parent = bool(self.goal)
+        has_claim_parent = bool(self.property_claim)
+        if has_claim_parent and has_goal_parent:
+            raise ValueError("A PropertyClaim shouldn't have two parents.")
+        if not (has_claim_parent or has_goal_parent):
+            raise ValueError("A PropertyClaim should have a parent.")
+        super().save(*args, **kwargs)
+
+
+class Argument(CaseItem):
     shape = Shape.ROUNDED_RECTANGLE
     property_claim = models.ManyToManyField(PropertyClaim, related_name="arguments")
 
 
-class EvidentialClaim(models.Model):
-    name = models.CharField(max_length=200)
-    short_description = models.CharField(max_length=1000)
-    long_description = models.CharField(max_length=3000)
+class EvidentialClaim(CaseItem):
     shape = Shape.ROUNDED_RECTANGLE
     argument = models.ForeignKey(
         Argument, related_name="evidential_claims", on_delete=models.CASCADE
     )
 
 
-class Evidence(models.Model):
-    name = models.CharField(max_length=200)
-    short_description = models.CharField(max_length=1000)
-    long_description = models.CharField(max_length=3000)
+class Evidence(CaseItem):
     URL = models.CharField(max_length=3000)
     shape = Shape.CYLINDER
     evidential_claim = models.ManyToManyField(EvidentialClaim, related_name="evidence")

eap_backend/eap_api/serializers.py

@@ -71,9 +71,20 @@ class Meta:
 
 class PropertyClaimSerializer(serializers.ModelSerializer):
     goal_id = serializers.PrimaryKeyRelatedField(
-        source="goal", queryset=TopLevelNormativeGoal.objects.all(), write_only=True
+        source="goal",
+        queryset=TopLevelNormativeGoal.objects.all(),
+        write_only=True,
+        required=False,
+    )
+    property_claim_id = serializers.PrimaryKeyRelatedField(
+        source="property_claim",
+        queryset=PropertyClaim.objects.all(),
+        write_only=True,
+        required=False,
     )
+    level = serializers.IntegerField(read_only=True)
     arguments = serializers.PrimaryKeyRelatedField(many=True, read_only=True)
+    property_claims = serializers.PrimaryKeyRelatedField(many=True, read_only=True)
 
     class Meta:
         model = PropertyClaim
@@ -83,7 +94,10 @@ class Meta:
             "short_description",
             "long_description",
             "goal_id",
+            "property_claim_id",
+            "level",
             "arguments",
+            "property_claims",
         )
 
 

eap_backend/eap_api/views.py

@@ -35,49 +35,49 @@
         "model": TopLevelNormativeGoal,
         "children": ["context", "system_description", "property_claims"],
         "fields": ("name", "short_description", "long_description", "keywords"),
-        "parent_type": ("assurance_case", False),
+        "parent_types": [("assurance_case", False)],
     },
     "context": {
         "serializer": ContextSerializer,
         "model": Context,
         "children": [],
         "fields": ("name", "short_description", "long_description"),
-        "parent_type": ("goal", False),
+        "parent_types": [("goal", False)],
     },
     "system_description": {
         "serializer": SystemDescriptionSerializer,
         "model": SystemDescription,
         "children": [],
         "fields": ("name", "short_description", "long_description"),
-        "parent_type": ("goal", False),
+        "parent_types": [("goal", False)],
     },
     "property_claims": {
         "serializer": PropertyClaimSerializer,
         "model": PropertyClaim,
-        "children": ["arguments"],
+        "children": ["arguments", "property_claims"],
         "fields": ("name", "short_description", "long_description"),
-        "parent_type": ("goal", False),
+        "parent_types": [("goal", False), ("property_claim", False)],
     },
     "arguments": {
         "serializer": ArgumentSerializer,
         "model": Argument,
         "children": ["evidential_claims"],
         "fields": ("name", "short_description", "long_description"),
-        "parent_type": ("property_claim", True),
+        "parent_types": [("property_claim", True)],
     },
     "evidential_claims": {
         "serializer": EvidentialClaimSerializer,
         "model": EvidentialClaim,
         "children": ["evidence"],
         "fields": ("name", "short_description", "long_description"),
-        "parent_type": ("argument", False),
+        "parent_types": [("argument", False)],
     },
     "evidence": {
         "serializer": EvidenceSerializer,
         "model": Evidence,
         "children": [],
         "fields": ("name", "short_description", "long_description", "URL"),
-        "parent_type": ("evidential_claim", True),
+        "parent_types": [("evidential_claim", True)],
     },
 }
 
@@ -145,7 +145,7 @@ def get_json_tree(id_list, obj_type):
     return objs
 
 
-def save_json_tree(data, obj_type, parent_id=None):
+def save_json_tree(data, obj_type, parent_id=None, parent_type=None):
     """Recursively write items in an assurance case tree.
 
     Create a new assurance case like the one described by data, including all
@@ -167,11 +167,15 @@ def save_json_tree(data, obj_type, parent_id=None):
     # so that e.g. the new object gets a unique ID even if `data` specifies an
     # ID.
     this_data = {k: data[k] for k in TYPE_DICT[obj_type]["fields"]}
-    if parent_id is not None:
-        parent_type, plural = TYPE_DICT[obj_type]["parent_type"]
-        if plural:
-            parent_id = [parent_id]
-        this_data[parent_type + "_id"] = parent_id
+    if parent_id is not None and parent_type is not None:
+        for parent_type_tmp, plural in TYPE_DICT[obj_type]["parent_types"]:
+            # TODO This is silly. It's all because some parent_type names are written
+            # with a plural s in the end while others are not.
+            if parent_type not in parent_type_tmp:
+                continue
+            if plural:
+                parent_id = [parent_id]
+            this_data[parent_type_tmp + "_id"] = parent_id
     serializer_class = TYPE_DICT[obj_type]["serializer"]
     serializer = serializer_class(data=this_data)
     if serializer.is_valid():
@@ -188,7 +192,9 @@ def save_json_tree(data, obj_type, parent_id=None):
         if child_type not in data:
             continue
         for child_data in data[child_type]:
-            retval = save_json_tree(child_data, child_type, parent_id=id)
+            retval = save_json_tree(
+                child_data, child_type, parent_id=id, parent_type=obj_type
+            )
             # If one of the subcalls returns an error, return.
             if retval.status_code != success_http_code:
                 return retval