add support for calculating CVSS

Signed-off-by: Ziad <ziadhany2016@gmail.com>

Author: ziadhany

vulnerabilities/models.py

@@ -367,15 +367,27 @@ class VulnerabilitySeverity(models.Model):
         ),
     )
 
-    value = models.CharField(max_length=50, help_text="Example: 9.0, Important, High")
+    value = models.CharField(
+        max_length=50,
+        help_text="Score Value expressed as a number such as 9.0 that can be sorted or compared",
+    )
 
-    @property
-    def scoring_element(self):
-        try:
-            score = SCORING_SYSTEMS[self.scoring_system].as_score(self.value)
-            return score
-        except NotImplementedError:
-            return
+    scoring_elements = models.CharField(
+        max_length=100,
+        null=True,
+        help_text="Supporting a scoring elements as a string "
+        "For example a CVSS vector Important, High, Medium ,Low."
+        "Typically used to compute the value",
+    )
+
+    def save(self, *args, **kwargs):
+        super().save(*args, **kwargs)
+        if not self.value and self.scoring_elements:
+            try:
+                self.value = SCORING_SYSTEMS[self.scoring_system].as_score(self.value)
+                super().save(update_fields=["value"])
+            except NotImplementedError:
+                pass
 
     class Meta:
         unique_together = ["reference", "scoring_system", "value"]