Add additional "reason" field to CreditRequirementStatus

* Add "reason" JSON-encoded field to CreditRequirementStatus.
* Add a "failed" status to CreditRequirementStatus.status choices.

openedx/core/djangoapps/credit/migrations/0003_add_creditrequirementstatus_reason.py

+# -*- coding: utf-8 -*-
+from south.utils import datetime_utils as datetime
+from south.db import db
+from south.v2 import SchemaMigration
+from django.db import models
+
+
+class Migration(SchemaMigration):
+
+    def forwards(self, orm):
+        # Adding field 'CreditRequirementStatus.reason'
+        db.add_column('credit_creditrequirementstatus', 'reason',
+                      self.gf('jsonfield.fields.JSONField')(default={}),
+                      keep_default=False)
+
+
+    def backwards(self, orm):
+        # Deleting field 'CreditRequirementStatus.reason'
+        db.delete_column('credit_creditrequirementstatus', 'reason')
+
+
+    models = {
+        'credit.creditcourse': {
+            'Meta': {'object_name': 'CreditCourse'},
+            'course_key': ('xmodule_django.models.CourseKeyField', [], {'unique': 'True', 'max_length': '255', 'db_index': 'True'}),
+            'enabled': ('django.db.models.fields.BooleanField', [], {'default': 'False'}),
+            'id': ('django.db.models.fields.AutoField', [], {'primary_key': 'True'})
+        },
+        'credit.crediteligibility': {
+            'Meta': {'unique_together': "(('username', 'course'),)", 'object_name': 'CreditEligibility'},
+            'course': ('django.db.models.fields.related.ForeignKey', [], {'related_name': "'eligibilities'", 'to': "orm['credit.CreditCourse']"}),
+            'created': ('model_utils.fields.AutoCreatedField', [], {'default': 'datetime.datetime.now'}),
+            'id': ('django.db.models.fields.AutoField', [], {'primary_key': 'True'}),
+            'modified': ('model_utils.fields.AutoLastModifiedField', [], {'default': 'datetime.datetime.now'}),
+            'provider': ('django.db.models.fields.related.ForeignKey', [], {'related_name': "'eligibilities'", 'to': "orm['credit.CreditProvider']"}),
+            'username': ('django.db.models.fields.CharField', [], {'max_length': '255', 'db_index': 'True'})
+        },
+        'credit.creditprovider': {
+            'Meta': {'object_name': 'CreditProvider'},
+            'created': ('model_utils.fields.AutoCreatedField', [], {'default': 'datetime.datetime.now'}),
+            'display_name': ('django.db.models.fields.CharField', [], {'max_length': '255'}),
+            'id': ('django.db.models.fields.AutoField', [], {'primary_key': 'True'}),
+            'modified': ('model_utils.fields.AutoLastModifiedField', [], {'default': 'datetime.datetime.now'}),
+            'provider_id': ('django.db.models.fields.CharField', [], {'unique': 'True', 'max_length': '255', 'db_index': 'True'})
+        },
+        'credit.creditrequirement': {
+            'Meta': {'unique_together': "(('namespace', 'name', 'course'),)", 'object_name': 'CreditRequirement'},
+            'active': ('django.db.models.fields.BooleanField', [], {'default': 'True'}),
+            'course': ('django.db.models.fields.related.ForeignKey', [], {'related_name': "'credit_requirements'", 'to': "orm['credit.CreditCourse']"}),
+            'created': ('model_utils.fields.AutoCreatedField', [], {'default': 'datetime.datetime.now'}),
+            'criteria': ('jsonfield.fields.JSONField', [], {}),
+            'id': ('django.db.models.fields.AutoField', [], {'primary_key': 'True'}),
+            'modified': ('model_utils.fields.AutoLastModifiedField', [], {'default': 'datetime.datetime.now'}),
+            'name': ('django.db.models.fields.CharField', [], {'max_length': '255'}),
+            'namespace': ('django.db.models.fields.CharField', [], {'max_length': '255'})
+        },
+        'credit.creditrequirementstatus': {
+            'Meta': {'object_name': 'CreditRequirementStatus'},
+            'created': ('model_utils.fields.AutoCreatedField', [], {'default': 'datetime.datetime.now'}),
+            'id': ('django.db.models.fields.AutoField', [], {'primary_key': 'True'}),
+            'modified': ('model_utils.fields.AutoLastModifiedField', [], {'default': 'datetime.datetime.now'}),
+            'reason': ('jsonfield.fields.JSONField', [], {'default': '{}'}),
+            'requirement': ('django.db.models.fields.related.ForeignKey', [], {'related_name': "'statuses'", 'to': "orm['credit.CreditRequirement']"}),
+            'status': ('django.db.models.fields.CharField', [], {'max_length': '32'}),
+            'username': ('django.db.models.fields.CharField', [], {'max_length': '255', 'db_index': 'True'})
+        }
+    }
+
+    complete_apps = ['credit']
\ No newline at end of file

openedx/core/djangoapps/credit/models.py

@@ -135,16 +135,36 @@ class CreditRequirement(TimeStampedModel):
 
 
 class CreditRequirementStatus(TimeStampedModel):
-    """This model represents the status of each requirement."""
+    """This model represents the status of each requirement.
+
+    For a particular credit requirement, a user can either:
+    1) Have satisfied the requirement (example: approved in-course reverification)
+    2) Have failed the requirement (example: denied in-course reverification)
+    3) Neither satisfied nor failed (example: the user hasn't yet attempted in-course reverification).
+
+    Cases (1) and (2) are represented by having a CreditRequirementStatus with
+    the status set to "satisfied" or "failed", respectively.
+
+    In case (3), no CreditRequirementStatus record will exist for the requirement and user.
+
+    """
 
     REQUIREMENT_STATUS_CHOICES = (
         ("satisfied", "satisfied"),
+        ("failed", "failed"),
     )
 
     username = models.CharField(max_length=255, db_index=True)
     requirement = models.ForeignKey(CreditRequirement, related_name="statuses")
     status = models.CharField(choices=REQUIREMENT_STATUS_CHOICES, max_length=32)
 
+    # Include additional information about why the user satisfied or failed
+    # the requirement.  This is specific to the type of requirement.
+    # For example, the minimum grade requirement might record the user's
+    # final grade when the user completes the course.  This allows us to display
+    # the grade to users later and to send the information to credit providers.
+    reason = JSONField(default={})
+
 
 class CreditEligibility(TimeStampedModel):
     """A record of a user's eligibility for credit from a specific credit