Consumer Api: Deleting an identity with an already decomposed relatio…

…nship throws an error (#977)

* fix: Don't throw an error if the relationship is already decomposed

* chore: Remove unnecessary test

Modules/Relationships/src/Relationships.Domain/Aggregates/Relationships/Relationship.DecomposeDueToIdentityDeletionTests.cs

@@ -30,19 +30,6 @@ public void Decomposition_can_be_performed_from_multiple_statuses(RelationshipSt
         relationship.ToHasDecomposed.Should().BeFalse();
     }
 
-    [Fact]
-    public void Decomposition_can_not_be_called_by_the_same_identity_twice()
-    {
-        // Arrange
-        var relationship = CreateRelationshipDecomposedByFrom(IDENTITY_1, IDENTITY_2);
-
-        // Act
-        var acting = () => relationship.DecomposeDueToIdentityDeletion(IDENTITY_1, DID_DOMAIN_NAME);
-
-        // Assert
-        acting.Should().Throw<DomainException>().WithError("error.platform.validation.relationship.relationshipAlreadyDecomposed");
-    }
-
     [Fact]
     public void Decomposition_can_not_be_performed_by_other_identities()
     {

Modules/Relationships/src/Relationships.Domain/Aggregates/Relationships/Relationship.cs

@@ -306,7 +306,8 @@ public void Decompose(IdentityAddress activeIdentity, DeviceId activeDevice)
     public void DecomposeDueToIdentityDeletion(IdentityAddress identityToBeDeleted, string didDomainName)
     {
         EnsureHasParticipant(identityToBeDeleted);
-        EnsureRelationshipNotDecomposedBy(identityToBeDeleted);
+
+        if (From == identityToBeDeleted && FromHasDecomposed || To == identityToBeDeleted && ToHasDecomposed) return;
 
         if (Status is RelationshipStatus.DeletionProposed)
             DecomposeAsSecondParticipant(identityToBeDeleted, null, RelationshipAuditLogEntryReason.DecompositionDueToIdentityDeletion);