Add support for external contracts for ACI

Author: Satish Ramachandran

netmaster/objApi/apiController.go

@@ -343,10 +343,10 @@ func endpointGroupCleanup(endpointGroup *contivModel.EndpointGroup) {
 		policy.Write()
 	}
 
-    // Cleanup any external contracts
+	// Cleanup any external contracts
 	err = extContracts.CleanupExternalContracts(endpointGroup)
 	if err != nil {
-		return err
+		log.Errorf("Error cleaning up external contracts for epg %s", endpointGroup.Key)
 	}
 
 	// Remove the endpoint group from network and tenant link sets.
@@ -397,12 +397,6 @@ func (ac *APIController) EndpointGroupCreate(endpointGroup *contivModel.Endpoint
 		return err
 	}
 
-	// Setup external contracts this EPG might have.
-	err = extContracts.SetupExternalContracts(endpointGroup, endpointGroup.ConsExtContractsGrps, endpointGroup.ProvExtContractsGrps)
-	if err != nil {
-		return err
-	}
-
 	// for each policy create an epg policy Instance
 	for _, policyName := range endpointGroup.Policies {
 		policyKey := endpointGroup.TenantName + ":" + policyName
@@ -434,6 +428,14 @@ func (ac *APIController) EndpointGroupCreate(endpointGroup *contivModel.Endpoint
 		}
 	}
 
+	// Setup external contracts this EPG might have.
+	err = extContracts.SetupExternalContracts(endpointGroup, endpointGroup.ConsExtContractsGrps, endpointGroup.ProvExtContractsGrps)
+	if err != nil {
+		log.Errorf("Error setting up external contracts for epg %s", endpointGroup.Key)
+		endpointGroupCleanup(endpointGroup)
+		return err
+	}
+
 	// Setup links
 	modeldb.AddLink(&endpointGroup.Links.Network, network)
 	modeldb.AddLink(&endpointGroup.Links.Tenant, tenant)
@@ -1194,7 +1196,7 @@ func (ac *APIController) ExtContractsGroupDelete(contractsGroup *contivModel.Ext
 
 	// At this moment, we let the external contracts to be deleted only
 	// if there are no consumers of this external contracts group
-	if isExtContractsGroupUsed(contractsGroup) == true {
+	if extContracts.IsExtContractsGroupUsed(contractsGroup) == true {
 		log.Errorf("Error: External contracts groups is being used: %s", contractsGroup.ContractsGroupName)
 		return core.Errorf("External contracts group is in-use")
 	}

utils/extContracts/extContracts.go

@@ -92,7 +92,10 @@ func CleanupExternalContracts(endpointGroup *contivModel.EndpointGroup) error {
 		contractsGrp := contivModel.FindExtContractsGroup(consExtContractsGrp)
 		err := extContractsGrpDeregister(endpointGroup, contractsGrp, "consumed")
 		if err != nil {
-			return err
+			if contractsGrp != nil {
+				log.Errorf("Error cleaning up consumed ext contract %s", contractsGrp.ContractsGroupName)
+			}
+			continue
 		}
 	}
 
@@ -101,7 +104,10 @@ func CleanupExternalContracts(endpointGroup *contivModel.EndpointGroup) error {
 		contractsGrp := contivModel.FindExtContractsGroup(provExtContractsGrp)
 		err := extContractsGrpDeregister(endpointGroup, contractsGrp, "provided")
 		if err != nil {
-			return err
+			if contractsGrp != nil {
+				log.Errorf("Error cleaning up provided ext contract %s", contractsGrp.ContractsGroupName)
+			}
+			continue
 		}
 	}
 
@@ -131,3 +137,12 @@ func SetupExternalContracts(endpointGroup *contivModel.EndpointGroup,
 
 	return nil
 }
+
+// Check if the external contracts are being used by any of the EPGs.
+func IsExtContractsGroupUsed(contractsGroup *contivModel.ExtContractsGroup) bool {
+	if len(contractsGroup.LinkSets.EndpointGroups) > 0 {
+		return true
+	}
+
+	return false
+}