Stub new method for application datastore

Handle command failures more gracefully than continuously retrying. Failures are not logged
Add table for certificates.

applications/datastore.go

@@ -44,6 +44,10 @@ func NewDB(driver, conn string, logger kitlog.Logger) (Datastore, error) {
 	}
 }
 
+func (store pgStore) New(src string, a *Application) (string, error) {
+	return "", nil
+}
+
 func (store pgStore) GetApplicationsByDeviceUUID(deviceUUID string) (*[]Application, error) {
 	apps := []Application{}
 	query := `SELECT * FROM applications

connect/endpoint.go

@@ -55,6 +55,20 @@ func makeConnectEndpoint(svc Service) endpoint.Endpoint {
 				return mdmConnectResponse{}, nil
 			}
 			return mdmConnectResponse{payload: next}, nil
+		case "Error":
+			total, err := svc.FailCommand(ctx, req.Response)
+			if err != nil {
+				return mdmConnectResponse{Err: err}, nil
+			}
+			// TODO: Deal with command failures
+			if total != 0 {
+				next, _, err := svc.NextCommand(ctx, req.Response)
+				if err != nil {
+					return mdmConnectResponse{Err: err}, nil
+				}
+				return mdmConnectResponse{payload: next}, nil
+			}
+
 		default:
 			return mdmConnectResponse{Err: errInvalidMessageType}, nil
 		}

connect/service.go

@@ -12,6 +12,7 @@ import (
 type Service interface {
 	Acknowledge(ctx context.Context, req mdm.Response) (int, error)
 	NextCommand(ctx context.Context, req mdm.Response) ([]byte, int, error)
+	FailCommand(ctx context.Context, req mdm.Response) (int, error)
 
 	RegisterAckHandler(requestType string, handler func(req mdm.Response, datastores map[string]interface{}) error, datastores map[string]interface{})
 	FindAckHandler(requestType string) (func(req mdm.Response) error, bool)
@@ -66,6 +67,10 @@ func (svc service) NextCommand(ctx context.Context, req mdm.Response) ([]byte, i
 	return svc.commands.NextCommand(req.UDID)
 }
 
+func (svc service) FailCommand(ctx context.Context, req mdm.Response) (int, error) {
+	return svc.commands.DeleteCommand(req.UDID, req.CommandUUID)
+}
+
 func (svc service) checkRequeue(deviceUDID string) (int, error) {
 	existing, err := svc.devices.GetDeviceByUDID(deviceUDID, []string{"awaiting_configuration"}...)
 	if err != nil {
@@ -85,6 +90,7 @@ func (svc service) checkRequeue(deviceUDID string) (int, error) {
 	return 0, nil
 }
 
+// Register a handler function for a given RequestType, include datastore dependencies as a map.
 func (svc service) RegisterAckHandler(requestType string, handler func(req mdm.Response, datastores map[string]interface{}) error, datastores map[string]interface{}) {
 	datastoreInjectedHandler := func(req mdm.Response) error {
 		return handler(req, datastores)
@@ -92,7 +98,7 @@ func (svc service) RegisterAckHandler(requestType string, handler func(req mdm.R
 	svc.handlers = append(svc.handlers, ackHandler{requestType, datastoreInjectedHandler})
 }
 
-// If not found, second return variable is false
+// Find a handler function which is registered to deal with the RequestType
 func (svc service) FindAckHandler(requestType string) (func(req mdm.Response) error, bool) {
 	for _, h := range svc.handlers {
 		if h.requestType == requestType {
@@ -103,6 +109,7 @@ func (svc service) FindAckHandler(requestType string) (func(req mdm.Response) er
 	return nil, false
 }
 
+// Execute any registered handler function which matches the given RequestType
 func (svc service) ExecAckHandler(requestType string, req mdm.Response) error {
 	handler, found := svc.FindAckHandler(requestType)
 	if !found {

migrations/201607110002_certificates_down.sql

@@ -0,0 +1 @@
+DROP TABLE IF EXISTS certificates;

migrations/201607110002_certificates_up.sql

@@ -0,0 +1,9 @@
+CREATE EXTENSION IF NOT EXISTS "uuid-ossp";
+
+CREATE TABLE IF NOT EXISTS certificates (
+  certificate_uuid uuid PRIMARY KEY DEFAULT uuid_generate_v4(),
+  common_name text NOT NULL,
+  data BYTEA NOT NULL,
+  is_identity BOOL DEFAULT false
+)
+