Sketch out an interface for generators.

.gitignore

@@ -7,6 +7,7 @@
 *.dylib
 bin
 vendor
+dist
 
 # Test binary, build with `go test -c`
 *.test

go.mod

@@ -15,6 +15,7 @@ require (
 	github.com/kballard/go-shellquote v0.0.0-20180428030007-95032a82bc51 // indirect
 	github.com/pkg/errors v0.9.1 // indirect
 	github.com/sergi/go-diff v1.1.0 // indirect
+	github.com/sirupsen/logrus v1.4.2
 	github.com/yudai/gojsondiff v1.0.1-0.20180504020246-0525c875b75c // indirect
 	github.com/yudai/golcs v0.0.0-20170316035057-ecda9a501e82 // indirect
 	github.com/yudai/pp v2.0.1+incompatible // indirect

pkg/controllers/applicationset_controller.go

@@ -31,7 +31,7 @@ import (
 // ApplicationSetReconciler reconciles a ApplicationSet object
 type ApplicationSetReconciler struct {
 	client.Client
-	Scheme *runtime.Scheme
+	Scheme   *runtime.Scheme
 	Recorder record.EventRecorder
 }
 
@@ -42,8 +42,8 @@ func (r *ApplicationSetReconciler) Reconcile(req ctrl.Request) (ctrl.Result, err
 	ctx := context.Background()
 	_ = log.WithField("applicationset", req.NamespacedName)
 
-	var applicationSetInfo argoprojiov1alpha1.ApplicationSet
-	if err := r.Get(ctx, req.NamespacedName, &applicationSetInfo); err != nil {
+	var appSet argoprojiov1alpha1.ApplicationSet
+	if err := r.Get(ctx, req.NamespacedName, &appSet); err != nil {
 		log.Info("Unable to fetch applicationSetInfo %v", err)
 
 		return ctrl.Result{}, client.IgnoreNotFound(err)

pkg/generators/cluster.go

@@ -0,0 +1,30 @@
+package generators
+
+import (
+	"fmt"
+	argoprojiov1alpha1 "github.com/argoproj-labs/applicationset/api/v1alpha1"
+	argov1alpha1 "github.com/argoproj/argo-cd/pkg/apis/application/v1alpha1"
+	"sigs.k8s.io/controller-runtime/pkg/client"
+)
+
+var _ Generator = (*ClusterGenerator)(nil)
+
+// ClusterGenerator generates Applications for some or all clusters registered with ArgoCD.
+type ClusterGenerator struct {
+	commonClient client.Client
+}
+
+func NewClusterGenerator(client client.Client) Generator {
+	g := &ClusterGenerator{
+		commonClient: client,
+	}
+	return g
+}
+
+func (g *ClusterGenerator) GenerateApplications(appSet *argoprojiov1alpha1.ApplicationSet) ([]argov1alpha1.Application, error) {
+	if appSet == nil {
+		return nil, fmt.Errorf("ApplicationSet is empty ")
+	}
+
+	return nil, nil
+}

pkg/generators/interface.go

@@ -0,0 +1,14 @@
+package generators
+
+import (
+	argoprojiov1alpha1 "github.com/argoproj-labs/applicationset/api/v1alpha1"
+	argov1alpha1 "github.com/argoproj/argo-cd/pkg/apis/application/v1alpha1"
+)
+
+// Generator defines the interface implemented by all ApplicationSet generators.
+type Generator interface {
+	// GenerateApplications interprets the ApplicationSet and generates all relevant Applications.
+	// The expected / desired list of Applications is returned, it then needs to be reconciled
+	// against the current state of the Applications in the cluster.
+	GenerateApplications(appSet *argoprojiov1alpha1.ApplicationSet) ([]argov1alpha1.Application, error)
+}

pkg/generators/list.go

@@ -0,0 +1,29 @@
+package generators
+
+import (
+	"fmt"
+	argoprojiov1alpha1 "github.com/argoproj-labs/applicationset/api/v1alpha1"
+	argov1alpha1 "github.com/argoproj/argo-cd/pkg/apis/application/v1alpha1"
+	"sigs.k8s.io/controller-runtime/pkg/client"
+)
+
+var _ Generator = (*ListGenerator)(nil)
+
+type ListGenerator struct {
+	commonClient client.Client
+}
+
+func NewListGenerator(client client.Client) Generator {
+	g := &ListGenerator{
+		commonClient: client,
+	}
+	return g
+}
+
+func (g *ListGenerator) GenerateApplications(appSet *argoprojiov1alpha1.ApplicationSet) ([]argov1alpha1.Application, error) {
+	if appSet == nil {
+		return nil, fmt.Errorf("ApplicationSet is empty ")
+	}
+
+	return nil, nil
+}