feat(registry): резолвинг провайдера по имени

internal/provider/registry/registry.go

@@ -0,0 +1,28 @@
+package registry
+
+import (
+	"fmt"
+
+	"github.com/vasyakrg/dns-autoresolver/internal/provider"
+)
+
+// Registry resolves providers by name.
+type Registry struct {
+	m map[string]provider.Provider
+}
+
+func New() *Registry {
+	return &Registry{m: make(map[string]provider.Provider)}
+}
+
+func (r *Registry) Register(p provider.Provider) {
+	r.m[p.Name()] = p
+}
+
+func (r *Registry) ByName(name string) (provider.Provider, error) {
+	p, ok := r.m[name]
+	if !ok {
+		return nil, fmt.Errorf("registry: unknown provider %q", name)
+	}
+	return p, nil
+}

internal/provider/registry/registry_test.go

@@ -0,0 +1,35 @@
+package registry
+
+import (
+	"context"
+	"testing"
+
+	"github.com/vasyakrg/dns-autoresolver/internal/diff"
+	"github.com/vasyakrg/dns-autoresolver/internal/model"
+	"github.com/vasyakrg/dns-autoresolver/internal/provider"
+)
+
+type fakeProvider struct{ name string }
+
+func (f fakeProvider) Name() string { return f.name }
+func (fakeProvider) ListZones(context.Context, provider.Credentials) ([]provider.Zone, error) {
+	return nil, nil
+}
+func (fakeProvider) GetRecords(context.Context, provider.Credentials, string) ([]model.Record, error) {
+	return nil, nil
+}
+func (fakeProvider) ApplyChanges(context.Context, provider.Credentials, string, diff.Changeset) error {
+	return nil
+}
+
+func TestRegistryByName(t *testing.T) {
+	r := New()
+	r.Register(fakeProvider{name: "selectel"})
+	p, err := r.ByName("selectel")
+	if err != nil || p.Name() != "selectel" {
+		t.Fatalf("expected selectel, got %v err=%v", p, err)
+	}
+	if _, err := r.ByName("unknown"); err == nil {
+		t.Fatal("expected error for unknown provider")
+	}
+}