From 3cc08a50d62fbd013729cf216407146889caafb3 Mon Sep 17 00:00:00 2001
From: Sebastian Widmer <sebastian.widmer@vshn.net>
Date: Wed, 19 Jun 2024 13:35:37 +0200
Subject: [PATCH] Draft: automate exporting CV spec

---
 tools/importcvspec/importcvspec.go | 97 ++++++++++++++++++++++++++++++
 tools/impt/impt_test.go            | 48 +++++++++++++++
 tools/toimp/toimp.go               | 15 +++++
 3 files changed, 160 insertions(+)
 create mode 100644 tools/importcvspec/importcvspec.go
 create mode 100644 tools/impt/impt_test.go
 create mode 100644 tools/toimp/toimp.go

diff --git a/tools/importcvspec/importcvspec.go b/tools/importcvspec/importcvspec.go
new file mode 100644
index 0000000..4f48c4b
--- /dev/null
+++ b/tools/importcvspec/importcvspec.go
@@ -0,0 +1,97 @@
+package main
+
+import (
+	"fmt"
+	"go/ast"
+	"go/build"
+	"go/importer"
+	"go/parser"
+	"go/token"
+	"go/types"
+	"log"
+
+	"golang.org/x/exp/maps"
+)
+
+func main() {
+	fset := token.NewFileSet()
+
+	pkg := parseWithTypes(fset)
+	fmt.Println("Package parsed and type checked", pkg.Name())
+
+	cvs := pkg.Scope().Lookup("ClusterVersionSpec")
+	if cvs == nil {
+		log.Fatal("ClusterVersionSpec not found")
+	}
+	fmt.Println("ClusterVersionSpec found")
+	fmt.Println(types.ObjectString(cvs, types.RelativeTo(pkg)))
+	str, ok := cvs.Type().Underlying().(*types.Struct)
+	if !ok {
+		log.Fatal("ClusterVersionSpec is not a struct")
+	}
+
+	toExport := extractNamed([]types.Object{cvs}, str)
+
+	fmt.Println("####################")
+
+	for _, obj := range toExport {
+		fmt.Println(types.ObjectString(obj, types.RelativeTo(pkg)))
+	}
+
+	fmt.Println("####################")
+
+}
+
+func extractNamed(toExport []types.Object, cvs types.Type) []types.Object {
+	switch t := cvs.(type) {
+	case *types.Named:
+		fmt.Println("Named type", t.Obj())
+		toExport = append(toExport, t.Obj())
+		toExport = extractNamed(toExport, t.Underlying())
+	case *types.Basic:
+	case *types.Pointer:
+		toExport = extractNamed(toExport, t.Elem())
+	case *types.Array:
+		toExport = extractNamed(toExport, t.Elem())
+	case *types.Slice:
+		toExport = extractNamed(toExport, t.Elem())
+	case *types.Map:
+		toExport = extractNamed(toExport, t.Key())
+		toExport = extractNamed(toExport, t.Elem())
+	case *types.Struct:
+		for i := 0; i < t.NumFields(); i++ {
+			field := t.Field(i)
+			fmt.Printf("%s (%T)\n", field.String(), field.Type())
+			toExport = extractNamed(toExport, field.Type())
+		}
+	default:
+		log.Fatalf("Type not yet supported %T", t)
+	}
+	return toExport
+}
+
+func parseWithTypes(fset *token.FileSet) *types.Package {
+	imp, err := build.Import("github.com/openshift/api/config/v1", "", build.FindOnly)
+	if err != nil {
+		log.Fatal(err)
+	}
+	fmt.Println("Import from: ", imp.Dir)
+	rawPkgs, err := parser.ParseDir(fset, imp.Dir, nil, parser.SkipObjectResolution)
+	if err != nil {
+		log.Fatal(err)
+	}
+	rawPkg := rawPkgs["v1"]
+	info := types.Info{
+		Types: make(map[ast.Expr]types.TypeAndValue),
+		Defs:  make(map[*ast.Ident]types.Object),
+		Uses:  make(map[*ast.Ident]types.Object),
+	}
+	conf := types.Config{
+		Importer: importer.ForCompiler(fset, "source", nil),
+	}
+	pkg, err := conf.Check(imp.Dir, fset, maps.Values(rawPkg.Files), &info)
+	if err != nil {
+		log.Fatal(err)
+	}
+	return pkg
+}
diff --git a/tools/impt/impt_test.go b/tools/impt/impt_test.go
new file mode 100644
index 0000000..9a5652d
--- /dev/null
+++ b/tools/impt/impt_test.go
@@ -0,0 +1,48 @@
+package impt_test
+
+import (
+	"fmt"
+	"go/ast"
+	"go/build"
+	"go/importer"
+	"go/parser"
+	"go/token"
+	"go/types"
+	"log"
+	"testing"
+
+	"golang.org/x/exp/maps"
+)
+
+func TestImport(t *testing.T) {
+	fset := token.NewFileSet()
+	pt := parseWithTypes(fset)
+	fmt.Println("Package parsed and type checked", pt.Name())
+	fmt.Println("Package path", pt)
+}
+
+func parseWithTypes(fset *token.FileSet) *types.Package {
+	imp, err := build.Import("github.com/appuio/openshift-upgrade-controller/tools/toimp", "", build.FindOnly)
+	if err != nil {
+		log.Fatal(err)
+	}
+	fmt.Println("Import from: ", imp.Dir)
+	rawPkgs, err := parser.ParseDir(fset, imp.Dir, nil, parser.SkipObjectResolution)
+	if err != nil {
+		log.Fatal(err)
+	}
+	rawPkg := rawPkgs["toimp"]
+	info := types.Info{
+		Types: make(map[ast.Expr]types.TypeAndValue),
+		Defs:  make(map[*ast.Ident]types.Object),
+		Uses:  make(map[*ast.Ident]types.Object),
+	}
+	conf := types.Config{
+		Importer: importer.ForCompiler(fset, "source", nil),
+	}
+	pkg, err := conf.Check(imp.Dir, fset, maps.Values(rawPkg.Files), &info)
+	if err != nil {
+		log.Fatal(err)
+	}
+	return pkg
+}
diff --git a/tools/toimp/toimp.go b/tools/toimp/toimp.go
new file mode 100644
index 0000000..df35736
--- /dev/null
+++ b/tools/toimp/toimp.go
@@ -0,0 +1,15 @@
+package toimp
+
+import configv1 "github.com/openshift/api/config/v1"
+
+type ClusterID string
+
+type LocalSpec struct {
+	ClusterID ClusterID `json:"clusterID"`
+}
+
+func Convert(ls LocalSpec) configv1.ClusterVersionSpec {
+	cvs := configv1.ClusterVersionSpec{}
+	cvs.ClusterID = configv1.ClusterID(ls.ClusterID)
+	return cvs
+}