Schema: Refactor plugin code generation (#58901)

* wip

* wip

* almost there..

* wip - change so it can run.

* treelist is working.

* support CODEGEN_VERIFY env variable

* use log.fatal

* comment out old PluginTreeList code generation

* cleanup

* rename corelist package files

* fix makefile

* move pkg/codegen/pluggen.go to pkg/plugins/codegen

* copy and refactor files to pkg/plugins/codegen

* use pkg/plugins/codegen instead of pkg/codegen for core plugins code gen

* remove unneeded files

* remove unused code to resolve linting errors

* adapters first hack

* added flattener

* add back ignore build tags to go generate file

* cleaned up the code a bit.

* seems to work, needs to do some refactoring of the GoTypesJenns and TSTypesJenny.

* one more step, going to get upstream changes in this branch.

* working but need to run import tmpl in jenny_schemapath to have the proper imports.

* added header to generated files.

* added missing jenny.

* preventing plugins with multiple decls/schemas to insert multiple lines in corelist.

* fixed so we use Slot type from kindsys to detect if its group.

* adding a go jenny that only runs if the plugin has a backend.

* added version object to generated ts.

* generating the ts types with the same output as prior to this refactoring.

* removed code that is replaced by the jenny pattern.

* removed the go code that isn't used anymore.

* removed some more unused code and renamed pluggen to util_ts

* fixed linting issue.

* removed unused vars.

* use a jenny list postprocessor for header injection

* moved decl and decl_parser to pfs.

* removed the pre-pended header in the gotypes jenny since it is done in the postprocess.

* moved decl to pfs.

* removed unused template.

Co-authored-by: Marcus Efraimsson <marcus.efraimsson@gmail.com>

pkg/plugins/codegen/util_ts.go

@@ -0,0 +1,73 @@
+package codegen
+
+import (
+	"fmt"
+	"sort"
+	"strings"
+
+	"cuelang.org/go/cue/ast"
+	tsast "github.com/grafana/cuetsy/ts/ast"
+	"github.com/grafana/grafana/pkg/plugins/pfs"
+)
+
+// CUE import paths, mapped to corresponding TS import paths. An empty value
+// indicates the import path should be dropped in the conversion to TS. Imports
+// not present in the list are not not allowed, and code generation will fail.
+var importMap = map[string]string{
+	"github.com/grafana/thema":                                      "",
+	"github.com/grafana/grafana/packages/grafana-schema/src/schema": "@grafana/schema",
+}
+
+func init() {
+	allow := pfs.PermittedCUEImports()
+	strsl := make([]string, 0, len(importMap))
+	for p := range importMap {
+		strsl = append(strsl, p)
+	}
+
+	sort.Strings(strsl)
+	sort.Strings(allow)
+	if strings.Join(strsl, "") != strings.Join(allow, "") {
+		panic("CUE import map is not the same as permitted CUE import list - these files must be kept in sync!")
+	}
+}
+
+// mapCUEImportToTS maps the provided CUE import path to the corresponding
+// TypeScript import path in generated code.
+//
+// Providing an import path that is not allowed results in an error. If a nil
+// error and empty string are returned, the import path should be dropped in
+// generated code.
+func mapCUEImportToTS(path string) (string, error) {
+	i, has := importMap[path]
+	if !has {
+		return "", fmt.Errorf("import %q in models.cue is not allowed", path)
+	}
+	return i, nil
+}
+
+// TODO convert this to use cuetsy ts types, once import * form is supported
+func convertImport(im *ast.ImportSpec) (tsast.ImportSpec, error) {
+	tsim := tsast.ImportSpec{}
+	pkg, err := mapCUEImportToTS(strings.Trim(im.Path.Value, "\""))
+	if err != nil || pkg == "" {
+		// err should be unreachable if paths has been verified already
+		// Empty string mapping means skip it
+		return tsim, err
+	}
+
+	tsim.From = tsast.Str{Value: pkg}
+
+	if im.Name != nil && im.Name.String() != "" {
+		tsim.AsName = im.Name.String()
+	} else {
+		sl := strings.Split(im.Path.Value, "/")
+		final := sl[len(sl)-1]
+		if idx := strings.Index(final, ":"); idx != -1 {
+			tsim.AsName = final[idx:]
+		} else {
+			tsim.AsName = final
+		}
+	}
+	return tsim, nil
+}