Base CUE, def, schemas

codegen/tool/main.go

@@ -0,0 +1,74 @@
+package main
+
+import (
+	"encoding/json"
+	"flag"
+	"fmt"
+	"os"
+	"text/template"
+
+	"github.com/cortezaproject/corteza-server/pkg/cli"
+)
+
+type (
+	task struct {
+		Template string      `json:"template"`
+		Output   string      `json:"output"`
+		Syntax   string      `json:"syntax"`
+		Payload  interface{} `json:"payload"`
+	}
+)
+
+var (
+	verbose     bool
+	showHelp    bool
+	tplRootPath string
+)
+
+func init() {
+	flag.BoolVar(&showHelp, "h", false, "show help")
+	flag.BoolVar(&verbose, "v", false, "be verbose")
+	flag.StringVar(&tplRootPath, "p", "codegen/assets/templates", "location of the template files")
+	flag.Parse()
+}
+
+// Takes JSON input with codegen tasks and definitions and generates files
+func main() {
+	if showHelp {
+		flag.PrintDefaults()
+		os.Exit(0)
+	}
+
+	var (
+		input = json.NewDecoder(os.Stdin)
+		tasks = make([]*task, 0)
+		tpl   *template.Template
+		err   error
+	)
+
+	print("Waiting for stdin ...\n")
+	if err = input.Decode(&tasks); err != nil {
+		cli.HandleError(fmt.Errorf("failed to decode input from standard input: %v", err))
+	}
+
+	if tpl, err = LoadTemplates(BaseTemplate(), tplRootPath); err != nil {
+		cli.HandleError(fmt.Errorf("failed to load templates: %v", err))
+	}
+
+	for _, j := range tasks {
+		switch j.Syntax {
+		case "go":
+			print(fmt.Sprintf("generating %s (from %s) ...", j.Output, j.Template))
+			if err = GoTemplate(j.Output, tpl.Lookup(j.Template), j.Payload); err != nil {
+				cli.HandleError(fmt.Errorf("failed to write template: %v", err))
+			}
+			print("done\n")
+		}
+	}
+}
+
+func print(msg string) {
+	if verbose {
+		_, _ = fmt.Fprint(os.Stderr, msg)
+	}
+}

codegen/tool/templating.go

@@ -0,0 +1,78 @@
+package main
+
+import (
+	"bytes"
+	"fmt"
+	"go/format"
+	"io"
+	"io/ioutil"
+	"os"
+	"path/filepath"
+	"strings"
+	"text/template"
+
+	"github.com/Masterminds/sprig"
+)
+
+func BaseTemplate() *template.Template {
+	return template.New("").
+		Funcs(sprig.TxtFuncMap())
+}
+
+func LoadTemplates(rTpl *template.Template, rootDir string) (*template.Template, error) {
+	cleanRoot := filepath.Clean(rootDir)
+	pfx := len(cleanRoot) + 1
+
+	return rTpl, filepath.Walk(cleanRoot, func(path string, info os.FileInfo, err error) error {
+		if info.IsDir() || !strings.HasSuffix(path, ".tpl") || err != nil {
+			return err
+		}
+
+		b, err := ioutil.ReadFile(path)
+		if err != nil {
+			return err
+		}
+
+		name := path[pfx:]
+		rTpl, err = rTpl.New(name).Parse(string(b))
+
+		return err
+	})
+}
+
+func GoTemplate(dst string, tpl *template.Template, payload interface{}) (err error) {
+	var output io.WriteCloser
+	buf := bytes.Buffer{}
+
+	if tpl == nil {
+		return fmt.Errorf("could not find template for %s", dst)
+	}
+
+	if err := tpl.Execute(&buf, payload); err != nil {
+		return err
+	}
+
+	fmtsrc, err := format.Source(buf.Bytes())
+	if err != nil {
+		_, _ = fmt.Fprintf(os.Stderr, "%s fmt warn: %v\n", dst, err)
+
+		err = nil
+		fmtsrc = buf.Bytes()
+	}
+
+	if dst == "" || dst == "-" {
+		output = os.Stdout
+	} else {
+		if output, err = os.Create(dst); err != nil {
+			return err
+		}
+
+		defer output.Close()
+	}
+
+	if _, err = output.Write(fmtsrc); err != nil {
+		return err
+	}
+
+	return nil
+}