CI: move grabpl verify-drone (#55057)

* move grabpl verify-drone

pkg/build/cmd/main.go

@@ -114,6 +114,11 @@ func main() {
 			ArgsUsage: "<api-key>",
 			Action:    ArgCountWrapper(1, PublishMetrics),
 		},
+		{
+			Name:   "verify-drone",
+			Usage:  "Verify Drone configuration",
+			Action: VerifyDrone,
+		},
 		{
 			Name:   "export-version",
 			Usage:  "Exports version in dist/grafana.version",

pkg/build/cmd/verifydrone.go

@@ -0,0 +1,123 @@
+package main
+
+import (
+	"errors"
+	"flag"
+	"fmt"
+	"io"
+	"log"
+	"os"
+
+	"github.com/drone/drone-cli/drone/lint"
+	"github.com/drone/drone-cli/drone/starlark"
+
+	"github.com/google/go-cmp/cmp"
+
+	"github.com/grafana/grafana/pkg/build/fsutil"
+	cliv1 "github.com/urfave/cli"
+	"github.com/urfave/cli/v2"
+	"gopkg.in/yaml.v3"
+)
+
+func VerifyDrone(c *cli.Context) error {
+	const yml = ".drone.yml"
+	const backup = ".drone.yml.bak"
+
+	if err := fsutil.CopyFile(yml, backup); err != nil {
+		return cli.NewExitError(fmt.Sprintf("failed to copy %s to %s: %s", yml, backup, err), 1)
+	}
+	defer func() {
+		if err := os.Remove(yml); err != nil {
+			log.Printf("Failed to rename %s to %s", backup, yml)
+		}
+		if err := os.Rename(backup, yml); err != nil {
+			log.Printf("Failed to rename %s to %s", backup, yml)
+		}
+	}()
+
+	flags := &flag.FlagSet{}
+	for _, flag := range starlark.Command.Flags {
+		flag.Apply(flags)
+	}
+	cStarlark := cliv1.NewContext(cliv1.NewApp(), flags, nil)
+	action := starlark.Command.Action.(func(*cliv1.Context))
+	action(cStarlark)
+
+	if err := verifyYAML(yml, backup); err != nil {
+		return err
+	}
+
+	flags = &flag.FlagSet{}
+	for _, flag := range lint.Command.Flags {
+		flag.Apply(flags)
+	}
+	err := flags.Set("trusted", "true")
+	if err != nil {
+		return err
+	}
+	cLint := cliv1.NewContext(cliv1.NewApp(), flags, nil)
+	actionE := lint.Command.Action.(func(*cliv1.Context) error)
+	if err := actionE(cLint); err != nil {
+		return err
+	}
+
+	log.Printf("%s is valid", yml)
+
+	return nil
+}
+
+func readConfig(fpath string) ([]map[string]interface{}, error) {
+	//nolint:gosec
+	f, err := os.Open(fpath)
+	if err != nil {
+		return nil, cli.NewExitError(fmt.Sprintf("failed to read %s: %s", fpath, err), 1)
+	}
+	defer func() {
+		if err := f.Close(); err != nil {
+			log.Println("error closing file", err)
+		}
+	}()
+
+	// The YAML stream may contain multiple pipeline configurations, read them all
+	dec := yaml.NewDecoder(f)
+	var c []map[string]interface{}
+	for {
+		var m map[string]interface{}
+		if err := dec.Decode(&m); err != nil {
+			if errors.Is(err, io.EOF) {
+				break
+			}
+			return nil, cli.NewExitError(fmt.Sprintf("Failed to decode %s: %s", fpath, err), 1)
+		}
+
+		if m["kind"] == "signature" {
+			log.Printf("Ignoring a signature")
+			continue
+		}
+
+		c = append(c, m)
+	}
+
+	return c, nil
+}
+
+func verifyYAML(yml, backup string) error {
+	log.Printf("Comparing %s and %s", yml, backup)
+
+	c1, err := readConfig(yml)
+	if err != nil {
+		return err
+	}
+
+	c2, err := readConfig(backup)
+	if err != nil {
+		return err
+	}
+
+	if !cmp.Equal(c1, c2) {
+		return cli.NewExitError(fmt.Sprintf("%s is out of sync with .drone.star - regenerate it with drone starlark convert",
+			yml), 1)
+	}
+
+	return nil
+}