Support falling back to ruby version of checkers

Rename the ruby scripts to have `-ruby` suffix and add a symlink
for both to `./gitlab-shell`. The executable name will be used to
determine how args will be parsed.

For now, we only parse the arguments for gitlab-shell commands. If
the executable is `gitlab-shell-authorized-keys-check` or
`gitlab-shell-authorized-principals-check`, it'll always fallback
to the ruby version.

Ruby specs test the ruby script, the fallback from go to ruby and
go implementation of both (still pending).

1 files changed, 15 insertions, 7 deletions

diff --git a/go/internal/command/fallback/fallback.go b/go/internal/command/fallback/fallback.go
index f525a57..cec94d5 100644
--- a/go/internal/command/fallback/fallback.go
+++ b/go/internal/command/fallback/fallback.go
@@ -1,14 +1,22 @@
 package fallback
 
 import (
+	"fmt"
 	"os"
 	"path/filepath"
 	"syscall"
+
+	"gitlab.com/gitlab-org/gitlab-shell/go/internal/command/commandargs"
 )
 
+type CommandArgs interface {
+	Executable() commandargs.Executable
+	Arguments() []string
+}
+
 type Command struct {
 	RootDir string
-	Args    []string
+	Args    CommandArgs
 }
 
 var (
@@ -16,15 +24,15 @@ var (
 	execFunc = syscall.Exec
 )
 
-const (
-	RubyProgram = "gitlab-shell-ruby"
-)
-
 func (c *Command) Execute() error {
-	rubyCmd := filepath.Join(c.RootDir, "bin", RubyProgram)
+	rubyCmd := filepath.Join(c.RootDir, "bin", c.fallbackProgram())
 
 	// Ensure rubyArgs[0] is the full path to gitlab-shell-ruby
-	rubyArgs := append([]string{rubyCmd}, c.Args[1:]...)
+	rubyArgs := append([]string{rubyCmd}, c.Args.Arguments()...)
 
 	return execFunc(rubyCmd, rubyArgs, os.Environ())
 }
+
+func (c *Command) fallbackProgram() string {
+	return fmt.Sprintf("%s-ruby", c.Args.Executable())
+}