refactor: move all port management code to standalone ports plugin

This change makes interacting with port mappings more clear - folks might previously set the port mapping to the proxy type or vice-versa.

The existing proxy:ports* commands still exist but will show a deprecation warning for a single minor release.

plugins/ports/src/subcommands/subcommands.go

@@ -0,0 +1,65 @@
+package main
+
+import (
+	"fmt"
+	"os"
+	"strings"
+
+	"github.com/dokku/dokku/plugins/common"
+	"github.com/dokku/dokku/plugins/ports"
+
+	flag "github.com/spf13/pflag"
+)
+
+// main entrypoint to all subcommands
+func main() {
+	parts := strings.Split(os.Args[0], "/")
+	subcommand := parts[len(parts)-1]
+
+	var err error
+	switch subcommand {
+	case "list":
+		args := flag.NewFlagSet("ports:list", flag.ExitOnError)
+		args.Parse(os.Args[2:])
+		appName := args.Arg(0)
+		err = ports.CommandList(appName)
+	case "add":
+		args := flag.NewFlagSet("ports:add", flag.ExitOnError)
+		args.Parse(os.Args[2:])
+		appName := args.Arg(0)
+		_, portMaps := common.ShiftString(args.Args())
+		err = ports.CommandAdd(appName, portMaps)
+	case "clear":
+		args := flag.NewFlagSet("ports:clear", flag.ExitOnError)
+		args.Parse(os.Args[2:])
+		appName := args.Arg(0)
+		err = ports.CommandClear(appName)
+	case "remove":
+		args := flag.NewFlagSet("ports:remove", flag.ExitOnError)
+		args.Parse(os.Args[2:])
+		appName := args.Arg(0)
+		_, portMaps := common.ShiftString(args.Args())
+		err = ports.CommandRemove(appName, portMaps)
+	case "set":
+		args := flag.NewFlagSet("ports:set", flag.ExitOnError)
+		args.Parse(os.Args[2:])
+		appName := args.Arg(0)
+		_, portMaps := common.ShiftString(args.Args())
+		err = ports.CommandSet(appName, portMaps)
+	case "report":
+		args := flag.NewFlagSet("ports:report", flag.ExitOnError)
+		format := args.String("format", "stdout", "format: [ stdout | json ]")
+		osArgs, infoFlag, flagErr := common.ParseReportArgs("ports", os.Args[2:])
+		if flagErr == nil {
+			args.Parse(osArgs)
+			appName := args.Arg(0)
+			err = ports.CommandReport(appName, *format, infoFlag)
+		}
+	default:
+		err = fmt.Errorf("Invalid plugin subcommand call: %s", subcommand)
+	}
+
+	if err != nil {
+		common.LogFailWithError(err)
+	}
+}