Includes mmctl into the mono-repo (#23091)

* Includes mmctl into the mono-repo

* Update to use the new public module paths

* Adds docs check to the mmctl CI

* Fix public utils import path

* Tidy up modules

* Fix linter

* Update CI tasks to use the new file structure

* Update CI references

server/cmd/mmctl/commands/channelargs.go

@@ -0,0 +1,124 @@
+// Copyright (c) 2015-present Mattermost, Inc. All Rights Reserved.
+// See LICENSE.txt for license information.
+
+package commands
+
+import (
+	"errors"
+	"fmt"
+	"strings"
+
+	"github.com/hashicorp/go-multierror"
+	"github.com/mattermost/mattermost-server/server/public/model"
+
+	"github.com/mattermost/mattermost-server/server/v8/cmd/mmctl/client"
+)
+
+const channelArgSeparator = ":"
+
+func getChannelsFromChannelArgs(c client.Client, channelArgs []string) []*model.Channel {
+	channels := make([]*model.Channel, 0, len(channelArgs))
+	for _, channelArg := range channelArgs {
+		channel := getChannelFromChannelArg(c, channelArg)
+		channels = append(channels, channel)
+	}
+	return channels
+}
+
+func parseChannelArg(channelArg string) (string, string) {
+	result := strings.SplitN(channelArg, channelArgSeparator, 2)
+	if len(result) == 1 {
+		return "", channelArg
+	}
+	return result[0], result[1]
+}
+
+func getChannelFromChannelArg(c client.Client, channelArg string) *model.Channel {
+	teamArg, channelPart := parseChannelArg(channelArg)
+	if teamArg == "" && channelPart == "" {
+		return nil
+	}
+
+	if checkDots(channelPart) || checkSlash(channelPart) {
+		return nil
+	}
+
+	var channel *model.Channel
+	if teamArg != "" {
+		team := getTeamFromTeamArg(c, teamArg)
+		if team == nil {
+			return nil
+		}
+
+		channel, _, _ = c.GetChannelByNameIncludeDeleted(channelPart, team.Id, "")
+	}
+
+	if channel == nil {
+		channel, _, _ = c.GetChannel(channelPart, "")
+	}
+
+	return channel
+}
+
+// getChannelsFromArgs obtains channels by the `channelArgs` parameter. It can return channels and errors
+// at the same time
+//
+//nolint:golint,unused
+func getChannelsFromArgs(c client.Client, channelArgs []string) ([]*model.Channel, error) {
+	var channels []*model.Channel
+	var result *multierror.Error
+	for _, channelArg := range channelArgs {
+		channel, err := getChannelFromArg(c, channelArg)
+		if err != nil {
+			result = multierror.Append(result, err)
+			continue
+		}
+		channels = append(channels, channel)
+	}
+	return channels, result.ErrorOrNil()
+}
+
+//nolint:golint,unused
+func getChannelFromArg(c client.Client, arg string) (*model.Channel, error) {
+	teamArg, channelArg := parseChannelArg(arg)
+	if teamArg == "" && channelArg == "" {
+		return nil, fmt.Errorf("invalid channel argument %q", arg)
+	}
+	if checkDots(channelArg) || checkSlash(channelArg) {
+		return nil, fmt.Errorf(`invalid channel argument. Cannot contain ".." nor "/"`)
+	}
+	var channel *model.Channel
+	var response *model.Response
+	if teamArg != "" {
+		team, err := getTeamFromArg(c, teamArg)
+		if err != nil {
+			return nil, err
+		}
+		channel, response, err = c.GetChannelByNameIncludeDeleted(channelArg, team.Id, "")
+		if err != nil {
+			err = ExtractErrorFromResponse(response, err)
+			var nfErr *NotFoundError
+			var badRequestErr *BadRequestError
+			if !errors.As(err, &nfErr) && !errors.As(err, &badRequestErr) {
+				return nil, err
+			}
+		}
+	}
+	if channel != nil {
+		return channel, nil
+	}
+	var err error
+	channel, response, err = c.GetChannel(channelArg, "")
+	if err != nil {
+		nErr := ExtractErrorFromResponse(response, err)
+		var nfErr *NotFoundError
+		var badRequestErr *BadRequestError
+		if !errors.As(nErr, &nfErr) && !errors.As(nErr, &badRequestErr) {
+			return nil, nErr
+		}
+	}
+	if channel == nil {
+		return nil, ErrEntityNotFound{Type: "channel", ID: arg}
+	}
+	return channel, nil
+}