Mono repo -> Master (#22553)

Combines the following repositories into one:

https://github.com/mattermost/mattermost-server
https://github.com/mattermost/mattermost-webapp
https://github.com/mattermost/focalboard
https://github.com/mattermost/mattermost-plugin-playbooks

server/platform/services/slackimport/parsers.go

@@ -0,0 +1,50 @@
+// Copyright (c) 2015-present Mattermost, Inc. All Rights Reserved.
+// See LICENSE.txt for license information.
+
+package slackimport
+
+import (
+	"encoding/json"
+	"io"
+
+	"github.com/mattermost/mattermost-server/v6/model"
+	"github.com/mattermost/mattermost-server/v6/server/platform/shared/mlog"
+)
+
+func slackParseChannels(data io.Reader, channelType model.ChannelType) ([]slackChannel, error) {
+	decoder := json.NewDecoder(data)
+
+	var channels []slackChannel
+	if err := decoder.Decode(&channels); err != nil {
+		mlog.Warn("Slack Import: Error occurred when parsing some Slack channels. Import may work anyway.", mlog.Err(err))
+		return channels, err
+	}
+
+	for i := range channels {
+		channels[i].Type = channelType
+	}
+
+	return channels, nil
+}
+
+func slackParseUsers(data io.Reader) ([]slackUser, error) {
+	decoder := json.NewDecoder(data)
+
+	var users []slackUser
+	err := decoder.Decode(&users)
+	// This actually returns errors that are ignored.
+	// In this case it is erroring because of a null that Slack
+	// introduced. So we just return the users here.
+	return users, err
+}
+
+func slackParsePosts(data io.Reader) ([]slackPost, error) {
+	decoder := json.NewDecoder(data)
+
+	var posts []slackPost
+	if err := decoder.Decode(&posts); err != nil {
+		mlog.Warn("Slack Import: Error occurred when parsing some Slack posts. Import may work anyway.", mlog.Err(err))
+		return posts, err
+	}
+	return posts, nil
+}