Imports github.com/mattermost/mattermost-server/mlog github.com/mattermost/mattermost-server/model github.com/mattermost/mattermost-server/services/filesstore github.com/mattermost/mattermost-server/utils gopkg.in/mail.v2 github.com/jaytaylor/html2text Standard library imports bytes crypto/tls encoding/json errors fmt io mime net net/http net/mail net/smtp os strings time