smtp + email confirmation (#285)

* add smtp configuration

* add email confirm + reset templates

* add email sender to testrig

* flesh out the email sender interface

* go fmt

* golint

* update from field with more clarity

* tidy up the email formatting

* fix tests

* add email sender to processor

* tidy client api processing a bit

* further tidying in fromClientAPI

* pin new account to user

* send msg to processor on new account creation

* generate confirm email uri

* remove emailer from account processor again

* add processCreateAccountFromClientAPI

* move emailer accountprocessor => userprocessor

* add email sender to user processor

* SendConfirmEmail function

* add noop email sender

* use noop email sender in tests

* only assemble message if callback is not nil

* use noop email sender if no smtp host is defined

* minify email html before sending

* fix wrong email address

* email confirm test

* fmt

* serve web hndler

* add email confirm handler

* init test log properly on testrig

* log emails that *would* have been sent

* go fmt ./...

* unexport confirm email handler

* updatedAt

* test confirm email function

* don't allow tokens older than 7 days

* change error message a bit

* add basic smtp docs

* add a few more snippets

* typo

* add email sender to outbox tests

* don't use dutch wikipedia link

* don't minify email html

1 files changed, 60 insertions, 0 deletions

diff --git a/internal/email/sender.go b/internal/email/sender.go
new file mode 100644
index 000000000..a6a9abe55
--- /dev/null
+++ b/internal/email/sender.go
@@ -0,0 +1,60 @@
+/*
+   GoToSocial
+   Copyright (C) 2021 GoToSocial Authors admin@gotosocial.org
+
+   This program is free software: you can redistribute it and/or modify
+   it under the terms of the GNU Affero General Public License as published by
+   the Free Software Foundation, either version 3 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU Affero General Public License for more details.
+
+   You should have received a copy of the GNU Affero General Public License
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+package email
+
+import (
+	"fmt"
+	"html/template"
+	"net/smtp"
+
+	"github.com/superseriousbusiness/gotosocial/internal/config"
+)
+
+// Sender contains functions for sending emails to instance users/new signups.
+type Sender interface {
+	// SendConfirmEmail sends a 'please confirm your email' style email to the given toAddress, with the given data.
+	SendConfirmEmail(toAddress string, data ConfirmData) error
+
+	// SendResetEmail sends a 'reset your password' style email to the given toAddress, with the given data.
+	SendResetEmail(toAddress string, data ResetData) error
+}
+
+// NewSender returns a new email Sender interface with the given configuration, or an error if something goes wrong.
+func NewSender(cfg *config.Config) (Sender, error) {
+	t, err := loadTemplates(cfg.TemplateConfig.BaseDir)
+	if err != nil {
+		return nil, err
+	}
+
+	auth := smtp.PlainAuth("", cfg.SMTPConfig.Username, cfg.SMTPConfig.Password, cfg.SMTPConfig.Host)
+
+	return &sender{
+		hostAddress: fmt.Sprintf("%s:%d", cfg.SMTPConfig.Host, cfg.SMTPConfig.Port),
+		from:        cfg.SMTPConfig.From,
+		auth:        auth,
+		template:    t,
+	}, nil
+}
+
+type sender struct {
+	hostAddress string
+	from        string
+	auth        smtp.Auth
+	template    *template.Template
+}