[feature] Email notifications for new / closed moderation reports (#1628)

* start fiddling about with email sending to allow multiple recipients

* do some fiddling

* notifs working

* notify on closed report

* finishing up

* envparsing

* use strings.ContainsAny

3 files changed, 73 insertions, 0 deletions

diff --git a/internal/db/bundb/instance.go b/internal/db/bundb/instance.go
index b4bdeb1d9..4fa898639 100644
--- a/internal/db/bundb/instance.go
+++ b/internal/db/bundb/instance.go
@@ -156,3 +156,34 @@ func (i *instanceDB) GetInstanceAccounts(ctx context.Context, domain string, max
 
 	return accounts, nil
 }
+
+func (i *instanceDB) GetInstanceModeratorAddresses(ctx context.Context) ([]string, db.Error) {
+	addresses := []string{}
+
+	// Select email addresses of approved, confirmed,
+	// and enabled moderators or admins.
+
+	q := i.conn.
+		NewSelect().
+		TableExpr("? AS ?", bun.Ident("users"), bun.Ident("user")).
+		Column("user.email").
+		Where("? = ?", bun.Ident("user.approved"), true).
+		Where("? IS NOT NULL", bun.Ident("user.confirmed_at")).
+		Where("? = ?", bun.Ident("user.disabled"), false).
+		WhereGroup(" AND ", func(q *bun.SelectQuery) *bun.SelectQuery {
+			return q.
+				Where("? = ?", bun.Ident("user.moderator"), true).
+				WhereOr("? = ?", bun.Ident("user.admin"), true)
+		}).
+		OrderExpr("? ASC", bun.Ident("user.email"))
+
+	if err := q.Scan(ctx, &addresses); err != nil {
+		return nil, i.conn.ProcessError(err)
+	}
+
+	if len(addresses) == 0 {
+		return nil, db.ErrNoEntries
+	}
+
+	return addresses, nil
+}
diff --git a/internal/db/bundb/instance_test.go b/internal/db/bundb/instance_test.go
index 4269df5ca..580a7699b 100644
--- a/internal/db/bundb/instance_test.go
+++ b/internal/db/bundb/instance_test.go
@@ -24,6 +24,8 @@ import (
 	"github.com/stretchr/testify/suite"
 	"github.com/superseriousbusiness/gotosocial/internal/config"
 	"github.com/superseriousbusiness/gotosocial/internal/db"
+	"github.com/superseriousbusiness/gotosocial/internal/gtsmodel"
+	"github.com/superseriousbusiness/gotosocial/testrig"
 )
 
 type InstanceTestSuite struct {
@@ -90,6 +92,42 @@ func (suite *InstanceTestSuite) TestGetInstanceAccounts() {
 	suite.Len(accounts, 1)
 }
 
+func (suite *InstanceTestSuite) TestGetInstanceModeratorAddressesOK() {
+	// We have one admin user by default.
+	addresses, err := suite.db.GetInstanceModeratorAddresses(context.Background())
+	suite.NoError(err)
+	suite.EqualValues([]string{"admin@example.org"}, addresses)
+}
+
+func (suite *InstanceTestSuite) TestGetInstanceModeratorAddressesZorkAsModerator() {
+	// Promote zork to moderator role.
+	testUser := &gtsmodel.User{}
+	*testUser = *suite.testUsers["local_account_1"]
+	testUser.Moderator = testrig.TrueBool()
+	if err := suite.db.UpdateUser(context.Background(), testUser, "moderator"); err != nil {
+		suite.FailNow(err.Error())
+	}
+
+	addresses, err := suite.db.GetInstanceModeratorAddresses(context.Background())
+	suite.NoError(err)
+	suite.EqualValues([]string{"admin@example.org", "zork@example.org"}, addresses)
+}
+
+func (suite *InstanceTestSuite) TestGetInstanceModeratorAddressesNoAdmin() {
+	// Demote admin from admin + moderator roles.
+	testUser := &gtsmodel.User{}
+	*testUser = *suite.testUsers["admin_account"]
+	testUser.Admin = testrig.FalseBool()
+	testUser.Moderator = testrig.FalseBool()
+	if err := suite.db.UpdateUser(context.Background(), testUser, "admin", "moderator"); err != nil {
+		suite.FailNow(err.Error())
+	}
+
+	addresses, err := suite.db.GetInstanceModeratorAddresses(context.Background())
+	suite.ErrorIs(err, db.ErrNoEntries)
+	suite.Empty(addresses)
+}
+
 func TestInstanceTestSuite(t *testing.T) {
 	suite.Run(t, new(InstanceTestSuite))
 }
diff --git a/internal/db/instance.go b/internal/db/instance.go
index dff471193..3166a0a18 100644
--- a/internal/db/instance.go
+++ b/internal/db/instance.go
@@ -42,4 +42,8 @@ type Instance interface {
 
 	// GetInstancePeers returns a slice of instances that the host instance knows about.
 	GetInstancePeers(ctx context.Context, includeSuspended bool) ([]*gtsmodel.Instance, Error)
+
+	// GetInstanceModeratorAddresses returns a slice of email addresses belonging to active
+	// (as in, not suspended) moderators + admins on this instance.
+	GetInstanceModeratorAddresses(ctx context.Context) ([]string, Error)
 }