[feature] Instance rules (#2125)

* init instance rules database model, admin api

* expose instance rules in public instance api

* public /api/v1/instance/rules route

* GET ruleById

* createRule route

* createRule auth check

* updateRule

* deleteRule

* list rules on about page

* ruleGet auth

* add about page ids for anchors

* process and store adding violated rules to reports

* admin api models for instance rules

* instance rule edit frontend

* change rule inputs to textareas

* database fixes after rebase (#2124)

* remove unused imports

* fix db migration column name

* fix tests

* fix more tests

* fix postgres error with wrongly used Ident

* add some tests, fiddle with rule model a bit, fix postgres migration

* swagger docs

---------

Co-authored-by: tsmethurst <tobi.smethurst@protonmail.com>

10 files changed, 444 insertions, 0 deletions

diff --git a/internal/db/bundb/bundb.go b/internal/db/bundb/bundb.go
index ad9053e6e..e92234f81 100644
--- a/internal/db/bundb/bundb.go
+++ b/internal/db/bundb/bundb.go
@@ -72,6 +72,7 @@ type DBService struct {
 	db.Notification
 	db.Relationship
 	db.Report
+	db.Rule
 	db.Search
 	db.Session
 	db.Status
@@ -216,6 +217,10 @@ func NewBunDBService(ctx context.Context, state *state.State) (db.DB, error) {
 			db:    db,
 			state: state,
 		},
+		Rule: &ruleDB{
+			db:    db,
+			state: state,
+		},
 		Search: &searchDB{
 			db:    db,
 			state: state,
diff --git a/internal/db/bundb/bundb_test.go b/internal/db/bundb/bundb_test.go
index 0cdbb5cce..f3640cf59 100644
--- a/internal/db/bundb/bundb_test.go
+++ b/internal/db/bundb/bundb_test.go
@@ -51,6 +51,7 @@ type BunDBStandardTestSuite struct {
 	testListEntries  map[string]*gtsmodel.ListEntry
 	testAccountNotes map[string]*gtsmodel.AccountNote
 	testMarkers      map[string]*gtsmodel.Marker
+	testRules        map[string]*gtsmodel.Rule
 }
 
 func (suite *BunDBStandardTestSuite) SetupSuite() {
@@ -72,6 +73,7 @@ func (suite *BunDBStandardTestSuite) SetupSuite() {
 	suite.testListEntries = testrig.NewTestListEntries()
 	suite.testAccountNotes = testrig.NewTestAccountNotes()
 	suite.testMarkers = testrig.NewTestMarkers()
+	suite.testRules = testrig.NewTestRules()
 }
 
 func (suite *BunDBStandardTestSuite) SetupTest() {
diff --git a/internal/db/bundb/instance.go b/internal/db/bundb/instance.go
index 7f0e92634..6fec3f2fe 100644
--- a/internal/db/bundb/instance.go
+++ b/internal/db/bundb/instance.go
@@ -151,6 +151,16 @@ func (i *instanceDB) getInstance(ctx context.Context, lookup string, dbQuery fun
 			return nil, err
 		}
 
+		if instance.Domain == config.GetHost() {
+			// also populate Rules
+			rules, err := i.state.DB.GetActiveRules(ctx)
+			if err != nil {
+				log.Error(ctx, err)
+			} else {
+				instance.Rules = rules
+			}
+		}
+
 		return &instance, nil
 	}, keyParts...)
 	if err != nil {
diff --git a/internal/db/bundb/migrations/20230815164500_rules_model.go b/internal/db/bundb/migrations/20230815164500_rules_model.go
new file mode 100644
index 000000000..9b202ede9
--- /dev/null
+++ b/internal/db/bundb/migrations/20230815164500_rules_model.go
@@ -0,0 +1,47 @@
+// GoToSocial
+// Copyright (C) GoToSocial Authors admin@gotosocial.org
+// SPDX-License-Identifier: AGPL-3.0-or-later
+//
+// 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 migrations
+
+import (
+	"context"
+
+	gtsmodel "github.com/superseriousbusiness/gotosocial/internal/gtsmodel"
+	"github.com/uptrace/bun"
+)
+
+func init() {
+	up := func(ctx context.Context, db *bun.DB) error {
+		return db.RunInTx(ctx, nil, func(ctx context.Context, tx bun.Tx) error {
+			if _, err := tx.NewCreateTable().Model(&gtsmodel.Rule{}).IfNotExists().Exec(ctx); err != nil {
+				return err
+			}
+
+			return nil
+		})
+	}
+
+	down := func(ctx context.Context, db *bun.DB) error {
+		return db.RunInTx(ctx, nil, func(ctx context.Context, tx bun.Tx) error {
+			return nil
+		})
+	}
+
+	if err := Migrations.Register(up, down); err != nil {
+		panic(err)
+	}
+}
diff --git a/internal/db/bundb/migrations/20230817174700_add_report_rule_ids.go b/internal/db/bundb/migrations/20230817174700_add_report_rule_ids.go
new file mode 100644
index 000000000..a66739e4c
--- /dev/null
+++ b/internal/db/bundb/migrations/20230817174700_add_report_rule_ids.go
@@ -0,0 +1,53 @@
+// GoToSocial
+// Copyright (C) GoToSocial Authors admin@gotosocial.org
+// SPDX-License-Identifier: AGPL-3.0-or-later
+//
+// 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 migrations
+
+import (
+	"context"
+	"strings"
+
+	"github.com/uptrace/bun"
+	"github.com/uptrace/bun/dialect"
+)
+
+func init() {
+	up := func(ctx context.Context, db *bun.DB) error {
+		if db.Dialect().Name() == dialect.SQLite { // sqlite does not have an array type
+			_, err := db.ExecContext(ctx, "ALTER TABLE ? ADD COLUMN ? VARCHAR", bun.Ident("reports"), bun.Ident("rules"))
+			if err != nil && !(strings.Contains(err.Error(), "already exists") || strings.Contains(err.Error(), "duplicate column name") || strings.Contains(err.Error(), "SQLSTATE 42701")) {
+				return err
+			}
+		} else {
+			_, err := db.ExecContext(ctx, "ALTER TABLE ? ADD COLUMN ? VARCHAR[]", bun.Ident("reports"), bun.Ident("rules"))
+			if err != nil && !(strings.Contains(err.Error(), "already exists") || strings.Contains(err.Error(), "duplicate column name") || strings.Contains(err.Error(), "SQLSTATE 42701")) {
+				return err
+			}
+		}
+		return nil
+	}
+
+	down := func(ctx context.Context, db *bun.DB) error {
+		return db.RunInTx(ctx, nil, func(ctx context.Context, tx bun.Tx) error {
+			return nil
+		})
+	}
+
+	if err := Migrations.Register(up, down); err != nil {
+		panic(err)
+	}
+}
diff --git a/internal/db/bundb/report.go b/internal/db/bundb/report.go
index 7c1dd16e7..9e4ba5b29 100644
--- a/internal/db/bundb/report.go
+++ b/internal/db/bundb/report.go
@@ -186,6 +186,19 @@ func (r *reportDB) PopulateReport(ctx context.Context, report *gtsmodel.Report)
 		}
 	}
 
+	if l := len(report.RuleIDs); l > 0 && l != len(report.Rules) {
+		// Report target rules not set, fetch from the database.
+
+		for _, v := range report.RuleIDs {
+			rule, err := r.state.DB.GetRuleByID(ctx, v)
+			if err != nil {
+				errs.Appendf("error populating report rules: %w", err)
+			} else {
+				report.Rules = append(report.Rules, rule)
+			}
+		}
+	}
+
 	if report.ActionTakenByAccountID != "" &&
 		report.ActionTakenByAccount == nil {
 		// Report action account is not set, fetch from the database.
diff --git a/internal/db/bundb/rule.go b/internal/db/bundb/rule.go
new file mode 100644
index 000000000..79825923b
--- /dev/null
+++ b/internal/db/bundb/rule.go
@@ -0,0 +1,149 @@
+// GoToSocial
+// Copyright (C) GoToSocial Authors admin@gotosocial.org
+// SPDX-License-Identifier: AGPL-3.0-or-later
+//
+// 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 bundb
+
+import (
+	"context"
+	"errors"
+	"time"
+
+	"github.com/superseriousbusiness/gotosocial/internal/config"
+	"github.com/superseriousbusiness/gotosocial/internal/db"
+	"github.com/superseriousbusiness/gotosocial/internal/gtsmodel"
+	"github.com/superseriousbusiness/gotosocial/internal/log"
+	"github.com/superseriousbusiness/gotosocial/internal/state"
+	"github.com/superseriousbusiness/gotosocial/internal/util"
+	"github.com/uptrace/bun"
+)
+
+type ruleDB struct {
+	db    *DB
+	state *state.State
+}
+
+func (r *ruleDB) GetRuleByID(ctx context.Context, id string) (*gtsmodel.Rule, error) {
+	var rule gtsmodel.Rule
+
+	q := r.db.
+		NewSelect().
+		Model(&rule).
+		Where("? = ?", bun.Ident("rule.id"), id)
+
+	if err := q.Scan(ctx); err != nil {
+		return nil, err
+	}
+
+	return &rule, nil
+}
+
+func (r *ruleDB) GetRulesByIDs(ctx context.Context, ids []string) ([]*gtsmodel.Rule, error) {
+	rules := make([]*gtsmodel.Rule, 0, len(ids))
+
+	for _, id := range ids {
+		// Attempt to fetch status from DB.
+		rule, err := r.GetRuleByID(ctx, id)
+		if err != nil {
+			log.Errorf(ctx, "error getting rule %q: %v", id, err)
+			continue
+		}
+
+		// Append status to return slice.
+		rules = append(rules, rule)
+	}
+
+	return rules, nil
+}
+
+func (r *ruleDB) GetActiveRules(ctx context.Context) ([]gtsmodel.Rule, error) {
+	rules := make([]gtsmodel.Rule, 0)
+
+	q := r.db.
+		NewSelect().
+		Model(&rules).
+		// Ignore deleted (ie., inactive) rules.
+		Where("? = ?", bun.Ident("rule.deleted"), false).
+		Order("rule.order ASC")
+
+	if err := q.Scan(ctx); err != nil {
+		return nil, err
+	}
+
+	return rules, nil
+}
+
+func (r *ruleDB) PutRule(ctx context.Context, rule *gtsmodel.Rule) error {
+	var lastRuleOrder uint
+
+	// Select highest existing rule order.
+	err := r.db.
+		NewSelect().
+		TableExpr("? AS ?", bun.Ident("rules"), bun.Ident("rule")).
+		Column("rule.order").
+		Order("rule.order DESC").
+		Limit(1).
+		Scan(ctx, &lastRuleOrder)
+
+	switch {
+	case errors.Is(err, db.ErrNoEntries):
+		// No rules set yet, index from 0.
+		rule.Order = util.Ptr(uint(0))
+
+	case err != nil:
+		// Real db error.
+		return err
+
+	default:
+		// No error means previous rule(s)
+		// existed. New rule order should
+		// be 1 higher than previous rule.
+		rule.Order = func() *uint {
+			o := lastRuleOrder + 1
+			return &o
+		}()
+	}
+
+	if _, err := r.db.
+		NewInsert().
+		Model(rule).
+		Exec(ctx); err != nil {
+		return err
+	}
+
+	// invalidate cached local instance response, so it gets updated with the new rules
+	r.state.Caches.GTS.Instance().Invalidate("Domain", config.GetHost())
+
+	return nil
+}
+
+func (r *ruleDB) UpdateRule(ctx context.Context, rule *gtsmodel.Rule) (*gtsmodel.Rule, error) {
+	// Update the rule's last-updated
+	rule.UpdatedAt = time.Now()
+
+	if _, err := r.db.
+		NewUpdate().
+		Model(rule).
+		WherePK().
+		Exec(ctx); err != nil {
+		return nil, err
+	}
+
+	// invalidate cached local instance response, so it gets updated with the new rules
+	r.state.Caches.GTS.Instance().Invalidate("Domain", config.GetHost())
+
+	return rule, nil
+}
diff --git a/internal/db/bundb/rule_test.go b/internal/db/bundb/rule_test.go
new file mode 100644
index 000000000..822f92fca
--- /dev/null
+++ b/internal/db/bundb/rule_test.go
@@ -0,0 +1,122 @@
+// GoToSocial
+// Copyright (C) GoToSocial Authors admin@gotosocial.org
+// SPDX-License-Identifier: AGPL-3.0-or-later
+//
+// 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 bundb_test
+
+import (
+	"context"
+	"testing"
+
+	"github.com/stretchr/testify/suite"
+	"github.com/superseriousbusiness/gotosocial/internal/db"
+	"github.com/superseriousbusiness/gotosocial/internal/gtsmodel"
+	"github.com/superseriousbusiness/gotosocial/internal/id"
+)
+
+type RuleTestSuite struct {
+	BunDBStandardTestSuite
+}
+
+func (suite *RuleTestSuite) TestPutRuleWithExisting() {
+	r := &gtsmodel.Rule{
+		ID:   id.NewULID(),
+		Text: "Pee pee poo poo",
+	}
+
+	if err := suite.state.DB.PutRule(context.Background(), r); err != nil {
+		suite.FailNow(err.Error())
+	}
+
+	suite.Equal(uint(len(suite.testRules)), *r.Order)
+}
+
+func (suite *RuleTestSuite) TestPutRuleNoExisting() {
+	var (
+		ctx      = context.Background()
+		whereAny = []db.Where{{Key: "id", Value: "", Not: true}}
+	)
+
+	// Wipe all existing rules from the DB.
+	if err := suite.state.DB.DeleteWhere(
+		ctx,
+		whereAny,
+		&[]*gtsmodel.Rule{},
+	); err != nil {
+		suite.FailNow(err.Error())
+	}
+
+	r := &gtsmodel.Rule{
+		ID:   id.NewULID(),
+		Text: "Pee pee poo poo",
+	}
+
+	if err := suite.state.DB.PutRule(ctx, r); err != nil {
+		suite.FailNow(err.Error())
+	}
+
+	// New rule is now only rule.
+	suite.EqualValues(uint(0), *r.Order)
+}
+
+func (suite *RuleTestSuite) TestGetRuleByID() {
+	rule, err := suite.state.DB.GetRuleByID(
+		context.Background(),
+		suite.testRules["rule1"].ID,
+	)
+	if err != nil {
+		suite.FailNow(err.Error())
+	}
+
+	suite.NotNil(rule)
+}
+
+func (suite *RuleTestSuite) TestGetRulesByID() {
+	ruleIDs := make([]string, 0, len(suite.testRules))
+	for _, rule := range suite.testRules {
+		ruleIDs = append(ruleIDs, rule.ID)
+	}
+
+	rules, err := suite.state.DB.GetRulesByIDs(
+		context.Background(),
+		ruleIDs,
+	)
+	if err != nil {
+		suite.FailNow(err.Error())
+	}
+
+	suite.Len(rules, len(suite.testRules))
+}
+
+func (suite *RuleTestSuite) TestGetActiveRules() {
+	var activeRules int
+	for _, rule := range suite.testRules {
+		if !*rule.Deleted {
+			activeRules++
+		}
+	}
+
+	rules, err := suite.state.DB.GetActiveRules(context.Background())
+	if err != nil {
+		suite.FailNow(err.Error())
+	}
+
+	suite.Len(rules, activeRules)
+}
+
+func TestRuleTestSuite(t *testing.T) {
+	suite.Run(t, new(RuleTestSuite))
+}
diff --git a/internal/db/db.go b/internal/db/db.go
index 567551c73..056d03e23 100644
--- a/internal/db/db.go
+++ b/internal/db/db.go
@@ -38,6 +38,7 @@ type DB interface {
 	Notification
 	Relationship
 	Report
+	Rule
 	Search
 	Session
 	Status
diff --git a/internal/db/rule.go b/internal/db/rule.go
new file mode 100644
index 000000000..651b8bced
--- /dev/null
+++ b/internal/db/rule.go
@@ -0,0 +1,42 @@
+// GoToSocial
+// Copyright (C) GoToSocial Authors admin@gotosocial.org
+// SPDX-License-Identifier: AGPL-3.0-or-later
+//
+// 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 db
+
+import (
+	"context"
+
+	"github.com/superseriousbusiness/gotosocial/internal/gtsmodel"
+)
+
+// Rule handles getting/creation/deletion/updating of instance rules.
+type Rule interface {
+	// GetRuleByID gets one rule by its db id.
+	GetRuleByID(ctx context.Context, id string) (*gtsmodel.Rule, error)
+
+	// GetRulesByIDs gets multiple rules by their db idd.
+	GetRulesByIDs(ctx context.Context, ids []string) ([]*gtsmodel.Rule, error)
+
+	// GetRules gets all active (not deleted) rules.
+	GetActiveRules(ctx context.Context) ([]gtsmodel.Rule, error)
+
+	// PutRule puts the given rule in the database.
+	PutRule(ctx context.Context, rule *gtsmodel.Rule) error
+
+	// UpdateRule updates one rule by its db id.
+	UpdateRule(ctx context.Context, rule *gtsmodel.Rule) (*gtsmodel.Rule, error)
+}