[feature] Push notifications (#3587)

* Update push subscription API model to be Mastodon 4.0 compatible

* Add webpush-go dependency

# Conflicts:
#	go.sum

* Single-row table for storing instance's VAPID key pair

* Generate VAPID key pair during startup

* Add VAPID public key to instance info API

* Return VAPID public key when registering an app

* Store Web Push subscriptions in DB

* Add Web Push sender (similar to email sender)

* Add no-op push senders to most processor tests

* Test Web Push notifications from workers

* Delete Web Push subscriptions when account is deleted

* Implement push subscription API

* Linter fixes

* Update Swagger

* Fix enum to int migration

* Fix GetVAPIDKeyPair

* Create web push subscriptions table with indexes

* Log Web Push server error messages

* Send instance URL as Web Push JWT subject

* Accept any 2xx code as a success

* Fix malformed VAPID sub claim

* Use packed notification flags

* Remove unused date columns

* Add notification type for update notifications

Not used yet

* Make GetVAPIDKeyPair idempotent

and remove PutVAPIDKeyPair

* Post-rebase fixes

* go mod tidy

* Special-case 400 errors other than 408/429

Most client errors should remove the subscription.

* Improve titles, trim body to reasonable length

* Disallow cleartext HTTP for Web Push servers

* Fix lint

* Remove redundant index on unique column

Also removes redundant unique and notnull tags on ID column since these are implied by pk

* Make realsender.go more readable

* Use Tobi's style for wrapping errors

* Restore treating all 5xx codes as temporary problems

* Always load target account settings

* Stub `policy` and `standard`

* webpush.Sender: take type converter as ctor param

* Move webpush.MockSender and noopSender into testrig

6 files changed, 118 insertions, 3 deletions

diff --git a/testrig/db.go b/testrig/db.go
index e53e9c9f0..d33a63f12 100644
--- a/testrig/db.go
+++ b/testrig/db.go
@@ -61,6 +61,8 @@ var testModels = []interface{}{
 	&gtsmodel.ThreadToStatus{},
 	&gtsmodel.User{},
 	&gtsmodel.UserMute{},
+	&gtsmodel.VAPIDKeyPair{},
+	&gtsmodel.WebPushSubscription{},
 	&gtsmodel.Emoji{},
 	&gtsmodel.Instance{},
 	&gtsmodel.Notification{},
@@ -348,6 +350,12 @@ func StandardDBSetup(db db.DB, accounts map[string]*gtsmodel.Account) {
 		}
 	}
 
+	for _, v := range NewTestWebPushSubscriptions() {
+		if err := db.Put(ctx, v); err != nil {
+			log.Panic(nil, err)
+		}
+	}
+
 	for _, v := range NewTestInteractionRequests() {
 		if err := db.Put(ctx, v); err != nil {
 			log.Panic(ctx, err)
@@ -368,6 +376,11 @@ func StandardDBSetup(db db.DB, accounts map[string]*gtsmodel.Account) {
 		log.Panic(ctx, err)
 	}
 
+	// Generates and stores a VAPID key pair as a side effect.
+	if _, err := db.GetVAPIDKeyPair(ctx); err != nil {
+		log.Panic(nil, err)
+	}
+
 	log.Debug(ctx, "testing db setup complete")
 }
 
diff --git a/testrig/processor.go b/testrig/processor.go
index bbb8d9d1d..478e2124c 100644
--- a/testrig/processor.go
+++ b/testrig/processor.go
@@ -28,6 +28,7 @@ import (
 	"github.com/superseriousbusiness/gotosocial/internal/state"
 	"github.com/superseriousbusiness/gotosocial/internal/subscriptions"
 	"github.com/superseriousbusiness/gotosocial/internal/typeutils"
+	"github.com/superseriousbusiness/gotosocial/internal/webpush"
 )
 
 // NewTestProcessor returns a Processor suitable for testing purposes.
@@ -37,6 +38,7 @@ func NewTestProcessor(
 	state *state.State,
 	federator *federation.Federator,
 	emailSender email.Sender,
+	webPushSender webpush.Sender,
 	mediaManager *media.Manager,
 ) *processing.Processor {
 
@@ -53,6 +55,7 @@ func NewTestProcessor(
 		mediaManager,
 		state,
 		emailSender,
+		webPushSender,
 		visibility.NewFilter(state),
 		interaction.NewFilter(state),
 	)
diff --git a/testrig/testmodels.go b/testrig/testmodels.go
index da4202eed..9a54aba70 100644
--- a/testrig/testmodels.go
+++ b/testrig/testmodels.go
@@ -2585,7 +2585,7 @@ func NewTestNotifications() map[string]*gtsmodel.Notification {
 	return map[string]*gtsmodel.Notification{
 		"local_account_1_like": {
 			ID:               "01F8Q0ANPTWW10DAKTX7BRPBJP",
-			NotificationType: gtsmodel.NotificationFave,
+			NotificationType: gtsmodel.NotificationFavourite,
 			CreatedAt:        TimeMustParse("2022-05-14T13:21:09+02:00"),
 			TargetAccountID:  "01F8MH1H7YV1Z7D2C8K2730QBF",
 			OriginAccountID:  "01F8MH17FWEB39HZJ76B6VXSKF",
@@ -2594,7 +2594,7 @@ func NewTestNotifications() map[string]*gtsmodel.Notification {
 		},
 		"local_account_2_like": {
 			ID:               "01GTS6PRPXJYZBPFFQ56PP0XR8",
-			NotificationType: gtsmodel.NotificationFave,
+			NotificationType: gtsmodel.NotificationFavourite,
 			CreatedAt:        TimeMustParse("2022-01-13T12:45:01+02:00"),
 			TargetAccountID:  "01F8MH17FWEB39HZJ76B6VXSKF",
 			OriginAccountID:  "01F8MH5NBDF2MV7CTC4Q5128HF",
@@ -2603,7 +2603,7 @@ func NewTestNotifications() map[string]*gtsmodel.Notification {
 		},
 		"new_signup": {
 			ID:               "01HTM9TETMB3YQCBKZ7KD4KV02",
-			NotificationType: gtsmodel.NotificationSignup,
+			NotificationType: gtsmodel.NotificationAdminSignup,
 			CreatedAt:        TimeMustParse("2022-06-04T13:12:00Z"),
 			TargetAccountID:  "01F8MH17FWEB39HZJ76B6VXSKF",
 			OriginAccountID:  "01F8MH0BBE4FHXPH513MBVFHB0",
@@ -3586,6 +3586,34 @@ func NewTestUserMutes() map[string]*gtsmodel.UserMute {
 	return map[string]*gtsmodel.UserMute{}
 }
 
+func NewTestWebPushSubscriptions() map[string]*gtsmodel.WebPushSubscription {
+	return map[string]*gtsmodel.WebPushSubscription{
+		"local_account_1_token_1": {
+			ID:        "01G65Z755AFWAKHE12NY0CQ9FH",
+			AccountID: "01F8MH1H7YV1Z7D2C8K2730QBF",
+			TokenID:   "01F8MGTQW4DKTDF8SW5CT9HYGA",
+			Endpoint:  "https://example.test/push",
+			Auth:      "cgna/fzrYLDQyPf5hD7IsA==",
+			P256dh:    "BMYVItYVOX+AHBdtA62Q0i6c+F7MV2Gia3aoDr8mvHkuPBNIOuTLDfmFcnBqoZcQk6BtLcIONbxhHpy2R+mYIUY=",
+			NotificationFlags: gtsmodel.WebPushSubscriptionNotificationFlagsFromSlice([]gtsmodel.NotificationType{
+				gtsmodel.NotificationFollow,
+				gtsmodel.NotificationFollowRequest,
+				gtsmodel.NotificationFavourite,
+				gtsmodel.NotificationMention,
+				gtsmodel.NotificationReblog,
+				gtsmodel.NotificationPoll,
+				gtsmodel.NotificationStatus,
+				gtsmodel.NotificationUpdate,
+				gtsmodel.NotificationAdminSignup,
+				gtsmodel.NotificationAdminReport,
+				gtsmodel.NotificationPendingFave,
+				gtsmodel.NotificationPendingReply,
+				gtsmodel.NotificationPendingReblog,
+			}),
+		},
+	}
+}
+
 func NewTestInteractionRequests() map[string]*gtsmodel.InteractionRequest {
 	return map[string]*gtsmodel.InteractionRequest{
 		"admin_account_reply_turtle": {
diff --git a/testrig/teststructs.go b/testrig/teststructs.go
index 58986bffa..7d5c3caab 100644
--- a/testrig/teststructs.go
+++ b/testrig/teststructs.go
@@ -47,6 +47,7 @@ type TestStructs struct {
 	HTTPClient          *MockHTTPClient
 	TypeConverter       *typeutils.Converter
 	EmailSender         email.Sender
+	WebPushSender       *WebPushMockSender
 	TransportController transport.Controller
 }
 
@@ -83,6 +84,7 @@ func SetupTestStructs(
 	federator := NewTestFederator(&state, transportController, mediaManager)
 	oauthServer := NewTestOauthServer(db)
 	emailSender := NewEmailSender(rTemplatePath, nil)
+	webPushSender := NewWebPushMockSender()
 
 	common := common.New(
 		&state,
@@ -101,6 +103,7 @@ func SetupTestStructs(
 		mediaManager,
 		&state,
 		emailSender,
+		webPushSender,
 		visFilter,
 		intFilter,
 	)
@@ -117,6 +120,7 @@ func SetupTestStructs(
 		HTTPClient:          httpClient,
 		TypeConverter:       typeconverter,
 		EmailSender:         emailSender,
+		WebPushSender:       webPushSender,
 		TransportController: transportController,
 	}
 }
diff --git a/testrig/util.go b/testrig/util.go
index 957553d79..a4bf1bea4 100644
--- a/testrig/util.go
+++ b/testrig/util.go
@@ -84,6 +84,7 @@ func StartWorkers(state *state.State, processor *workers.Processor) {
 	state.Workers.Federator.Start(1)
 	state.Workers.Dereference.Start(1)
 	state.Workers.Processing.Start(1)
+	state.Workers.WebPush.Start(1)
 }
 
 func StopWorkers(state *state.State) {
@@ -92,6 +93,7 @@ func StopWorkers(state *state.State) {
 	state.Workers.Federator.Stop()
 	state.Workers.Dereference.Stop()
 	state.Workers.Processing.Stop()
+	state.Workers.WebPush.Stop()
 }
 
 func StartTimelines(state *state.State, visFilter *visibility.Filter, converter *typeutils.Converter) {
diff --git a/testrig/webpush.go b/testrig/webpush.go
new file mode 100644
index 000000000..4cd5d7a81
--- /dev/null
+++ b/testrig/webpush.go
@@ -0,0 +1,65 @@
+// 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 testrig
+
+import (
+	"context"
+
+	"github.com/superseriousbusiness/gotosocial/internal/filter/usermute"
+	"github.com/superseriousbusiness/gotosocial/internal/gtsmodel"
+	"github.com/superseriousbusiness/gotosocial/internal/webpush"
+)
+
+// WebPushMockSender collects a map of notifications sent to each account ID.
+type WebPushMockSender struct {
+	Sent map[string][]*gtsmodel.Notification
+}
+
+// NewWebPushMockSender creates a mock sender that can record sent Web Push notifications for test expectations.
+func NewWebPushMockSender() *WebPushMockSender {
+	return &WebPushMockSender{
+		Sent: map[string][]*gtsmodel.Notification{},
+	}
+}
+
+func (m *WebPushMockSender) Send(
+	ctx context.Context,
+	notification *gtsmodel.Notification,
+	filters []*gtsmodel.Filter,
+	mutes *usermute.CompiledUserMuteList,
+) error {
+	m.Sent[notification.TargetAccountID] = append(m.Sent[notification.TargetAccountID], notification)
+	return nil
+}
+
+// noopSender drops anything sent to it.
+type noopWebPushSender struct{}
+
+// NewNoopWebPushSender creates a no-op sender that does nothing.
+func NewNoopWebPushSender() webpush.Sender {
+	return &noopWebPushSender{}
+}
+
+func (n *noopWebPushSender) Send(
+	ctx context.Context,
+	notification *gtsmodel.Notification,
+	filters []*gtsmodel.Filter,
+	mutes *usermute.CompiledUserMuteList,
+) error {
+	return nil
+}