[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

1 files changed, 232 insertions, 0 deletions

diff --git a/internal/api/client/push/pushsubscriptionput.go b/internal/api/client/push/pushsubscriptionput.go
new file mode 100644
index 000000000..06575f4ee
--- /dev/null
+++ b/internal/api/client/push/pushsubscriptionput.go
@@ -0,0 +1,232 @@
+// 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 push
+
+import (
+	"net/http"
+
+	"github.com/gin-gonic/gin"
+	apimodel "github.com/superseriousbusiness/gotosocial/internal/api/model"
+	apiutil "github.com/superseriousbusiness/gotosocial/internal/api/util"
+	"github.com/superseriousbusiness/gotosocial/internal/gtserror"
+	"github.com/superseriousbusiness/gotosocial/internal/oauth"
+)
+
+// PushSubscriptionPUTHandler swagger:operation PUT /api/v1/push/subscription pushSubscriptionPut
+//
+// Update the Web Push subscription for the current access token.
+// Only which notifications you receive can be updated.
+//
+//	---
+//	tags:
+//	- push
+//
+//	consumes:
+//	- application/json
+//	- application/x-www-form-urlencoded
+//
+//	produces:
+//	- application/json
+//
+//	parameters:
+//	-
+//		name: data[alerts][follow]
+//		in: formData
+//		type: boolean
+//		default: false
+//		description: Receive a push notification when someone has followed you?
+//	-
+//		name: data[alerts][follow_request]
+//		in: formData
+//		type: boolean
+//		default: false
+//		description: Receive a push notification when someone has requested to follow you?
+//	-
+//		name: data[alerts][favourite]
+//		in: formData
+//		type: boolean
+//		default: false
+//		description: Receive a push notification when a status you created has been favourited by someone else?
+//	-
+//		name: data[alerts][mention]
+//		in: formData
+//		type: boolean
+//		default: false
+//		description: Receive a push notification when someone else has mentioned you in a status?
+//	-
+//		name: data[alerts][reblog]
+//		in: formData
+//		type: boolean
+//		default: false
+//		description: Receive a push notification when a status you created has been boosted by someone else?
+//	-
+//		name: data[alerts][poll]
+//		in: formData
+//		type: boolean
+//		default: false
+//		description: Receive a push notification when a poll you voted in or created has ended?
+//	-
+//		name: data[alerts][status]
+//		in: formData
+//		type: boolean
+//		default: false
+//		description: Receive a push notification when a subscribed account posts a status?
+//	-
+//		name: data[alerts][update]
+//		in: formData
+//		type: boolean
+//		default: false
+//		description: Receive a push notification when a status you interacted with has been edited?
+//	-
+//		name: data[alerts][admin.sign_up]
+//		in: formData
+//		type: boolean
+//		default: false
+//		description: Receive a push notification when a new user has signed up?
+//	-
+//		name: data[alerts][admin.report]
+//		in: formData
+//		type: boolean
+//		default: false
+//		description: Receive a push notification when a new report has been filed?
+//	-
+//		name: data[alerts][pending.favourite]
+//		in: formData
+//		type: boolean
+//		default: false
+//		description: Receive a push notification when a fave is pending?
+//	-
+//		name: data[alerts][pending.reply]
+//		in: formData
+//		type: boolean
+//		default: false
+//		description: Receive a push notification when a reply is pending?
+//	-
+//		name: data[alerts][pending.reblog]
+//		in: formData
+//		type: boolean
+//		default: false
+//		description: Receive a push notification when a boost is pending?
+//
+//	security:
+//	- OAuth2 Bearer:
+//		- push
+//
+//	responses:
+//		'200':
+//			description: Web Push subscription for current access token.
+//			schema:
+//				"$ref": "#/definitions/webPushSubscription"
+//		'400':
+//			description: bad request
+//		'401':
+//			description: unauthorized
+//		'403':
+//			description: forbidden
+//		'404':
+//			description: This access token doesn't have an associated subscription.
+//		'406':
+//			description: not acceptable
+//		'500':
+//			description: internal server error
+func (m *Module) PushSubscriptionPUTHandler(c *gin.Context) {
+	authed, err := oauth.Authed(c, true, true, true, true)
+	if err != nil {
+		apiutil.ErrorHandler(c, gtserror.NewErrorUnauthorized(err, err.Error()), m.processor.InstanceGetV1)
+		return
+	}
+
+	if authed.Account.IsMoving() {
+		apiutil.ForbiddenAfterMove(c)
+		return
+	}
+
+	if _, err := apiutil.NegotiateAccept(c, apiutil.JSONAcceptHeaders...); err != nil {
+		apiutil.ErrorHandler(c, gtserror.NewErrorNotAcceptable(err, err.Error()), m.processor.InstanceGetV1)
+		return
+	}
+
+	form := &apimodel.WebPushSubscriptionUpdateRequest{}
+	if err := c.ShouldBind(form); err != nil {
+		apiutil.ErrorHandler(c, gtserror.NewErrorBadRequest(err, err.Error()), m.processor.InstanceGetV1)
+		return
+	}
+
+	if err := validateNormalizeUpdate(form); err != nil {
+		apiutil.ErrorHandler(c, gtserror.NewErrorUnprocessableEntity(err, err.Error()), m.processor.InstanceGetV1)
+		return
+	}
+
+	apiSubscription, errWithCode := m.processor.Push().Update(c, authed.Token.GetAccess(), form)
+	if errWithCode != nil {
+		apiutil.ErrorHandler(c, errWithCode, m.processor.InstanceGetV1)
+		return
+	}
+
+	apiutil.JSON(c, http.StatusOK, apiSubscription)
+}
+
+// validateNormalizeUpdate copies form fields to their canonical JSON equivalents.
+func validateNormalizeUpdate(request *apimodel.WebPushSubscriptionUpdateRequest) error {
+	if request.Data == nil {
+		request.Data = &apimodel.WebPushSubscriptionRequestData{}
+	}
+
+	if request.Data.Alerts == nil {
+		request.Data.Alerts = &apimodel.WebPushSubscriptionAlerts{}
+	}
+
+	if request.DataAlertsFollow != nil {
+		request.Data.Alerts.Follow = *request.DataAlertsFollow
+	}
+	if request.DataAlertsFollowRequest != nil {
+		request.Data.Alerts.FollowRequest = *request.DataAlertsFollowRequest
+	}
+	if request.DataAlertsMention != nil {
+		request.Data.Alerts.Mention = *request.DataAlertsMention
+	}
+	if request.DataAlertsReblog != nil {
+		request.Data.Alerts.Reblog = *request.DataAlertsReblog
+	}
+	if request.DataAlertsPoll != nil {
+		request.Data.Alerts.Poll = *request.DataAlertsPoll
+	}
+	if request.DataAlertsStatus != nil {
+		request.Data.Alerts.Status = *request.DataAlertsStatus
+	}
+	if request.DataAlertsUpdate != nil {
+		request.Data.Alerts.Update = *request.DataAlertsUpdate
+	}
+	if request.DataAlertsAdminSignup != nil {
+		request.Data.Alerts.AdminSignup = *request.DataAlertsAdminSignup
+	}
+	if request.DataAlertsAdminReport != nil {
+		request.Data.Alerts.AdminReport = *request.DataAlertsAdminReport
+	}
+	if request.DataAlertsPendingFavourite != nil {
+		request.Data.Alerts.PendingFavourite = *request.DataAlertsPendingFavourite
+	}
+	if request.DataAlertsPendingReply != nil {
+		request.Data.Alerts.PendingReply = *request.DataAlertsPendingReply
+	}
+	if request.DataAlertsPendingReblog != nil {
+		request.Data.Alerts.Reblog = *request.DataAlertsPendingReblog
+	}
+
+	return nil
+}