[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, 10 insertions, 0 deletions

diff --git a/internal/processing/processor.go b/internal/processing/processor.go
index 8dabfba96..0bba23089 100644
--- a/internal/processing/processor.go
+++ b/internal/processing/processor.go
@@ -39,6 +39,7 @@ import (
 	"github.com/superseriousbusiness/gotosocial/internal/processing/markers"
 	"github.com/superseriousbusiness/gotosocial/internal/processing/media"
 	"github.com/superseriousbusiness/gotosocial/internal/processing/polls"
+	"github.com/superseriousbusiness/gotosocial/internal/processing/push"
 	"github.com/superseriousbusiness/gotosocial/internal/processing/report"
 	"github.com/superseriousbusiness/gotosocial/internal/processing/search"
 	"github.com/superseriousbusiness/gotosocial/internal/processing/status"
@@ -51,6 +52,7 @@ import (
 	"github.com/superseriousbusiness/gotosocial/internal/subscriptions"
 	"github.com/superseriousbusiness/gotosocial/internal/text"
 	"github.com/superseriousbusiness/gotosocial/internal/typeutils"
+	"github.com/superseriousbusiness/gotosocial/internal/webpush"
 )
 
 // Processor groups together processing functions and
@@ -88,6 +90,7 @@ type Processor struct {
 	markers             markers.Processor
 	media               media.Processor
 	polls               polls.Processor
+	push                push.Processor
 	report              report.Processor
 	search              search.Processor
 	status              status.Processor
@@ -146,6 +149,10 @@ func (p *Processor) Polls() *polls.Processor {
 	return &p.polls
 }
 
+func (p *Processor) Push() *push.Processor {
+	return &p.push
+}
+
 func (p *Processor) Report() *report.Processor {
 	return &p.report
 }
@@ -188,6 +195,7 @@ func NewProcessor(
 	mediaManager *mm.Manager,
 	state *state.State,
 	emailSender email.Sender,
+	webPushSender webpush.Sender,
 	visFilter *visibility.Filter,
 	intFilter *interaction.Filter,
 ) *Processor {
@@ -221,6 +229,7 @@ func NewProcessor(
 	processor.list = list.New(state, converter)
 	processor.markers = markers.New(state, converter)
 	processor.polls = polls.New(&common, state, converter)
+	processor.push = push.New(state, converter)
 	processor.report = report.New(state, converter)
 	processor.tags = tags.New(state, converter)
 	processor.timeline = timeline.New(state, converter, visFilter)
@@ -241,6 +250,7 @@ func NewProcessor(
 		converter,
 		visFilter,
 		emailSender,
+		webPushSender,
 		&processor.account,
 		&processor.media,
 		&processor.stream,