[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, 12 insertions, 1 deletions

diff --git a/internal/typeutils/internaltofrontend_test.go b/internal/typeutils/internaltofrontend_test.go
index 005abf4eb..1ca0840a5 100644
--- a/internal/typeutils/internaltofrontend_test.go
+++ b/internal/typeutils/internaltofrontend_test.go
@@ -21,6 +21,7 @@ import (
 	"bytes"
 	"context"
 	"encoding/json"
+	"strings"
 	"testing"
 
 	"github.com/stretchr/testify/suite"
@@ -2061,6 +2062,13 @@ func (suite *InternalToFrontendTestSuite) TestInstanceV2ToFrontend() {
 	b, err := json.MarshalIndent(instance, "", "  ")
 	suite.NoError(err)
 
+	// The VAPID public key changes from run to run.
+	vapidKeyPair, err := suite.db.GetVAPIDKeyPair(ctx)
+	if err != nil {
+		suite.FailNow(err.Error())
+	}
+	s := strings.Replace(string(b), vapidKeyPair.Public, "VAPID_PUBLIC_KEY_PLACEHOLDER", 1)
+
 	suite.Equal(`{
   "domain": "localhost:8080",
   "account_domain": "localhost:8080",
@@ -2140,6 +2148,9 @@ func (suite *InternalToFrontendTestSuite) TestInstanceV2ToFrontend() {
     },
     "emojis": {
       "emoji_size_limit": 51200
+    },
+    "vapid": {
+      "public_key": "VAPID_PUBLIC_KEY_PLACEHOLDER"
     }
   },
   "registrations": {
@@ -2184,7 +2195,7 @@ func (suite *InternalToFrontendTestSuite) TestInstanceV2ToFrontend() {
   "rules": [],
   "terms": "\u003cp\u003eThis is where a list of terms and conditions might go.\u003c/p\u003e\u003cp\u003eFor example:\u003c/p\u003e\u003cp\u003eIf you want to sign up on this instance, you oughta know that we:\u003c/p\u003e\u003col\u003e\u003cli\u003eWill sell your data to whoever offers.\u003c/li\u003e\u003cli\u003eSecure the server with password \u003ccode\u003epassword\u003c/code\u003e wherever possible.\u003c/li\u003e\u003c/ol\u003e",
   "terms_text": "This is where a list of terms and conditions might go.\n\nFor example:\n\nIf you want to sign up on this instance, you oughta know that we:\n\n1. Will sell your data to whoever offers.\n2. Secure the server with password `+"`"+`password`+"`"+` wherever possible."
-}`, string(b))
+}`, s)
 }
 
 func (suite *InternalToFrontendTestSuite) TestEmojiToFrontend() {