Merge branch 'main' into logging

2024-06-26 10:01:09 +12:00 · 2022-05-31 23:39:11 -04:00 · 2022-05-31 23:39:11 -04:00 · a04cf5fcb6
parent dc0e699fb5 9202d85532
commit a04cf5fcb6
20 changed files with 917 additions and 715 deletions
--- a/.github/workflows/build.yaml
+++ b/.github/workflows/build.yaml
@ -0,0 +1,39 @@
+name: build
+on: [push, pull_request]
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    steps:
+      -
+        name: Install Go
+        uses: actions/setup-go@v2
+        with:
+          go-version: '1.18.x'
+      -
+        name: Install node
+        uses: actions/setup-node@v2
+        with:
+          node-version: '16'
+      -
+        name: Checkout code
+        uses: actions/checkout@v2
+      -
+        name: Cache Go and npm modules
+        uses: actions/cache@v3
+        with:
+          path: |
+            ~/go/pkg/mod
+            ~/go/bin
+            ~/.npm
+            web/node_modules
+          key: ${{ runner.os }}-ntfy-${{ hashFiles('**/go.sum', '**/package.lock') }}
+          restore-keys: ${{ runner.os }}-ntfy-
+      -
+        name: Install dependencies
+        run: make build-deps-ubuntu
+      -
+        name: Build all the things
+        run: make build
+      -
+        name: Print build results and checksums
+        run: make cli-build-results
--- a/.github/workflows/codeql-analysis.yml
+++ b/.github/workflows/codeql-analysis.yml
@ -1,72 +0,0 @@
-# For most projects, this workflow file will not need changing; you simply need
-# to commit it to your repository.
-#
-# You may wish to alter this file to override the set of languages analyzed,
-# or to provide custom queries or build logic.
-#
-# ******** NOTE ********
-# We have attempted to detect the languages in your repository. Please check
-# the `language` matrix defined below to confirm you have the correct set of
-# supported CodeQL languages.
-#
-name: "CodeQL"
-
-on:
-  push:
-    branches: [ main ]
-  pull_request:
-    # The branches below must be a subset of the branches above
-    branches: [ main ]
-  schedule:
-    - cron: '21 10 * * 5'
-
-jobs:
-  analyze:
-    name: Analyze
-    runs-on: ubuntu-latest
-    permissions:
-      actions: read
-      contents: read
-      security-events: write
-
-    strategy:
-      fail-fast: false
-      matrix:
-        language: [ 'go', 'javascript' ]
-        # CodeQL supports [ 'cpp', 'csharp', 'go', 'java', 'javascript', 'python', 'ruby' ]
-        # Learn more about CodeQL language support at https://aka.ms/codeql-docs/language-support
-
-    steps:
-    - name: Checkout repository
-      uses: actions/checkout@v3
-
-    # Initializes the CodeQL tools for scanning.
-    - name: Initialize CodeQL
-      uses: github/codeql-action/init@v2
-      with:
-        languages: ${{ matrix.language }}
-        # If you wish to specify custom queries, you can do so here or in a config file.
-        # By default, queries listed here will override any specified in a config file.
-        # Prefix the list here with "+" to use these queries and those in the config file.
-        
-        # Details on CodeQL's query packs refer to : https://docs.github.com/en/code-security/code-scanning/automatically-scanning-your-code-for-vulnerabilities-and-errors/configuring-code-scanning#using-queries-in-ql-packs
-        # queries: security-extended,security-and-quality
-
-        
-    # Autobuild attempts to build any compiled languages  (C/C++, C#, or Java).
-    # If this step fails, then you should remove it and run the build manually (see below)
-    - name: Autobuild
-      uses: github/codeql-action/autobuild@v2
-
-    # ℹ️ Command-line programs to run using the OS shell.
-    # 📚 See https://docs.github.com/en/actions/using-workflows/workflow-syntax-for-github-actions#jobsjob_idstepsrun
-
-    #   If the Autobuild fails above, remove it and uncomment the following three lines. 
-    #   modify them (or add more) to build your code if your project, please refer to the EXAMPLE below for guidance.
-
-    # - run: |
-    #   echo "Run, Build Application using script"
-    #   ./location_of_script_within_repo/buildscript.sh
-
-    - name: Perform CodeQL Analysis
-      uses: github/codeql-action/analyze@v2
--- a/.github/workflows/release.yaml
+++ b/.github/workflows/release.yaml
@ -0,0 +1,50 @@
+name: release
+on:
+  push:
+    tags:
+      - 'v[0-9]+.[0-9]+.[0-9]+'
+jobs:
+  release:
+    runs-on: ubuntu-latest
+    steps:
+      -
+        name: Install Go
+        uses: actions/setup-go@v2
+        with:
+          go-version: '1.18.x'
+      -
+        name: Install node
+        uses: actions/setup-node@v2
+        with:
+          node-version: '16'
+      -
+        name: Checkout code
+        uses: actions/checkout@v2
+      -
+        name: Cache Go and npm modules
+        uses: actions/cache@v3
+        with:
+          path: |
+            ~/go/pkg/mod
+            ~/go/bin
+            ~/.npm
+            web/node_modules
+          key: ${{ runner.os }}-ntfy-${{ hashFiles('**/go.sum', '**/package.lock') }}
+          restore-keys: ${{ runner.os }}-ntfy-
+      -
+        name: Docker login
+        uses: docker/login-action@v2
+        with:
+          username: ${{ github.repository_owner }}
+          password: ${{ secrets.DOCKER_HUB_TOKEN }}
+      -
+        name: Install dependencies
+        run: make build-deps-ubuntu
+      -
+        name: Build and publish
+        run: make release
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+      -
+        name: Print build results and checksums
+        run: make cli-build-results
--- a/.github/workflows/test.yaml
+++ b/.github/workflows/test.yaml
@ -3,26 +3,46 @@ on: [push, pull_request]
 jobs:
  test:
    runs-on: ubuntu-latest
-    steps:
-      - name: Install Go
+    steps: 
+      -
+        name: Install Go
        uses: actions/setup-go@v2
        with:
-          go-version: '1.17.x'
-      - name: Install node
+          go-version: '1.18.x'
+      -
+        name: Install node
        uses: actions/setup-node@v2
        with:
          node-version: '16'
-      - name: Checkout code
+      -
+        name: Checkout code
        uses: actions/checkout@v2
-      - name: Install dependencies
-        run: sudo apt update && sudo apt install -y python3-pip curl
-      - name: Build docs (required for tests)
+      -
+        name: Cache Go and npm modules
+        uses: actions/cache@v3
+        with:
+          path: |
+            ~/go/pkg/mod
+            ~/go/bin
+            ~/.npm
+            web/node_modules
+          key: ${{ runner.os }}-ntfy-${{ hashFiles('**/go.sum', '**/package.lock') }}
+          restore-keys: ${{ runner.os }}-ntfy-
+      -
+        name: Install dependencies
+        run: make build-deps-ubuntu
+      -
+        name: Build docs (required for tests)
        run: make docs
-      - name: Build web app (required for tests)
+      -
+        name: Build web app (required for tests)
        run: make web
-      - name: Run tests, formatting, vetting and linting
+      -
+        name: Run tests, formatting, vetting and linting
        run: make check
-      - name: Run coverage
+      -
+        name: Run coverage
        run: make coverage
-      - name: Upload coverage to codecov.io
+      -
+        name: Upload coverage to codecov.io
        run: make coverage-upload
--- a/.goreleaser.yml
+++ b/.goreleaser.yml
@ -157,6 +157,7 @@ universal_binaries:
  -
    id: ntfy_darwin_all
    replace: true
+    name_template: ntfy
 checksum:
  name_template: 'checksums.txt'
 snapshot:
--- a/52
+++ b/52
@ -79,6 +79,18 @@ build: web docs cli
 update: web-deps-update cli-deps-update docs-deps-update
 	docker pull alpine

+# Ubuntu-specific
+
+build-deps-ubuntu:
+	sudo apt update
+	sudo apt install -y \
+		curl \
+		gcc-aarch64-linux-gnu \
+		gcc-arm-linux-gnueabi \
+		upx \
+		jq
+	which pip3 || sudo apt install -y python3-pip
+
 # Documentation

 docs: docs-deps docs-build
@ -114,28 +126,29 @@ web-deps:
 web-deps-update:
 	cd web && npm update

+
 # Main server/client build

 cli: cli-deps
-	goreleaser build --snapshot --rm-dist --debug
+	goreleaser build --snapshot --rm-dist

 cli-linux-amd64: cli-deps-static-sites
-	goreleaser build --snapshot --rm-dist --debug --id ntfy_linux_amd64
+	goreleaser build --snapshot --rm-dist --id ntfy_linux_amd64

 cli-linux-armv6: cli-deps-static-sites cli-deps-gcc-armv6-armv7
-	goreleaser build --snapshot --rm-dist --debug --id ntfy_linux_armv6
+	goreleaser build --snapshot --rm-dist --id ntfy_linux_armv6

 cli-linux-armv7: cli-deps-static-sites cli-deps-gcc-armv6-armv7
-	goreleaser build --snapshot --rm-dist --debug --id ntfy_linux_armv7
+	goreleaser build --snapshot --rm-dist --id ntfy_linux_armv7

 cli-linux-arm64: cli-deps-static-sites cli-deps-gcc-arm64
-	goreleaser build --snapshot --rm-dist --debug --id ntfy_linux_arm64
+	goreleaser build --snapshot --rm-dist --id ntfy_linux_arm64

 cli-windows-amd64: cli-deps-static-sites
-	goreleaser build --snapshot --rm-dist --debug --id ntfy_windows_amd64
+	goreleaser build --snapshot --rm-dist --id ntfy_windows_amd64

 cli-darwin-all: cli-deps-static-sites
-	goreleaser build --snapshot --rm-dist --debug --id ntfy_darwin_all
+	goreleaser build --snapshot --rm-dist --id ntfy_darwin_all

 cli-linux-server: cli-deps-static-sites
 	# This is a target to build the CLI (including the server) manually.
@ -177,6 +190,7 @@ cli-deps-static-sites:

 cli-deps-all:
 	which upx || { echo "ERROR: upx not installed. On Ubuntu, run: apt install upx"; exit 1; }
+	go install github.com/goreleaser/goreleaser@latest

 cli-deps-gcc-armv6-armv7:
 	which arm-linux-gnueabi-gcc || { echo "ERROR: ARMv6/ARMv7 cross compiler not installed. On Ubuntu, run: apt install gcc-arm-linux-gnueabi"; exit 1; }
@ -187,6 +201,18 @@ cli-deps-gcc-arm64:
 cli-deps-update:
 	go get -u
 	go install honnef.co/go/tools/cmd/staticcheck@latest
+	go install golang.org/x/lint/golint@latest
+	go install github.com/goreleaser/goreleaser@latest
+
+cli-build-results:
+	cat dist/config.yaml
+	[ -f dist/artifacts.json ] && cat dist/artifacts.json | jq . || true
+	[ -f dist/metadata.json ] && cat dist/metadata.json | jq . || true
+	[ -f dist/checksums.txt ] && cat dist/checksums.txt || true
+	find dist -maxdepth 2 -type f \
+		\( -name '*.deb' -or -name '*.rpm' -or -name '*.zip' -or -name '*.tar.gz' -or -name 'ntfy' \) \
+		-and -not -path 'dist/goreleaserdocker*' \
+		-exec sha256sum {} \;

 # Test/check targets

@ -238,13 +264,13 @@ staticcheck: .PHONY

 # Releasing targets

-release: clean update cli-deps release-check-tags docs web check
-	goreleaser release --rm-dist --debug
+release: clean update cli-deps release-checks docs web check
+	goreleaser release --rm-dist

 release-snapshot: clean update cli-deps docs web check
-	goreleaser release --snapshot --skip-publish --rm-dist --debug
+	goreleaser release --snapshot --skip-publish --rm-dist

-release-check-tags:
+release-checks:
 	$(eval LATEST_TAG := $(shell git describe --abbrev=0 --tags | cut -c2-))
 	if ! grep -q $(LATEST_TAG) docs/install.md; then\
 	 	echo "ERROR: Must update docs/install.md with latest tag first.";\
@ -254,6 +280,10 @@ release-check-tags:
 		echo "ERROR: Must update docs/releases.md with latest tag first.";\
 		exit 1;\
 	fi
+	if [ -n "$(shell git status -s)" ]; then\
+	  echo "ERROR: Git repository is in an unclean state.";\
+	  exit 1;\
+	fi


 # Installing targets
--- a/docs/releases.md
+++ b/docs/releases.md
@ -4,13 +4,39 @@ and the [ntfy Android app](https://github.com/binwiederhier/ntfy-android/release

 <!--

-## ntfy iOS app v1.1 (UNRELEASED)
+## ntfy Android app v1.14.0 (UNRELEASED)
+
+**Additional translations:**
+
+* Italian (thanks to [@Genio2003](https://hosted.weblate.org/user/Genio2003/))
+
+
+## ntfy server v1.25.0 (UNRELEASED)
+
+**Bugs**:
+
+* Respect Firebase "quota exceeded" response for topics, block Firebase publishing for user for 10min ([#289](https://github.com/binwiederhier/ntfy/issues/289))
+
+**Maintenance:**
+
+* Upgrade Firebase Admin SDK to 4.x ([#274](https://github.com/binwiederhier/ntfy/issues/274))
+* CI: Build from pipeline instead of locally ([#36](https://github.com/binwiederhier/ntfy/issues/36))
+
+**Documentation**:
+
+* [Examples](examples.md) for [Home Assistant](https://www.home-assistant.io/) ([#282](https://github.com/binwiederhier/ntfy/pull/282), thanks to [@poblabs](https://github.com/poblabs))
+
+-->
+
+
+## ntfy iOS app v1.1
+Released May 31, 2022

 In this release of the iOS app, we add message priorities (mapped to iOS interruption levels), tags and emojis,
 action buttons to open websites or perform HTTP requests (in the notification and the detail view), a custom click
 action when the notification is tapped, and various other fixes.

-It also adds support for self-hosted servers (albeit not supporting auth yet). The selfhosted server needs to be 
+It also adds support for self-hosted servers (albeit not supporting auth yet). The self-hosted server needs to be
 configured to forward poll requests to upstream ntfy.sh for push notifications to work (see [iOS push notifications](https://ntfy.sh/docs/config/#ios-instant-notifications)
 for details).

@ -29,26 +55,6 @@ for details).

 * iOS UI not always updating properly ([#267](https://github.com/binwiederhier/ntfy/issues/267))

-
-## ntfy Android app v1.14.0 (UNRELEASED)
-
-**Additional translations:**
-
-* Italian (thanks to [@Genio2003](https://hosted.weblate.org/user/Genio2003/))
-
-
-## ntfy server v1.25.0 (UNRELEASED)
-
-**Maintenance:**
-
-* Upgrade Firebase Admin SDK to 4.x ([#274](https://github.com/binwiederhier/ntfy/issues/274))
-
-**Documentation**:
-
-* [Examples](examples.md) for [Home Assistant](https://www.home-assistant.io/) ([#282](https://github.com/binwiederhier/ntfy/pull/282), thanks to [@poblabs](https://github.com/poblabs))
-
-->
-
 ## ntfy server v1.24.0
 Released May 28, 2022

--- a/server/config.go
+++ b/server/config.go
@ -6,15 +6,16 @@ import (

 // Defines default config settings (excluding limits, see below)
 const (
-	DefaultListenHTTP                = ":80"
-	DefaultCacheDuration             = 12 * time.Hour
-	DefaultKeepaliveInterval         = 45 * time.Second // Not too frequently to save battery (Android read timeout used to be 77s!)
-	DefaultManagerInterval           = time.Minute
-	DefaultAtSenderInterval          = 10 * time.Second
-	DefaultMinDelay                  = 10 * time.Second
-	DefaultMaxDelay                  = 3 * 24 * time.Hour
-	DefaultFirebaseKeepaliveInterval = 3 * time.Hour    // ~control topic (Android), not too frequently to save battery
-	DefaultFirebasePollInterval      = 20 * time.Minute // ~poll topic (iOS), max. 2-3 times per hour (see docs)
+	DefaultListenHTTP                           = ":80"
+	DefaultCacheDuration                        = 12 * time.Hour
+	DefaultKeepaliveInterval                    = 45 * time.Second // Not too frequently to save battery (Android read timeout used to be 77s!)
+	DefaultManagerInterval                      = time.Minute
+	DefaultDelayedSenderInterval                = 10 * time.Second
+	DefaultMinDelay                             = 10 * time.Second
+	DefaultMaxDelay                             = 3 * 24 * time.Hour
+	DefaultFirebaseKeepaliveInterval            = 3 * time.Hour    // ~control topic (Android), not too frequently to save battery
+	DefaultFirebasePollInterval                 = 20 * time.Minute // ~poll topic (iOS), max. 2-3 times per hour (see docs)
+	DefaultFirebaseQuotaExceededPenaltyDuration = 10 * time.Minute // Time that over-users are locked out of Firebase if it returns "quota exceeded"
 )

 // Defines all global and per-visitor limits
@ -66,9 +67,10 @@ type Config struct {
 	KeepaliveInterval                    time.Duration
 	ManagerInterval                      time.Duration
 	WebRootIsApp                         bool
-	AtSenderInterval                     time.Duration
+	DelayedSenderInterval                time.Duration
 	FirebaseKeepaliveInterval            time.Duration
 	FirebasePollInterval                 time.Duration
+	FirebaseQuotaExceededPenaltyDuration time.Duration
 	UpstreamBaseURL                      string
 	SMTPSenderAddr                       string
 	SMTPSenderUser                       string
@ -118,9 +120,10 @@ func NewConfig() *Config {
 		MessageLimit:                         DefaultMessageLengthLimit,
 		MinDelay:                             DefaultMinDelay,
 		MaxDelay:                             DefaultMaxDelay,
-		AtSenderInterval:                     DefaultAtSenderInterval,
+		DelayedSenderInterval:                DefaultDelayedSenderInterval,
 		FirebaseKeepaliveInterval:            DefaultFirebaseKeepaliveInterval,
 		FirebasePollInterval:                 DefaultFirebasePollInterval,
+		FirebaseQuotaExceededPenaltyDuration: DefaultFirebaseQuotaExceededPenaltyDuration,
 		TotalTopicLimit:                      DefaultTotalTopicLimit,
 		VisitorSubscriptionLimit:             DefaultVisitorSubscriptionLimit,
 		VisitorAttachmentTotalSizeLimit:      DefaultVisitorAttachmentTotalSizeLimit,
--- a/server/message_cache.go
+++ b/server/message_cache.go
@ -36,7 +36,7 @@ const (
 			attachment_size INT NOT NULL,
 			attachment_expires INT NOT NULL,
 			attachment_url TEXT NOT NULL,
-			attachment_owner TEXT NOT NULL,
+			sender TEXT NOT NULL,
 			encoding TEXT NOT NULL,
 			published INT NOT NULL
 		);
@ -45,37 +45,37 @@ const (
 		COMMIT;
 	`
 	insertMessageQuery = `
-		INSERT INTO messages (mid, time, topic, message, title, priority, tags, click, actions, attachment_name, attachment_type, attachment_size, attachment_expires, attachment_url, attachment_owner, encoding, published) 
+		INSERT INTO messages (mid, time, topic, message, title, priority, tags, click, actions, attachment_name, attachment_type, attachment_size, attachment_expires, attachment_url, sender, encoding, published) 
 		VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?)
 	`
 	pruneMessagesQuery           = `DELETE FROM messages WHERE time < ? AND published = 1`
 	selectRowIDFromMessageID     = `SELECT id FROM messages WHERE topic = ? AND mid = ?`
 	selectMessagesSinceTimeQuery = `
-		SELECT mid, time, topic, message, title, priority, tags, click, actions, attachment_name, attachment_type, attachment_size, attachment_expires, attachment_url, attachment_owner, encoding
+		SELECT mid, time, topic, message, title, priority, tags, click, actions, attachment_name, attachment_type, attachment_size, attachment_expires, attachment_url, sender, encoding
 		FROM messages 
 		WHERE topic = ? AND time >= ? AND published = 1
 		ORDER BY time, id
 	`
 	selectMessagesSinceTimeIncludeScheduledQuery = `
-		SELECT mid, time, topic, message, title, priority, tags, click, actions, attachment_name, attachment_type, attachment_size, attachment_expires, attachment_url, attachment_owner, encoding
+		SELECT mid, time, topic, message, title, priority, tags, click, actions, attachment_name, attachment_type, attachment_size, attachment_expires, attachment_url, sender, encoding
 		FROM messages 
 		WHERE topic = ? AND time >= ?
 		ORDER BY time, id
 	`
 	selectMessagesSinceIDQuery = `
-		SELECT mid, time, topic, message, title, priority, tags, click, actions, attachment_name, attachment_type, attachment_size, attachment_expires, attachment_url, attachment_owner, encoding
+		SELECT mid, time, topic, message, title, priority, tags, click, actions, attachment_name, attachment_type, attachment_size, attachment_expires, attachment_url, sender, encoding
 		FROM messages 
 		WHERE topic = ? AND id > ? AND published = 1 
 		ORDER BY time, id
 	`
 	selectMessagesSinceIDIncludeScheduledQuery = `
-		SELECT mid, time, topic, message, title, priority, tags, click, actions, attachment_name, attachment_type, attachment_size, attachment_expires, attachment_url, attachment_owner, encoding
+		SELECT mid, time, topic, message, title, priority, tags, click, actions, attachment_name, attachment_type, attachment_size, attachment_expires, attachment_url, sender, encoding
 		FROM messages 
 		WHERE topic = ? AND (id > ? OR published = 0)
 		ORDER BY time, id
 	`
 	selectMessagesDueQuery = `
-		SELECT mid, time, topic, message, title, priority, tags, click, actions, attachment_name, attachment_type, attachment_size, attachment_expires, attachment_url, attachment_owner, encoding
+		SELECT mid, time, topic, message, title, priority, tags, click, actions, attachment_name, attachment_type, attachment_size, attachment_expires, attachment_url, sender, encoding
 		FROM messages 
 		WHERE time <= ? AND published = 0
 		ORDER BY time, id
@ -84,13 +84,13 @@ const (
 	selectMessagesCountQuery        = `SELECT COUNT(*) FROM messages`
 	selectMessageCountForTopicQuery = `SELECT COUNT(*) FROM messages WHERE topic = ?`
 	selectTopicsQuery               = `SELECT topic FROM messages GROUP BY topic`
-	selectAttachmentsSizeQuery      = `SELECT IFNULL(SUM(attachment_size), 0) FROM messages WHERE attachment_owner = ? AND attachment_expires >= ?`
+	selectAttachmentsSizeQuery      = `SELECT IFNULL(SUM(attachment_size), 0) FROM messages WHERE sender = ? AND attachment_expires >= ?`
 	selectAttachmentsExpiredQuery   = `SELECT mid FROM messages WHERE attachment_expires > 0 AND attachment_expires < ?`
 )

 // Schema management queries
 const (
-	currentSchemaVersion          = 6
+	currentSchemaVersion          = 7
 	createSchemaVersionTableQuery = `
 		CREATE TABLE IF NOT EXISTS schemaVersion (
 			id INT PRIMARY KEY,
@ -173,6 +173,11 @@ const (
 	migrate5To6AlterMessagesTableQuery = `
 		ALTER TABLE messages ADD COLUMN actions TEXT NOT NULL DEFAULT('');
 	`
+
+	// 6 -> 7
+	migrate6To7AlterMessagesTableQuery = `
+		ALTER TABLE messages RENAME COLUMN attachment_owner TO sender;
+	`
 )

 type messageCache struct {
@ -225,7 +230,7 @@ func (c *messageCache) AddMessage(m *message) error {
 	}
 	published := m.Time <= time.Now().Unix()
 	tags := strings.Join(m.Tags, ",")
-	var attachmentName, attachmentType, attachmentURL, attachmentOwner string
+	var attachmentName, attachmentType, attachmentURL string
 	var attachmentSize, attachmentExpires int64
 	if m.Attachment != nil {
 		attachmentName = m.Attachment.Name
@ -233,7 +238,6 @@ func (c *messageCache) AddMessage(m *message) error {
 		attachmentSize = m.Attachment.Size
 		attachmentExpires = m.Attachment.Expires
 		attachmentURL = m.Attachment.URL
-		attachmentOwner = m.Attachment.Owner
 	}
 	var actionsStr string
 	if len(m.Actions) > 0 {
@ -259,7 +263,7 @@ func (c *messageCache) AddMessage(m *message) error {
 		attachmentSize,
 		attachmentExpires,
 		attachmentURL,
-		attachmentOwner,
+		m.Sender,
 		m.Encoding,
 		published,
 	)
@ -371,8 +375,8 @@ func (c *messageCache) Prune(olderThan time.Time) error {
 	return err
 }

-func (c *messageCache) AttachmentBytesUsed(owner string) (int64, error) {
-	rows, err := c.db.Query(selectAttachmentsSizeQuery, owner, time.Now().Unix())
+func (c *messageCache) AttachmentBytesUsed(sender string) (int64, error) {
+	rows, err := c.db.Query(selectAttachmentsSizeQuery, sender, time.Now().Unix())
 	if err != nil {
 		return 0, err
 	}
@ -415,7 +419,7 @@ func readMessages(rows *sql.Rows) ([]*message, error) {
 	for rows.Next() {
 		var timestamp, attachmentSize, attachmentExpires int64
 		var priority int
-		var id, topic, msg, title, tagsStr, click, actionsStr, attachmentName, attachmentType, attachmentURL, attachmentOwner, encoding string
+		var id, topic, msg, title, tagsStr, click, actionsStr, attachmentName, attachmentType, attachmentURL, sender, encoding string
 		err := rows.Scan(
 			&id,
 			&timestamp,
@ -431,7 +435,7 @@ func readMessages(rows *sql.Rows) ([]*message, error) {
 			&attachmentSize,
 			&attachmentExpires,
 			&attachmentURL,
-			&attachmentOwner,
+			&sender,
 			&encoding,
 		)
 		if err != nil {
@ -455,7 +459,6 @@ func readMessages(rows *sql.Rows) ([]*message, error) {
 				Size:    attachmentSize,
 				Expires: attachmentExpires,
 				URL:     attachmentURL,
-				Owner:   attachmentOwner,
 			}
 		}
 		messages = append(messages, &message{
@ -470,6 +473,7 @@ func readMessages(rows *sql.Rows) ([]*message, error) {
 			Click:      click,
 			Actions:    actions,
 			Attachment: att,
+			Sender:     sender,
 			Encoding:   encoding,
 		})
 	}
@ -516,6 +520,8 @@ func setupCacheDB(db *sql.DB) error {
 		return migrateFrom4(db)
 	} else if schemaVersion == 5 {
 		return migrateFrom5(db)
+	} else if schemaVersion == 6 {
+		return migrateFrom6(db)
 	}
 	return fmt.Errorf("unexpected schema version found: %d", schemaVersion)
 }
@ -599,5 +605,16 @@ func migrateFrom5(db *sql.DB) error {
 	if _, err := db.Exec(updateSchemaVersion, 6); err != nil {
 		return err
 	}
+	return migrateFrom6(db)
+}
+
+func migrateFrom6(db *sql.DB) error {
+	log.Print("Migrating cache database schema: from 6 to 7")
+	if _, err := db.Exec(migrate6To7AlterMessagesTableQuery); err != nil {
+		return err
+	}
+	if _, err := db.Exec(updateSchemaVersion, 7); err != nil {
+		return err
+	}
 	return nil // Update this when a new version is added
 }
--- a/server/message_cache_test.go
+++ b/server/message_cache_test.go
@ -281,39 +281,39 @@ func testCacheAttachments(t *testing.T, c *messageCache) {
 	expires1 := time.Now().Add(-4 * time.Hour).Unix()
 	m := newDefaultMessage("mytopic", "flower for you")
 	m.ID = "m1"
+	m.Sender = "1.2.3.4"
 	m.Attachment = &attachment{
 		Name:    "flower.jpg",
 		Type:    "image/jpeg",
 		Size:    5000,
 		Expires: expires1,
 		URL:     "https://ntfy.sh/file/AbDeFgJhal.jpg",
-		Owner:   "1.2.3.4",
 	}
 	require.Nil(t, c.AddMessage(m))

 	expires2 := time.Now().Add(2 * time.Hour).Unix() // Future
 	m = newDefaultMessage("mytopic", "sending you a car")
 	m.ID = "m2"
+	m.Sender = "1.2.3.4"
 	m.Attachment = &attachment{
 		Name:    "car.jpg",
 		Type:    "image/jpeg",
 		Size:    10000,
 		Expires: expires2,
 		URL:     "https://ntfy.sh/file/aCaRURL.jpg",
-		Owner:   "1.2.3.4",
 	}
 	require.Nil(t, c.AddMessage(m))

 	expires3 := time.Now().Add(1 * time.Hour).Unix() // Future
 	m = newDefaultMessage("another-topic", "sending you another car")
 	m.ID = "m3"
+	m.Sender = "1.2.3.4"
 	m.Attachment = &attachment{
 		Name:    "another-car.jpg",
 		Type:    "image/jpeg",
 		Size:    20000,
 		Expires: expires3,
 		URL:     "https://ntfy.sh/file/zakaDHFW.jpg",
-		Owner:   "1.2.3.4",
 	}
 	require.Nil(t, c.AddMessage(m))

@ -327,7 +327,7 @@ func testCacheAttachments(t *testing.T, c *messageCache) {
 	require.Equal(t, int64(5000), messages[0].Attachment.Size)
 	require.Equal(t, expires1, messages[0].Attachment.Expires)
 	require.Equal(t, "https://ntfy.sh/file/AbDeFgJhal.jpg", messages[0].Attachment.URL)
-	require.Equal(t, "1.2.3.4", messages[0].Attachment.Owner)
+	require.Equal(t, "1.2.3.4", messages[0].Sender)

 	require.Equal(t, "sending you a car", messages[1].Message)
 	require.Equal(t, "car.jpg", messages[1].Attachment.Name)
@ -335,7 +335,7 @@ func testCacheAttachments(t *testing.T, c *messageCache) {
 	require.Equal(t, int64(10000), messages[1].Attachment.Size)
 	require.Equal(t, expires2, messages[1].Attachment.Expires)
 	require.Equal(t, "https://ntfy.sh/file/aCaRURL.jpg", messages[1].Attachment.URL)
-	require.Equal(t, "1.2.3.4", messages[1].Attachment.Owner)
+	require.Equal(t, "1.2.3.4", messages[1].Sender)

 	size, err := c.AttachmentBytesUsed("1.2.3.4")
 	require.Nil(t, err)
--- a/server/server.go
+++ b/server/server.go
@ -7,13 +7,11 @@ import (
 	"embed"
 	"encoding/base64"
 	"encoding/json"
-	"errors"
 	"fmt"
 	"heckel.io/ntfy/log"
 	"io"
 	"net"
 	"net/http"
-	"net/http/httptest"
 	"net/url"
 	"os"
 	"path"
@ -34,22 +32,22 @@ import (

 // Server is the main server, providing the UI and API for ntfy
 type Server struct {
-	config       *Config
-	httpServer   *http.Server
-	httpsServer  *http.Server
-	unixListener net.Listener
-	smtpServer   *smtp.Server
-	smtpBackend  *smtpBackend
-	topics       map[string]*topic
-	visitors     map[string]*visitor
-	firebase     subscriber
-	mailer       mailer
-	messages     int64
-	auth         auth.Auther
-	messageCache *messageCache
-	fileCache    *fileCache
-	closeChan    chan bool
-	mu           sync.Mutex
+	config         *Config
+	httpServer     *http.Server
+	httpsServer    *http.Server
+	unixListener   net.Listener
+	smtpServer     *smtp.Server
+	smtpBackend    *smtpBackend
+	topics         map[string]*topic
+	visitors       map[string]*visitor
+	firebaseClient *firebaseClient
+	mailer         mailer
+	messages       int64
+	auth           auth.Auther
+	messageCache   *messageCache
+	fileCache      *fileCache
+	closeChan      chan bool
+	mu             sync.Mutex
 }

 // handleFunc extends the normal http.HandlerFunc to be able to easily return errors
@ -136,23 +134,23 @@ func New(conf *Config) (*Server, error) {
 			return nil, err
 		}
 	}
-	var firebaseSubscriber subscriber
+	var firebaseClient *firebaseClient
 	if conf.FirebaseKeyFile != "" {
-		var err error
-		firebaseSubscriber, err = createFirebaseSubscriber(conf.FirebaseKeyFile, auther)
+		sender, err := newFirebaseSender(conf.FirebaseKeyFile)
 		if err != nil {
 			return nil, err
 		}
+		firebaseClient = newFirebaseClient(sender, auther)
 	}
 	return &Server{
-		config:       conf,
-		messageCache: messageCache,
-		fileCache:    fileCache,
-		firebase:     firebaseSubscriber,
-		mailer:       mailer,
-		topics:       topics,
-		auth:         auther,
-		visitors:     make(map[string]*visitor),
+		config:         conf,
+		messageCache:   messageCache,
+		fileCache:      fileCache,
+		firebaseClient: firebaseClient,
+		mailer:         mailer,
+		topics:         topics,
+		auth:           auther,
+		visitors:       make(map[string]*visitor),
 	}, nil
 }

@ -221,7 +219,7 @@ func (s *Server) Run() error {
 	}
 	s.mu.Unlock()
 	go s.runManager()
-	go s.runDelaySender()
+	go s.runDelayedSender()
 	go s.runFirebaseKeepaliver()

 	return <-errChan
@ -439,17 +437,17 @@ func (s *Server) handlePublish(w http.ResponseWriter, r *http.Request, v *visito
 	log.Debug("[%s] %s %s: ev=%s, body=%d bytes, delayed=%t, fb=%t, cache=%t, up=%t, email=%s",
 		v.ip, r.Method, r.URL.Path, m.Event, len(body.PeekedBytes), delayed, firebase, cache, unifiedpush, email)
 	if !delayed {
-		if err := t.Publish(m); err != nil {
+		if err := t.Publish(v, m); err != nil {
 			return err
 		}
 	}
-	if s.firebase != nil && firebase && !delayed {
+	if s.firebaseClient != nil && firebase && !delayed {
 		go s.sendToFirebase(v, m)
 	}
 	if s.mailer != nil && email != "" && !delayed {
 		go s.sendEmail(v, m, email)
 	}
-	if s.config.UpstreamBaseURL != "" {
+	if s.config.UpstreamBaseURL != "" && !delayed {
 		go s.forwardPollRequest(v, m)
 	}
 	if cache {
@ -469,7 +467,7 @@ func (s *Server) handlePublish(w http.ResponseWriter, r *http.Request, v *visito
 }

 func (s *Server) sendToFirebase(v *visitor, m *message) {
-	if err := s.firebase(m); err != nil {
+	if err := s.firebaseClient.Send(v, m); err != nil {
 		log.Warn("[%s] FB - Unable to publish to Firebase: %v", v.ip, err.Error())
 	}
 }
@ -490,7 +488,10 @@ func (s *Server) forwardPollRequest(v *visitor, m *message) {
 		return
 	}
 	req.Header.Set("X-Poll-ID", m.ID)
-	response, err := http.DefaultClient.Do(req)
+	var httpClient = &http.Client{
+		Timeout: time.Second * 10,
+	}
+	response, err := httpClient.Do(req)
 	if err != nil {
 		log.Warn("[%s] FWD - Unable to forward poll request: %v", v.ip, err.Error())
 		return
@ -572,6 +573,7 @@ func (s *Server) parsePublishParams(r *http.Request, v *visitor, m *message) (ca
 			return false, false, "", false, errHTTPBadRequestDelayTooLarge
 		}
 		m.Time = delay.Unix()
+		m.Sender = v.ip // Important for rate limiting
 	}
 	actionsStr := readParam(r, "x-actions", "actions", "action")
 	if actionsStr != "" {
@ -667,7 +669,7 @@ func (s *Server) handleBodyAsAttachment(r *http.Request, v *visitor, m *message,
 		m.Attachment = &attachment{}
 	}
 	var ext string
-	m.Attachment.Owner = v.ip // Important for attachment rate limiting
+	m.Sender = v.ip // Important for attachment rate limiting
 	m.Attachment.Expires = time.Now().Add(s.config.AttachmentExpiryDuration).Unix()
 	m.Attachment.Type, ext = util.DetectContentType(body.PeekedBytes, m.Attachment.Name)
 	m.Attachment.URL = fmt.Sprintf("%s/file/%s%s", s.config.BaseURL, m.ID, ext)
@ -735,7 +737,7 @@ func (s *Server) handleSubscribeHTTP(w http.ResponseWriter, r *http.Request, v *
 		return err
 	}
 	var wlock sync.Mutex
-	sub := func(msg *message) error {
+	sub := func(v *visitor, msg *message) error {
 		if !filters.Pass(msg) {
 			return nil
 		}
@ -756,7 +758,7 @@ func (s *Server) handleSubscribeHTTP(w http.ResponseWriter, r *http.Request, v *
 	w.Header().Set("Access-Control-Allow-Origin", "*")            // CORS, allow cross-origin requests
 	w.Header().Set("Content-Type", contentType+"; charset=utf-8") // Android/Volley client needs charset!
 	if poll {
-		return s.sendOldMessages(topics, since, scheduled, sub)
+		return s.sendOldMessages(topics, since, scheduled, v, sub)
 	}
 	subscriberIDs := make([]int, 0)
 	for _, t := range topics {
@ -767,10 +769,10 @@ func (s *Server) handleSubscribeHTTP(w http.ResponseWriter, r *http.Request, v *
 			topics[i].Unsubscribe(subscriberID) // Order!
 		}
 	}()
-	if err := sub(newOpenMessage(topicsStr)); err != nil { // Send out open message
+	if err := sub(v, newOpenMessage(topicsStr)); err != nil { // Send out open message
 		return err
 	}
-	if err := s.sendOldMessages(topics, since, scheduled, sub); err != nil {
+	if err := s.sendOldMessages(topics, since, scheduled, v, sub); err != nil {
 		return err
 	}
 	for {
@ -779,7 +781,7 @@ func (s *Server) handleSubscribeHTTP(w http.ResponseWriter, r *http.Request, v *
 			return nil
 		case <-time.After(s.config.KeepaliveInterval):
 			v.Keepalive()
-			if err := sub(newKeepaliveMessage(topicsStr)); err != nil { // Send keepalive message
+			if err := sub(v, newKeepaliveMessage(topicsStr)); err != nil { // Send keepalive message
 				return err
 			}
 		}
@ -853,7 +855,7 @@ func (s *Server) handleSubscribeWS(w http.ResponseWriter, r *http.Request, v *vi
 			}
 		}
 	})
-	sub := func(msg *message) error {
+	sub := func(v *visitor, msg *message) error {
 		if !filters.Pass(msg) {
 			return nil
 		}
@ -866,7 +868,7 @@ func (s *Server) handleSubscribeWS(w http.ResponseWriter, r *http.Request, v *vi
 	}
 	w.Header().Set("Access-Control-Allow-Origin", "*") // CORS, allow cross-origin requests
 	if poll {
-		return s.sendOldMessages(topics, since, scheduled, sub)
+		return s.sendOldMessages(topics, since, scheduled, v, sub)
 	}
 	subscriberIDs := make([]int, 0)
 	for _, t := range topics {
@ -877,10 +879,10 @@ func (s *Server) handleSubscribeWS(w http.ResponseWriter, r *http.Request, v *vi
 			topics[i].Unsubscribe(subscriberID) // Order!
 		}
 	}()
-	if err := sub(newOpenMessage(topicsStr)); err != nil { // Send out open message
+	if err := sub(v, newOpenMessage(topicsStr)); err != nil { // Send out open message
 		return err
 	}
-	if err := s.sendOldMessages(topics, since, scheduled, sub); err != nil {
+	if err := s.sendOldMessages(topics, since, scheduled, v, sub); err != nil {
 		return err
 	}
 	err = g.Wait()
@ -904,7 +906,7 @@ func parseSubscribeParams(r *http.Request) (poll bool, since sinceMarker, schedu
 	return
 }

-func (s *Server) sendOldMessages(topics []*topic, since sinceMarker, scheduled bool, sub subscriber) error {
+func (s *Server) sendOldMessages(topics []*topic, since sinceMarker, scheduled bool, v *visitor, sub subscriber) error {
 	if since.IsNone() {
 		return nil
 	}
@ -914,7 +916,7 @@ func (s *Server) sendOldMessages(topics []*topic, since sinceMarker, scheduled b
 			return err
 		}
 		for _, m := range messages {
-			if err := sub(m); err != nil {
+			if err := sub(v, m); err != nil {
 				return err
 			}
 		}
@ -1061,23 +1063,7 @@ func (s *Server) updateStatsAndPrune() {
 }

 func (s *Server) runSMTPServer() error {
-	sub := func(m *message) error {
-		url := fmt.Sprintf("%s/%s", s.config.BaseURL, m.Topic)
-		req, err := http.NewRequest("PUT", url, strings.NewReader(m.Message))
-		if err != nil {
-			return err
-		}
-		if m.Title != "" {
-			req.Header.Set("Title", m.Title)
-		}
-		rr := httptest.NewRecorder()
-		s.handle(rr, req)
-		if rr.Code != http.StatusOK {
-			return errors.New("error: " + rr.Body.String())
-		}
-		return nil
-	}
-	s.smtpBackend = newMailBackend(s.config, sub)
+	s.smtpBackend = newMailBackend(s.config, s.handle)
 	s.smtpServer = smtp.NewServer(s.smtpBackend)
 	s.smtpServer.Addr = s.config.SMTPServerListen
 	s.smtpServer.Domain = s.config.SMTPServerDomain
@ -1100,10 +1086,10 @@ func (s *Server) runManager() {
 	}
 }

-func (s *Server) runDelaySender() {
+func (s *Server) runDelayedSender() {
 	for {
 		select {
-		case <-time.After(s.config.AtSenderInterval):
+		case <-time.After(s.config.DelayedSenderInterval):
 			if err := s.sendDelayedMessages(); err != nil {
 				log.Warn("error sending scheduled messages: %s", err.Error())
 			}
@ -1114,19 +1100,16 @@ func (s *Server) runDelaySender() {
 }

 func (s *Server) runFirebaseKeepaliver() {
-	if s.firebase == nil {
+	if s.firebaseClient == nil {
 		return
 	}
+	v := newVisitor(s.config, s.messageCache, "0.0.0.0") // Background process, not a real visitor
 	for {
 		select {
 		case <-time.After(s.config.FirebaseKeepaliveInterval):
-			if err := s.firebase(newKeepaliveMessage(firebaseControlTopic)); err != nil {
-				log.Info("error sending Firebase keepalive message to %s: %s", firebaseControlTopic, err.Error())
-			}
+			s.sendToFirebase(v, newKeepaliveMessage(firebaseControlTopic))
 		case <-time.After(s.config.FirebasePollInterval):
-			if err := s.firebase(newKeepaliveMessage(firebasePollTopic)); err != nil {
-				log.Info("error sending Firebase keepalive message to %s: %s", firebasePollTopic, err.Error())
-			}
+			s.sendToFirebase(v, newKeepaliveMessage(firebasePollTopic))
 		case <-s.closeChan:
 			return
 		}
@ -1134,27 +1117,39 @@ func (s *Server) runFirebaseKeepaliver() {
 }

 func (s *Server) sendDelayedMessages() error {
-	s.mu.Lock()
-	defer s.mu.Unlock()
 	messages, err := s.messageCache.MessagesDue()
 	if err != nil {
 		return err
 	}
 	for _, m := range messages {
-		t, ok := s.topics[m.Topic] // If no subscribers, just mark message as published
-		if ok {
-			if err := t.Publish(m); err != nil {
-				log.Info("unable to publish message %s to topic %s: %v", m.ID, m.Topic, err.Error())
+		v := s.visitorFromIP(m.Sender)
+		if err := s.sendDelayedMessage(v, m); err != nil {
+			log.Warn("error sending delayed message: %s", err.Error())
+		}
+	}
+	return nil
+}
+
+func (s *Server) sendDelayedMessage(v *visitor, m *message) error {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+	t, ok := s.topics[m.Topic] // If no subscribers, just mark message as published
+	if ok {
+		go func() {
+			// We do not rate-limit messages here, since we've rate limited them in the PUT/POST handler
+			if err := t.Publish(v, m); err != nil {
+				log.Warn("unable to publish message %s to topic %s: %v", m.ID, m.Topic, err.Error())
 			}
-		}
-		if s.firebase != nil { // Firebase subscribers may not show up in topics map
-			if err := s.firebase(m); err != nil {
-				log.Info("unable to publish to Firebase: %v", err.Error())
-			}
-		}
-		if err := s.messageCache.MarkPublished(m); err != nil {
-			return err
-		}
+		}()
+	}
+	if s.firebaseClient != nil { // Firebase subscribers may not show up in topics map
+		go s.sendToFirebase(v, m)
+	}
+	if s.config.UpstreamBaseURL != "" {
+		go s.forwardPollRequest(v, m)
+	}
+	if err := s.messageCache.MarkPublished(m); err != nil {
+		return err
 	}
 	return nil
 }
@ -1294,8 +1289,6 @@ func extractUserPass(r *http.Request) (username string, password string, ok bool
 // visitor creates or retrieves a rate.Limiter for the given visitor.
 // This function was taken from https://www.alexedwards.net/blog/how-to-rate-limit-http-requests (MIT).
 func (s *Server) visitor(r *http.Request) *visitor {
-	s.mu.Lock()
-	defer s.mu.Unlock()
 	remoteAddr := r.RemoteAddr
 	ip, _, err := net.SplitHostPort(remoteAddr)
 	if err != nil {
@ -1304,6 +1297,12 @@ func (s *Server) visitor(r *http.Request) *visitor {
 	if s.config.BehindProxy && r.Header.Get("X-Forwarded-For") != "" {
 		ip = r.Header.Get("X-Forwarded-For")
 	}
+	return s.visitorFromIP(ip)
+}
+
+func (s *Server) visitorFromIP(ip string) *visitor {
+	s.mu.Lock()
+	defer s.mu.Unlock()
 	v, exists := s.visitors[ip]
 	if !exists {
 		s.visitors[ip] = newVisitor(s.config, s.messageCache, ip)
--- a/server/server_firebase.go
+++ b/server/server_firebase.go
@ -3,7 +3,9 @@ package server
 import (
 	"context"
 	"encoding/json"
+	"errors"
 	"fmt"
+	"log"
 	"strings"

 	firebase "firebase.google.com/go/v4"
@ -17,25 +19,75 @@ const (
 	fcmApnsBodyMessageLimit = 100
 )

-func createFirebaseSubscriber(credentialsFile string, auther auth.Auther) (subscriber, error) {
+var (
+	errFirebaseQuotaExceeded = errors.New("quota exceeded for Firebase messages to topic")
+)
+
+// firebaseClient is a generic client that formats and sends messages to Firebase.
+// The actual Firebase implementation is implemented in firebaseSenderImpl, to make it testable.
+type firebaseClient struct {
+	sender firebaseSender
+	auther auth.Auther
+}
+
+func newFirebaseClient(sender firebaseSender, auther auth.Auther) *firebaseClient {
+	return &firebaseClient{
+		sender: sender,
+		auther: auther,
+	}
+}
+
+func (c *firebaseClient) Send(v *visitor, m *message) error {
+	if err := v.FirebaseAllowed(); err != nil {
+		return errFirebaseQuotaExceeded
+	}
+	fbm, err := toFirebaseMessage(m, c.auther)
+	if err != nil {
+		return err
+	}
+	err = c.sender.Send(fbm)
+	if err == errFirebaseQuotaExceeded {
+		log.Printf("[%s] FB quota exceeded for topic %s, temporarily denying FB access to visitor", v.ip, m.Topic)
+		v.FirebaseTemporarilyDeny()
+	}
+	return err
+}
+
+// firebaseSender is an interface that represents a client that can send to Firebase Cloud Messaging.
+// In tests, this can be implemented with a mock.
+type firebaseSender interface {
+	// Send sends a message to Firebase, or returns an error. It returns errFirebaseQuotaExceeded
+	// if a rate limit has reached.
+	Send(m *messaging.Message) error
+}
+
+// firebaseSenderImpl is a firebaseSender that actually talks to Firebase
+type firebaseSenderImpl struct {
+	client *messaging.Client
+}
+
+func newFirebaseSender(credentialsFile string) (*firebaseSenderImpl, error) {
 	fb, err := firebase.NewApp(context.Background(), nil, option.WithCredentialsFile(credentialsFile))
 	if err != nil {
 		return nil, err
 	}
-	msg, err := fb.Messaging(context.Background())
+	client, err := fb.Messaging(context.Background())
 	if err != nil {
 		return nil, err
 	}
-	return func(m *message) error {
-		fbm, err := toFirebaseMessage(m, auther)
-		if err != nil {
-			return err
-		}
-		_, err = msg.Send(context.Background(), fbm)
-		return err
+	return &firebaseSenderImpl{
+		client: client,
 	}, nil
 }

+func (c *firebaseSenderImpl) Send(m *messaging.Message) error {
+	_, err := c.client.Send(context.Background(), m)
+	if err != nil && messaging.IsQuotaExceeded(err) {
+		return errFirebaseQuotaExceeded
+	}
+	return err
+}
+
 // toFirebaseMessage converts a message to a Firebase message.
 //
 // Normal messages ("message"):
--- a/server/server_firebase_test.go
+++ b/server/server_firebase_test.go
@ -26,6 +26,25 @@ func (t testAuther) Authorize(_ *auth.User, _ string, _ auth.Permission) error {
 	return errors.New("unauthorized")
 }

+type testFirebaseSender struct {
+	allowed  int
+	messages []*messaging.Message
+}
+
+func newTestFirebaseSender(allowed int) *testFirebaseSender {
+	return &testFirebaseSender{
+		allowed:  allowed,
+		messages: make([]*messaging.Message, 0),
+	}
+}
+func (s *testFirebaseSender) Send(m *messaging.Message) error {
+	if len(s.messages)+1 > s.allowed {
+		return errFirebaseQuotaExceeded
+	}
+	s.messages = append(s.messages, m)
+	return nil
+}
+
 func TestToFirebaseMessage_Keepalive(t *testing.T) {
 	m := newKeepaliveMessage("mytopic")
 	fbm, err := toFirebaseMessage(m, nil)
@ -119,7 +138,6 @@ func TestToFirebaseMessage_Message_Normal_Allowed(t *testing.T) {
 		Size:    12345,
 		Expires: 98765543,
 		URL:     "https://example.com/file.jpg",
-		Owner:   "some-owner",
 	}
 	fbm, err := toFirebaseMessage(m, &testAuther{Allow: true})
 	require.Nil(t, err)
@ -286,3 +304,22 @@ func TestMaybeTruncateFCMMessage_NotTooLong(t *testing.T) {
 	require.Equal(t, len(serializedOrigFCMMessage), len(serializedNotTruncatedFCMMessage))
 	require.Equal(t, "", notTruncatedFCMMessage.Data["truncated"])
 }
+
+func TestToFirebaseSender_Abuse(t *testing.T) {
+	sender := &testFirebaseSender{allowed: 2}
+	client := newFirebaseClient(sender, &testAuther{})
+	visitor := newVisitor(newTestConfig(t), newMemTestCache(t), "1.2.3.4")
+
+	require.Nil(t, client.Send(visitor, &message{Topic: "mytopic"}))
+	require.Equal(t, 1, len(sender.messages))
+
+	require.Nil(t, client.Send(visitor, &message{Topic: "mytopic"}))
+	require.Equal(t, 2, len(sender.messages))
+
+	require.Equal(t, errFirebaseQuotaExceeded, client.Send(visitor, &message{Topic: "mytopic"}))
+	require.Equal(t, 2, len(sender.messages))
+
+	sender.messages = make([]*messaging.Message, 0) // Reset to test that time limit is working
+	require.Equal(t, errFirebaseQuotaExceeded, client.Send(visitor, &message{Topic: "mytopic"}))
+	require.Equal(t, 0, len(sender.messages))
+}
--- a/server/server_test.go
+++ b/server/server_test.go
@ -9,7 +9,6 @@ import (
 	"math/rand"
 	"net/http"
 	"net/http/httptest"
-	"os"
 	"path/filepath"
 	"strings"
 	"sync"
@ -55,6 +54,21 @@ func TestServer_PublishAndPoll(t *testing.T) {
 	require.Equal(t, "my second  message", lines[1]) // \n -> " "
 }

+func TestServer_PublishWithFirebase(t *testing.T) {
+	sender := newTestFirebaseSender(10)
+	s := newTestServer(t, newTestConfig(t))
+	s.firebaseClient = newFirebaseClient(sender, &testAuther{Allow: true})
+
+	response := request(t, s, "PUT", "/mytopic", "my first message", nil)
+	msg1 := toMessage(t, response.Body.String())
+	require.NotEmpty(t, msg1.ID)
+	require.Equal(t, "my first message", msg1.Message)
+	require.Equal(t, 1, len(sender.messages))
+	require.Equal(t, "my first message", sender.messages[0].Data["message"])
+	require.Equal(t, "my first message", sender.messages[0].APNS.Payload.Aps.Alert.Body)
+	require.Equal(t, "my first message", sender.messages[0].APNS.Payload.CustomData["message"])
+}
+
 func TestServer_SubscribeOpenAndKeepalive(t *testing.T) {
 	c := newTestConfig(t)
 	c.KeepaliveInterval = time.Second
@ -264,7 +278,7 @@ func TestServer_PublishNoCache(t *testing.T) {
 func TestServer_PublishAt(t *testing.T) {
 	c := newTestConfig(t)
 	c.MinDelay = time.Second
-	c.AtSenderInterval = 100 * time.Millisecond
+	c.DelayedSenderInterval = 100 * time.Millisecond
 	s := newTestServer(t, c)

 	response := request(t, s, "PUT", "/mytopic", "a message", map[string]string{
@ -283,6 +297,13 @@ func TestServer_PublishAt(t *testing.T) {
 	messages = toMessages(t, response.Body.String())
 	require.Equal(t, 1, len(messages))
 	require.Equal(t, "a message", messages[0].Message)
+	require.Equal(t, "", messages[0].Sender) // Never return the sender!
+
+	messages, err := s.messageCache.Messages("mytopic", sinceAllMessages, true)
+	require.Nil(t, err)
+	require.Equal(t, 1, len(messages))
+	require.Equal(t, "a message", messages[0].Message)
+	require.Equal(t, "9.9.9.9", messages[0].Sender) // It's stored in the DB though!
 }

 func TestServer_PublishAtWithCacheError(t *testing.T) {
@ -454,26 +475,6 @@ func TestServer_PublishMessageInHeaderWithNewlines(t *testing.T) {
 	require.Equal(t, "Line 1\nLine 2", msg.Message) // \\n -> \n !
 }

-func TestServer_PublishFirebase(t *testing.T) {
-	// This is unfortunately not much of a test, since it merely fires the messages towards Firebase,
-	// but cannot re-read them. There is no way from Go to read the messages back, or even get an error back.
-	// I tried everything. I already had written the test, and it increases the code coverage, so I'll leave it ... :shrug: ...
-
-	c := newTestConfig(t)
-	c.FirebaseKeyFile = firebaseServiceAccountFile(t) // May skip the test!
-	s := newTestServer(t, c)
-
-	// Normal message
-	response := request(t, s, "PUT", "/mytopic", "This is a message for firebase", nil)
-	msg := toMessage(t, response.Body.String())
-	require.NotEmpty(t, msg.ID)
-
-	// Keepalive message
-	require.Nil(t, s.firebase(newKeepaliveMessage(firebaseControlTopic)))
-
-	time.Sleep(500 * time.Millisecond) // Time for sends
-}
-
 func TestServer_PublishInvalidTopic(t *testing.T) {
 	s := newTestServer(t, newTestConfig(t))
 	s.mailer = &testMailer{}
@ -1018,7 +1019,7 @@ func TestServer_PublishAttachment(t *testing.T) {
 	require.Equal(t, int64(5000), msg.Attachment.Size)
 	require.GreaterOrEqual(t, msg.Attachment.Expires, time.Now().Add(179*time.Minute).Unix()) // Almost 3 hours
 	require.Contains(t, msg.Attachment.URL, "http://127.0.0.1:12345/file/")
-	require.Equal(t, "", msg.Attachment.Owner) // Should never be returned
+	require.Equal(t, "", msg.Sender) // Should never be returned
 	require.FileExists(t, filepath.Join(s.config.AttachmentCacheDir, msg.ID))

 	path := strings.TrimPrefix(msg.Attachment.URL, "http://127.0.0.1:12345")
@ -1047,7 +1048,7 @@ func TestServer_PublishAttachmentShortWithFilename(t *testing.T) {
 	require.Equal(t, int64(21), msg.Attachment.Size)
 	require.GreaterOrEqual(t, msg.Attachment.Expires, time.Now().Add(3*time.Hour).Unix())
 	require.Contains(t, msg.Attachment.URL, "http://127.0.0.1:12345/file/")
-	require.Equal(t, "", msg.Attachment.Owner) // Should never be returned
+	require.Equal(t, "", msg.Sender) // Should never be returned
 	require.FileExists(t, filepath.Join(s.config.AttachmentCacheDir, msg.ID))

 	path := strings.TrimPrefix(msg.Attachment.URL, "http://127.0.0.1:12345")
@ -1074,7 +1075,7 @@ func TestServer_PublishAttachmentExternalWithoutFilename(t *testing.T) {
 	require.Equal(t, "", msg.Attachment.Type)
 	require.Equal(t, int64(0), msg.Attachment.Size)
 	require.Equal(t, int64(0), msg.Attachment.Expires)
-	require.Equal(t, "", msg.Attachment.Owner)
+	require.Equal(t, "", msg.Sender)

 	// Slightly unrelated cross-test: make sure we don't add an owner for external attachments
 	size, err := s.messageCache.AttachmentBytesUsed("127.0.0.1")
@ -1095,7 +1096,7 @@ func TestServer_PublishAttachmentExternalWithFilename(t *testing.T) {
 	require.Equal(t, "", msg.Attachment.Type)
 	require.Equal(t, int64(0), msg.Attachment.Size)
 	require.Equal(t, int64(0), msg.Attachment.Expires)
-	require.Equal(t, "", msg.Attachment.Owner)
+	require.Equal(t, "", msg.Sender)
 }

 func TestServer_PublishAttachmentBadURL(t *testing.T) {
@ -1333,18 +1334,6 @@ func toHTTPError(t *testing.T, s string) *errHTTP {
 	return &e
 }

-func firebaseServiceAccountFile(t *testing.T) string {
-	if os.Getenv("NTFY_TEST_FIREBASE_SERVICE_ACCOUNT_FILE") != "" {
-		return os.Getenv("NTFY_TEST_FIREBASE_SERVICE_ACCOUNT_FILE")
-	} else if os.Getenv("NTFY_TEST_FIREBASE_SERVICE_ACCOUNT") != "" {
-		filename := filepath.Join(t.TempDir(), "firebase.json")
-		require.NotNil(t, os.WriteFile(filename, []byte(os.Getenv("NTFY_TEST_FIREBASE_SERVICE_ACCOUNT")), 0o600))
-		return filename
-	}
-	t.SkipNow()
-	return ""
-}
-
 func basicAuth(s string) string {
 	return fmt.Sprintf("Basic %s", base64.StdEncoding.EncodeToString([]byte(s)))
 }
--- a/server/smtp_server.go
+++ b/server/smtp_server.go
@ -3,10 +3,13 @@ package server
 import (
 	"bytes"
 	"errors"
+	"fmt"
 	"github.com/emersion/go-smtp"
 	"io"
 	"mime"
 	"mime/multipart"
+	"net/http"
+	"net/http/httptest"
 	"net/mail"
 	"strings"
 	"sync"
@ -23,25 +26,25 @@ var (
 // smtpBackend implements SMTP server methods.
 type smtpBackend struct {
 	config  *Config
-	sub     subscriber
+	handler func(http.ResponseWriter, *http.Request)
 	success int64
 	failure int64
 	mu      sync.Mutex
 }

-func newMailBackend(conf *Config, sub subscriber) *smtpBackend {
+func newMailBackend(conf *Config, handler func(http.ResponseWriter, *http.Request)) *smtpBackend {
 	return &smtpBackend{
-		config: conf,
-		sub:    sub,
+		config:  conf,
+		handler: handler,
 	}
 }

 func (b *smtpBackend) Login(state *smtp.ConnectionState, username, password string) (smtp.Session, error) {
-	return &smtpSession{backend: b}, nil
+	return &smtpSession{backend: b, remoteAddr: state.RemoteAddr.String()}, nil
 }

 func (b *smtpBackend) AnonymousLogin(state *smtp.ConnectionState) (smtp.Session, error) {
-	return &smtpSession{backend: b}, nil
+	return &smtpSession{backend: b, remoteAddr: state.RemoteAddr.String()}, nil
 }

 func (b *smtpBackend) Counts() (success int64, failure int64) {
@ -52,9 +55,10 @@ func (b *smtpBackend) Counts() (success int64, failure int64) {

 // smtpSession is returned after EHLO.
 type smtpSession struct {
-	backend *smtpBackend
-	topic   string
-	mu      sync.Mutex
+	backend    *smtpBackend
+	remoteAddr string
+	topic      string
+	mu         sync.Mutex
 }

 func (s *smtpSession) AuthPlain(username, password string) error {
@ -128,7 +132,7 @@ func (s *smtpSession) Data(r io.Reader) error {
 			m.Message = m.Title // Flip them, this makes more sense
 			m.Title = ""
 		}
-		if err := s.backend.sub(m); err != nil {
+		if err := s.publishMessage(m); err != nil {
 			return err
 		}
 		s.backend.mu.Lock()
@ -138,6 +142,25 @@ func (s *smtpSession) Data(r io.Reader) error {
 	})
 }

+func (s *smtpSession) publishMessage(m *message) error {
+	url := fmt.Sprintf("%s/%s", s.backend.config.BaseURL, m.Topic)
+	req, err := http.NewRequest("PUT", url, strings.NewReader(m.Message))
+	req.RemoteAddr = s.remoteAddr // rate limiting!!
+	req.Header.Set("X-Forwarded-For", s.remoteAddr)
+	if err != nil {
+		return err
+	}
+	if m.Title != "" {
+		req.Header.Set("Title", m.Title)
+	}
+	rr := httptest.NewRecorder()
+	s.backend.handler(rr, req)
+	if rr.Code != http.StatusOK {
+		return errors.New("error: " + rr.Body.String())
+	}
+	return nil
+}
+
 func (s *smtpSession) Reset() {
 	s.mu.Lock()
 	s.topic = ""
--- a/server/smtp_server_test.go
+++ b/server/smtp_server_test.go
@ -3,6 +3,9 @@ package server
 import (
 	"github.com/emersion/go-smtp"
 	"github.com/stretchr/testify/require"
+	"io"
+	"net"
+	"net/http"
 	"strings"
 	"testing"
 )
@ -27,13 +30,12 @@ Content-Type: text/html; charset="UTF-8"
 <div dir="ltr">what&#39;s up<br clear="all"><div><br></div></div>

 --000000000000f3320b05d42915c9--`
-	_, backend := newTestBackend(t, func(m *message) error {
-		require.Equal(t, "mytopic", m.Topic)
-		require.Equal(t, "and one more", m.Title)
-		require.Equal(t, "what's up", m.Message)
-		return nil
+	_, backend := newTestBackend(t, func(w http.ResponseWriter, r *http.Request) {
+		require.Equal(t, "/mytopic", r.URL.Path)
+		require.Equal(t, "and one more", r.Header.Get("Title"))
+		require.Equal(t, "what's up", readAll(t, r.Body))
 	})
-	session, _ := backend.AnonymousLogin(nil)
+	session, _ := backend.AnonymousLogin(fakeConnState(t, "1.2.3.4"))
 	require.Nil(t, session.Mail("phil@example.com", smtp.MailOptions{}))
 	require.Nil(t, session.Rcpt("ntfy-mytopic@ntfy.sh"))
 	require.Nil(t, session.Data(strings.NewReader(email)))
@ -59,13 +61,12 @@ Content-Type: text/html; charset="UTF-8"
 <div dir="ltr"><br></div>

 --000000000000bcf4a405d429f8d4--`
-	_, backend := newTestBackend(t, func(m *message) error {
-		require.Equal(t, "emailtest", m.Topic)
-		require.Equal(t, "", m.Title) // We flipped message and body
-		require.Equal(t, "This email has a subject but no body", m.Message)
-		return nil
+	_, backend := newTestBackend(t, func(w http.ResponseWriter, r *http.Request) {
+		require.Equal(t, "/emailtest", r.URL.Path)
+		require.Equal(t, "", r.Header.Get("Title")) // We flipped message and body
+		require.Equal(t, "This email has a subject but no body", readAll(t, r.Body))
 	})
-	session, _ := backend.AnonymousLogin(nil)
+	session, _ := backend.AnonymousLogin(fakeConnState(t, "1.2.3.4"))
 	require.Nil(t, session.Mail("phil@example.com", smtp.MailOptions{}))
 	require.Nil(t, session.Rcpt("ntfy-emailtest@ntfy.sh"))
 	require.Nil(t, session.Data(strings.NewReader(email)))
@ -81,14 +82,13 @@ Content-Type: text/plain; charset="UTF-8"

 what's up
 `
-	conf, backend := newTestBackend(t, func(m *message) error {
-		require.Equal(t, "mytopic", m.Topic)
-		require.Equal(t, "and one more", m.Title)
-		require.Equal(t, "what's up", m.Message)
-		return nil
+	conf, backend := newTestBackend(t, func(w http.ResponseWriter, r *http.Request) {
+		require.Equal(t, "/mytopic", r.URL.Path)
+		require.Equal(t, "and one more", r.Header.Get("Title"))
+		require.Equal(t, "what's up", readAll(t, r.Body))
 	})
 	conf.SMTPServerAddrPrefix = ""
-	session, _ := backend.AnonymousLogin(nil)
+	session, _ := backend.AnonymousLogin(fakeConnState(t, "1.2.3.4"))
 	require.Nil(t, session.Mail("phil@example.com", smtp.MailOptions{}))
 	require.Nil(t, session.Rcpt("mytopic@ntfy.sh"))
 	require.Nil(t, session.Data(strings.NewReader(email)))
@ -99,14 +99,13 @@ func TestSmtpBackend_Plaintext_No_ContentType(t *testing.T) {

 what's up
 `
-	conf, backend := newTestBackend(t, func(m *message) error {
-		require.Equal(t, "mytopic", m.Topic)
-		require.Equal(t, "Very short mail", m.Title)
-		require.Equal(t, "what's up", m.Message)
-		return nil
+	conf, backend := newTestBackend(t, func(w http.ResponseWriter, r *http.Request) {
+		require.Equal(t, "/mytopic", r.URL.Path)
+		require.Equal(t, "Very short mail", r.Header.Get("Title"))
+		require.Equal(t, "what's up", readAll(t, r.Body))
 	})
 	conf.SMTPServerAddrPrefix = ""
-	session, _ := backend.AnonymousLogin(nil)
+	session, _ := backend.AnonymousLogin(fakeConnState(t, "1.2.3.4"))
 	require.Nil(t, session.Mail("phil@example.com", smtp.MailOptions{}))
 	require.Nil(t, session.Rcpt("mytopic@ntfy.sh"))
 	require.Nil(t, session.Data(strings.NewReader(email)))
@ -121,11 +120,10 @@ Content-Type: text/plain; charset="UTF-8"

 what's up
 `
-	_, backend := newTestBackend(t, func(m *message) error {
-		require.Equal(t, "Three santas 🎅🎅🎅", m.Title)
-		return nil
+	_, backend := newTestBackend(t, func(w http.ResponseWriter, r *http.Request) {
+		require.Equal(t, "Three santas 🎅🎅🎅", r.Header.Get("Title"))
 	})
-	session, _ := backend.AnonymousLogin(nil)
+	session, _ := backend.AnonymousLogin(fakeConnState(t, "1.2.3.4"))
 	require.Nil(t, session.Mail("phil@example.com", smtp.MailOptions{}))
 	require.Nil(t, session.Rcpt("ntfy-mytopic@ntfy.sh"))
 	require.Nil(t, session.Data(strings.NewReader(email)))
@ -140,7 +138,7 @@ To: mytopic@ntfy.sh
 Content-Type: text/plain; charset="UTF-8"

 you know this is a string.
-it's a long string. 
+it's a long string.
 it's supposed to be longer than the max message length
 which is 4096 bytes,
 it used to be 512 bytes, but I increased that for the UnifiedPush support
@ -204,9 +202,9 @@ BBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBB
 BBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBB
 that should do it
 `
-	conf, backend := newTestBackend(t, func(m *message) error {
+	conf, backend := newTestBackend(t, func(w http.ResponseWriter, r *http.Request) {
 		expected := `you know this is a string.
-it's a long string. 
+it's a long string.
 it's supposed to be longer than the max message length
 which is 4096 bytes,
 it used to be 512 bytes, but I increased that for the UnifiedPush support
@ -266,13 +264,12 @@ AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA
 ......................................................................
 ......................................................................
 and with BBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBB
-BBBBBBBBBBBBBBBBBBBBBBBB`
+BBBBBBBBBBBBBBBBBBBBBBBBB`
 		require.Equal(t, 4096, len(expected)) // Sanity check
-		require.Equal(t, expected, m.Message)
-		return nil
+		require.Equal(t, expected, readAll(t, r.Body))
 	})
 	conf.SMTPServerAddrPrefix = ""
-	session, _ := backend.AnonymousLogin(nil)
+	session, _ := backend.AnonymousLogin(fakeConnState(t, "1.2.3.4"))
 	require.Nil(t, session.Mail("phil@example.com", smtp.MailOptions{}))
 	require.Nil(t, session.Rcpt("mytopic@ntfy.sh"))
 	require.Nil(t, session.Data(strings.NewReader(email)))
@ -288,21 +285,41 @@ Content-Type: text/SOMETHINGELSE

 what's up
 `
-	conf, backend := newTestBackend(t, func(m *message) error {
-		return nil
+	conf, backend := newTestBackend(t, func(http.ResponseWriter, *http.Request) {
+		// Nothing.
 	})
 	conf.SMTPServerAddrPrefix = ""
-	session, _ := backend.Login(nil, "user", "pass")
+	session, _ := backend.Login(fakeConnState(t, "1.2.3.4"), "user", "pass")
 	require.Nil(t, session.Mail("phil@example.com", smtp.MailOptions{}))
 	require.Nil(t, session.Rcpt("mytopic@ntfy.sh"))
 	require.Equal(t, errUnsupportedContentType, session.Data(strings.NewReader(email)))
 }

-func newTestBackend(t *testing.T, sub subscriber) (*Config, *smtpBackend) {
+func newTestBackend(t *testing.T, handler func(http.ResponseWriter, *http.Request)) (*Config, *smtpBackend) {
 	conf := newTestConfig(t)
 	conf.SMTPServerListen = ":25"
 	conf.SMTPServerDomain = "ntfy.sh"
 	conf.SMTPServerAddrPrefix = "ntfy-"
-	backend := newMailBackend(conf, sub)
+	backend := newMailBackend(conf, handler)
 	return conf, backend
 }
+
+func readAll(t *testing.T, rc io.ReadCloser) string {
+	b, err := io.ReadAll(rc)
+	if err != nil {
+		t.Fatal(err)
+	}
+	return string(b)
+}
+
+func fakeConnState(t *testing.T, remoteAddr string) *smtp.ConnectionState {
+	ip, err := net.ResolveIPAddr("ip", remoteAddr)
+	if err != nil {
+		t.Fatal(err)
+	}
+	return &smtp.ConnectionState{
+		Hostname:   "myhostname",
+		LocalAddr:  ip,
+		RemoteAddr: ip,
+	}
+}
--- a/server/topic.go
+++ b/server/topic.go
@ -15,7 +15,7 @@ type topic struct {
 }

 // subscriber is a function that is called for every new message on a topic
-type subscriber func(msg *message) error
+type subscriber func(v *visitor, msg *message) error

 // newTopic creates a new topic
 func newTopic(id string) *topic {
@ -42,12 +42,12 @@ func (t *topic) Unsubscribe(id int) {
 }

 // Publish asynchronously publishes to all subscribers
-func (t *topic) Publish(m *message) error {
+func (t *topic) Publish(v *visitor, m *message) error {
 	go func() {
 		t.mu.Lock()
 		defer t.mu.Unlock()
 		for _, s := range t.subscribers {
-			if err := s(m); err != nil {
+			if err := s(v, m); err != nil {
 				log.Printf("error publishing message to subscriber")
 			}
 		}
--- a/server/types.go
+++ b/server/types.go
@ -32,6 +32,7 @@ type message struct {
 	Actions    []*action   `json:"actions,omitempty"`
 	Attachment *attachment `json:"attachment,omitempty"`
 	PollID     string      `json:"poll_id,omitempty"`
+	Sender     string      `json:"-"`                  // IP address of uploader, used for rate limiting
 	Encoding   string      `json:"encoding,omitempty"` // empty for raw UTF-8, or "base64" for encoded bytes
 }

@ -41,7 +42,6 @@ type attachment struct {
 	Size    int64  `json:"size,omitempty"`
 	Expires int64  `json:"expires,omitempty"`
 	URL     string `json:"url"`
-	Owner   string `json:"-"` // IP address of uploader, used for rate limiting
 }

 type action struct {
--- a/server/visitor.go
+++ b/server/visitor.go
@ -28,6 +28,7 @@ type visitor struct {
 	emails        *rate.Limiter
 	subscriptions util.Limiter
 	bandwidth     util.Limiter
+	firebase      time.Time // Next allowed Firebase message
 	seen          time.Time
 	mu            sync.Mutex
 }
@ -48,14 +49,11 @@ func newVisitor(conf *Config, messageCache *messageCache, ip string) *visitor {
 		emails:        rate.NewLimiter(rate.Every(conf.VisitorEmailLimitReplenish), conf.VisitorEmailLimitBurst),
 		subscriptions: util.NewFixedLimiter(int64(conf.VisitorSubscriptionLimit)),
 		bandwidth:     util.NewBytesLimiter(conf.VisitorAttachmentDailyBandwidthLimit, 24*time.Hour),
+		firebase:      time.Unix(0, 0),
 		seen:          time.Now(),
 	}
 }

-func (v *visitor) IP() string {
-	return v.ip
-}
-
 func (v *visitor) RequestAllowed() error {
 	if !v.requests.Allow() {
 		return errVisitorLimitReached
@ -63,6 +61,21 @@ func (v *visitor) RequestAllowed() error {
 	return nil
 }

+func (v *visitor) FirebaseAllowed() error {
+	v.mu.Lock()
+	defer v.mu.Unlock()
+	if time.Now().Before(v.firebase) {
+		return errVisitorLimitReached
+	}
+	return nil
+}
+
+func (v *visitor) FirebaseTemporarilyDeny() {
+	v.mu.Lock()
+	defer v.mu.Unlock()
+	v.firebase = time.Now().Add(v.config.FirebaseQuotaExceededPenaltyDuration)
+}
+
 func (v *visitor) EmailAllowed() error {
 	if !v.emails.Allow() {
 		return errVisitorLimitReached
--- a/web/package-lock.json
+++ b/web/package-lock.json