Julien Herr 5fc91a0be4 refactor(html-processor): isolate cid rewrite from sanitization
Keep sanitizeElement single-purpose and run the cid: rewrite as a
separate guarded pass over [src] elements. Use a type-only import for
AttachmentData.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
2026-05-23 18:47:20 +02:00
2026-05-21 12:09:26 +02:00
2025-02-27 10:57:55 -08:00
2025-02-27 10:57:55 -08:00

kill-the-news

Convert email newsletters into private RSS feeds using Cloudflare Workers.

Self-hosted, uses your own domain, and keeps your data in your own Cloudflare account. Live at kill-the.news.

Why this exists

Many newsletters only support email delivery. RSS readers offer a better reading experience, but getting email-only newsletters into RSS usually means relying on shared third-party infrastructure.

kill-the-news keeps the same workflow while avoiding shared domains and shared data stores.

Features

  • One-click feed creation from an admin dashboard
  • Bulk feed/email deletion from the admin dashboard (safe checkbox-based flow)
  • Inline double-confirm delete interactions with toast feedback in the admin dashboard
  • Resizable + sortable table columns in the admin dashboard (Table view)
  • Unique newsletter addresses per feed (for example apple.mountain.42@yourdomain.com)
  • Cloudflare Email Workers ingestion (no third-party service)
  • ForwardEmail webhook ingestion with source-IP verification (optional alternative)
  • Optional per-feed sender allowlist (email@domain.com or domain.com)
  • RSS generation on demand (/rss/:feedId)
  • Atom feed at /atom/:feedId
  • Per-feed favicon derived from the last sender's domain (/favicon/:feedId), cached and shown in feeds + admin
  • Automatic RFC 8058 one-click unsubscribe when a feed is deleted — stops newsletters from mailing the now-dead address
  • Email attachments stored in Cloudflare R2 and exposed as RSS enclosures (optional)
  • Cloudflare KV storage for feed config + email metadata/content
  • Password-protected admin UI

Architecture

Two ingestion methods are supported — pick one or use both:

Method How it works
Cloudflare Email Workers Cloudflare Email Routing delivers the raw message directly to the Worker via the email() handler — no outbound webhook needed
ForwardEmail webhook ForwardEmail parses the message and POSTs a JSON payload to POST /api/inbound; the Worker verifies the source IP before processing

Common path:

  1. Incoming email arrives at user@yourdomain.com.
  2. The Worker resolves the feed from the recipient address and stores the email in KV.
  3. https://yourdomain.com/rss/:feedId renders RSS from stored items.
  4. /admin provides feed management and email deletion.
  5. https://yourdomain.com/ shows a public status page with monitoring counters and a link to the admin.

Main routes:

  • src/lib/cloudflare-email.ts: Cloudflare Email Workers ingestion
  • src/routes/inbound.ts: ForwardEmail webhook ingestion
  • src/routes/rss.ts: RSS rendering
  • src/routes/atom.ts: Atom feed rendering
  • src/routes/files.ts: attachment file serving from R2
  • src/routes/admin.ts: admin UI + feed CRUD
  • src/routes/home.tsx: public status page (GET /)
  • src/routes/stats.ts: monitoring counters API (GET /api/stats)

Monitoring

GET /api/stats returns JSON counters (public, no auth) for uptime/monitoring tools:

Field Meaning
active_feeds Feeds currently configured (live)
feeds_created Total feeds ever created (cumulative)
feeds_deleted Total feeds ever deleted (cumulative)
emails_received Total emails ingested successfully (cumulative)
emails_rejected Total emails rejected during validation (cumulative)
websub_subscriptions_active Active WebSub subscriptions (live)
last_email_at ISO 8601 date-time of the last ingested email
last_feed_created_at ISO 8601 date-time of the last feed creation
first_seen ISO 8601 date-time the instance first recorded a counter

The same figures are rendered on the public status page at GET /. Cumulative counters are persisted in the EMAIL_STORAGE KV under the stats:counters key.

Requirements

  • Node.js 20+
  • A Cloudflare account (free plan works — Workers, KV, and Email Routing are all included)
  • A domain added to Cloudflare as a zone (DNS managed by Cloudflare)
  • A ForwardEmail account (Option B only)

Cloudflare setup

If your domain is not yet on Cloudflare: in the Cloudflare dashboard, go to Add a site, enter your domain, choose the Free plan, and follow the instructions to update your nameservers at your registrar. Wait for the zone to become active (usually a few minutes).

Setup

  1. Clone this repository.

  2. Authenticate Wrangler:

    npx wrangler login
    
  3. Run setup:

    bash setup.sh
    

    The script will prompt for an admin password and your domain, then:

    • install npm dependencies
    • verify Cloudflare auth (wrangler whoami)
    • create KV namespaces (EMAIL_STORAGE + preview) in your account
    • set the ADMIN_PASSWORD secret in the production environment
    • generate wrangler.toml from wrangler-example.toml with your KV IDs, domain, and today's compatibility date
  4. Configure email ingestion — choose one of the two options below.

No third-party service required. Cloudflare receives the email and hands it directly to the Worker.

  1. In the Cloudflare dashboard, go to Email → Email Routing for your zone and click Enable Email Routing. Cloudflare will prompt you to add MX and SPF records — accept and it adds them automatically.
  2. Under Email Routing → Routing Rules, add a Catch-all rule:
    • Action: Send to Worker
    • Worker: kill-the-news (the name from wrangler.toml)

That's it. No webhook configuration is needed.

Option B — ForwardEmail (alternative)

Use this if you prefer ForwardEmail's additional features (sender filtering, open-tracking, etc.).

Add these DNS records in Cloudflare (DNS → Records):

Type Name Content Notes
MX @ mx1.forwardemail.net Priority 10, DNS only
MX @ mx2.forwardemail.net Priority 10, DNS only
TXT @ "forward-email=https://yourdomain.com/api/inbound" webhook target
TXT @ "v=spf1 include:spf.forwardemail.net -all" SPF

Replace yourdomain.com with your actual domain.

The Worker verifies each webhook request against ForwardEmail's published MX IP list before processing it.

  1. Deploy:

    npm run deploy
    

    Wrangler will create the Worker and register yourdomain.com (and www.yourdomain.com) as custom domains pointing to it. Cloudflare handles TLS automatically.

  2. Open https://yourdomain.com/admin and sign in.

Tip: To verify the Worker is running, check Workers & Pages → kill-the-news in the Cloudflare dashboard. The Custom Domains tab should list your domain once the deploy succeeds.

Development

npm install
npm run dev
npm test
npm run build

Continuous deployment (GitHub Actions)

The repo ships a Deploy Demo workflow that generates wrangler.toml from wrangler-example.toml and runs wrangler deploy --env demo after CI passes on main. To wire up your own automated deploys, set these repository secrets (Settings → Secrets and variables → Actions):

Secret Purpose
CLOUDFLARE_API_TOKEN Scoped API token used by Wrangler to deploy (see permissions below)
CLOUDFLARE_ACCOUNT_ID Target Cloudflare account ID
DEMO_KV_NAMESPACE_ID KV namespace ID substituted into the generated wrangler.toml
DEMO_ADMIN_PASSWORD Admin password set via wrangler secret put

Deploy token permissions

Local npx wrangler login uses OAuth and already has every permission, so the gaps below only bite scoped API tokens (i.e. CI). Create the token at https://dash.cloudflare.com/profile/api-tokens — the "Edit Cloudflare Workers" template is the easiest base — and make sure it carries the permissions matching the bindings you actually deploy:

Permission Needed for
Account · Workers Scripts · Edit Deploying the Worker and running wrangler secret put
Account · Workers KV Storage · Edit The EMAIL_STORAGE KV binding
Account · Workers R2 Storage · Edit The ATTACHMENT_BUCKET R2 binding (only when attachments are enabled)
Zone · Workers Routes · Edit + DNS · Edit The custom_domain routes (e.g. demo.kill-the.news), scoped to its zone

Scope the token to the relevant account and, for custom domains, the relevant zone. A missing R2 permission fails with Authentication error [code: 10000] on /r2/buckets/...; a missing routes/DNS permission fails while provisioning the custom domain. The User Details/Memberships warnings Wrangler prints are only for whoami display and are not fatal.

Configuration notes

  • wrangler-example.toml is the template; wrangler.toml is generated locally.
  • Keep compatibility_date fresh when doing runtime upgrades.
  • ADMIN_PASSWORD is a Cloudflare Worker secret, not a plain env var in config.

Feed size limit

By default the worker keeps emails until the feed's stored data exceeds 512 KB, then drops the oldest entries (and their KV records) to stay under the limit. This is more robust than a fixed entry count for HTML-heavy newsletters.

To override the threshold, add to wrangler.toml under [vars]:

FEED_MAX_SIZE_BYTES = "524288"   # 512 KB — adjust as needed

Email attachments (R2)

When an incoming email contains attachments, the Worker can store them in a Cloudflare R2 bucket and expose them as <enclosure> elements in the RSS feed (and <link rel="enclosure"> in Atom). Each attachment is served at /files/{id}/{filename} with an immutable cache header. Attachments are also listed with download links on the admin email detail page and the public entry view.

This feature is optional. If no R2 bucket is bound, attachments are silently ignored and nothing else changes.

Setup (automated): setup.sh now asks "Enable email attachments stored in R2?". Answer yes and it creates the buckets (<worker>-attachments and <worker>-attachments-preview) and wires the binding into the generated wrangler.toml for you.

Setup (manual):

  1. Create an R2 bucket in the Cloudflare dashboard (R2 Object Storage → Create bucket), or with Wrangler:
    npx wrangler r2 bucket create your-bucket-name
    
  2. In wrangler.toml, uncomment and fill in the R2 binding (the commented block from wrangler-example.toml):
    r2_buckets = [
      { binding = "ATTACHMENT_BUCKET", bucket_name = "your-bucket-name", preview_bucket_name = "your-bucket-name-preview" }
    ]
    
    The binding is per environment: add it under every env you deploy ([env.production], [env.demo], …), each pointing at its own bucket.
  3. Redeploy:
    npm run deploy
    

Deploy token permission: with an R2 binding, wrangler deploy verifies the bucket exists, so a scoped CI token also needs Account → Workers R2 Storage — see Continuous deployment. Local npx wrangler login already has it.

Turning it off: set ATTACHMENTS_ENABLED = "false" in [vars] to disable attachments even while the R2 bucket stays bound (useful to cap usage on a demo). Any other value (or leaving it unset) keeps the feature on whenever R2 is configured.

Attachments are deleted from R2 automatically when the corresponding email is deleted from the admin UI, or when an email is dropped during feed size trimming.

Monitoring storage / free tier: the status page (/) and /api/stats report R2 space used (against the 10 GB R2 free tier) and an estimate of KV space used (against the 1 GB KV free tier). The figures are refreshed hourly by the cron trigger. KV usage is an estimate based on stored email sizes, so treat it as a lower bound.

External auth provider (Authelia / Authentik / reverse proxy)

Instead of the built-in password login you can delegate admin authentication to a reverse proxy that sets a trusted user header (Remote-User or X-Forwarded-User).

Required Worker secrets (set with wrangler secret put, never in [vars]):

Secret Description
PROXY_AUTH_SECRET Shared secret between the proxy and the Worker

Required [vars] in wrangler.toml:

PROXY_TRUSTED_IPS = "10.0.0.1"   # comma-separated IPs of your reverse proxy

When both are configured, the Worker authenticates a request if:

  1. CF-Connecting-IP is in PROXY_TRUSTED_IPS
  2. The X-Auth-Proxy-Secret header matches PROXY_AUTH_SECRET
  3. Remote-User or X-Forwarded-User is non-empty

Password login remains available as a fallback when the proxy check fails.

Security note: CF-Connecting-IP can be spoofed on direct workers.dev requests. Disable the workers.dev subdomain in production (workers_dev = false in [env.production]).

Security notes

  • When using Option B (ForwardEmail), inbound webhook access is IP-restricted to ForwardEmail MX sources.
  • Admin auth uses a signed, HttpOnly, Secure, SameSite=Strict cookie.
  • Admin responses are no-store to avoid cache leakage.
  • For high-value feeds, set Allowed senders so only known sender addresses/domains are accepted.
  • You should use a strong admin password and rotate periodically.
  • All secret comparisons (admin password, proxy secret) use constant-time comparison to prevent timing attacks.

Upgrading dependencies

To refresh dependencies to latest:

npm outdated
npm install
npm test
npm run build

Then update compatibility_date and redeploy.

Acknowledgements

  • kill-the-newsletter by Leandro Facchinetti — the inspiration for this project and the reference implementation for feature ideas (Atom feeds, attachment enclosures, entry HTML views, and more).
  • Email-to-RSS by yl8976 — the initial codebase this project is based on.

License

MIT

S
Description
No description provided
Readme MIT 1.3 MiB
Languages
TypeScript 91.8%
CSS 6.1%
Shell 1.8%
JavaScript 0.3%