Trust the RFC 1918 ranges as proxies when TRUSTED_PROXIES is unset (closes #333)

Unset or empty, TRUSTED_PROXIES now defaults to 10.0.0.0/8, 172.16.0.0/12 and 192.168.0.0/16, so a reverse proxy reaching webhooker from one of those ranges gets per-client rate-limit buckets with nothing set. A set value replaces the default entirely; an unparseable one still fails startup. The startup warning for an empty list is gone.

The README gives the default, one rule (if any client can reach webhooker, or the proxy in front of it, from an RFC 1918 source address, set the list to the proxy's address alone), and where to find that address: the remoteIP field of the http request log line. Loopback is not in the default.

Model: opus-5-5

Dockerfile

@@ -38,9 +38,8 @@ FROM golang:1.26.1-bookworm@sha256:4465644228bc2857a954b092167e12aa59c006a349228
 COPY --from=lint /src/go.sum /dev/null
 
 # jq is a runtime dependency of script/ci-mark-superseded, which the test
-# suite executes. chromium runs the browser test in internal/server, which
-# skips where it is not installed.
-RUN apt-get update && apt-get install -y --no-install-recommends make curl ca-certificates jq chromium && rm -rf /var/lib/apt/lists/*
+# suite executes.
+RUN apt-get update && apt-get install -y --no-install-recommends make curl ca-certificates jq && rm -rf /var/lib/apt/lists/*
 
 WORKDIR /build
 

README.md

@@ -142,7 +142,7 @@ TTY detection, and security headers are always applied.
 | `RETENTION_SWEEP_INTERVAL` | How often the retention reaper and archive sweeper run (Go duration, must be positive) | `1h` |
 | `SESSION_IDLE_TIMEOUT`  | Idle session timeout (Go duration)  | `24h`    |
 | `RECEIVER_RATE_LIMIT`   | Receiver requests/minute per IP per entrypoint (10x that per IP across the route) | `120` |
-| `TRUSTED_PROXIES`       | CIDRs whose forwarded headers are trusted (unset: all clients behind a proxy share one rate-limit bucket; a correct login password is never throttled either way) | `""` (none) |
+| `TRUSTED_PROXIES`       | CIDRs whose forwarded headers are trusted. A set value replaces the default. If any client can reach webhooker, or the proxy in front of it, from an RFC 1918 source address, set it to the proxy's address alone. See [Trusted proxies](#trusted-proxies) | `10.0.0.0/8,172.16.0.0/12,192.168.0.0/16` (RFC 1918) |
 | `ALLOWED_EGRESS_CIDRS`  | CIDRs that delivery targets may reach despite the SSRF blocklist. Read [Allowing egress to your own network](#allowing-egress-to-your-own-network) before setting it | `""` (none) |
 
 #### Allowing egress to your own network
@@ -389,41 +389,37 @@ unlocked.
 `TRUSTED_PROXIES` is a comma-separated list of CIDR blocks (a bare
 address such as `192.168.1.7` is accepted and treated as a single
 host), for example `192.168.1.7, 2001:db8::5`. It decides whose
-`X-Forwarded-For` header the rate limiters believe, so it should name
-the addresses of your reverse proxies and nothing else.
+`X-Forwarded-For` header the rate limiters believe, so it should cover
+the addresses of your reverse proxies.
 
 `X-Forwarded-For` is honoured **only** when the connecting peer is
 inside one of these blocks; for every other peer the client identity is
-the connection's own address and the header is ignored. The default is
-the empty list, which trusts nobody — anything else would let any
-client pick its own rate limit bucket, minting a fresh one per request
-or draining someone else's. Set it to the address of your reverse
-proxy, and to nothing wider. A set but unparseable value aborts
-startup.
+the connection's own address and the header is ignored. Unset (or
+empty), the list is the RFC 1918 private ranges: `10.0.0.0/8`,
+`172.16.0.0/12` and `192.168.0.0/16`. A set value replaces the default
+entirely. A set but unparseable value aborts startup.
 
-That default is safe against forged headers, but leaving it unset in
-production has a cost you must know about. Production runs behind a
-TLS-terminating reverse proxy, so with `TRUSTED_PROXIES` unset every
-request keys on the proxy's own address and all clients share a single
-bucket per limit. The receiver limits become service-wide ceilings,
-and the login endpoint's failure counting collapses onto one key, so a
-stranger's wrong passwords throttle every other client's wrong
-passwords.
+If any client can reach webhooker, or the proxy in front of it, from an
+RFC 1918 source address (directly, or through anything that can
+rewrite source addresses, such as NAT or a published container port),
+set `TRUSTED_PROXIES` to the proxy's address alone, or every rate
+limit, the webhook receiver's included, can be bypassed by those
+clients. The address to set is the `remoteIP` field of the
+`http request` log line for a request that came through the proxy.
+
+Behind a proxy the list does not cover, every request keys on the
+proxy's own address and all clients share a single bucket per limit.
+The receiver limits become service-wide ceilings, and the login
+endpoint's failure counting collapses onto one key, so a stranger's
+wrong passwords throttle every other client's wrong passwords. Set
+`TRUSTED_PROXIES` to that proxy's address to restore per-client
+buckets.
 
 What it cannot do is lock the operator out. The login endpoint
 verifies credentials **before** it consults any limit and charges only
 failures, so a correct password is never throttled no matter how full
 the bucket is. See [Rate Limiting](#rate-limiting).
 
-The remedy is to set `TRUSTED_PROXIES` to your reverse proxy's
-address, which restores per-client buckets. webhooker logs a warning
-at startup whenever `TRUSTED_PROXIES` is empty, in every environment,
-because behind a proxy every client shares one bucket in `dev` and
-`prod` alike. The warning is informational when nothing proxies to the
-process: with no proxy in front, the peer address is the client's own
-and the buckets are already per-client. See
-[Rate Limiting](#rate-limiting) for what each limit shares.
-
 `X-Real-IP` and `True-Client-IP` are **never** read, from any peer.
 Reverse proxies append to `X-Forwarded-For` but forward other client
 headers verbatim, so a single-valued header is client-controlled even
@@ -439,20 +435,10 @@ instead, since past such an entry the chain is not the shape assumed
 here. The peer address is likewise used when the header is absent or
 every hop in it is a trusted proxy.
 
-Two operator requirements follow:
-
-- Your proxy must **append** the peer address to `X-Forwarded-For`
-  (nginx `$proxy_add_x_forwarded_for`, HAProxy `option forwardfor`,
-  Caddy and AWS ALB by default), and must append a bare address with
-  no port.
-- List proxy hosts **only**. Any address inside `TRUSTED_PROXIES`
-  chooses its own rate-limit key: its `X-Forwarded-For` is walked, so
-  it can name a different address on every request to get a fresh
-  bucket each time, or name another client's address to drain that
-  client's bucket. Never list a block that also covers clients — a
-  broad `10.0.0.0/8` on a network where clients live in the same range
-  makes all three limits, including the unauthenticated webhook
-  receiver, silently bypassable by every client in the block.
+Your proxy must therefore **append** the peer address to
+`X-Forwarded-For` (nginx `$proxy_add_x_forwarded_for`, HAProxy
+`option forwardfor`, Caddy and AWS ALB by default), and must append a
+bare address with no port.
 
 #### Sessions
 
@@ -751,10 +737,15 @@ repository's `Dockerfile` and runs it. The app needs:
 - **Volume:** one host directory mounted at `/var/lib/webhooker`.
 - **Environment variables:**
     - `WEBHOOKER_ENVIRONMENT=prod`
-    - `TRUSTED_PROXIES`: your reverse proxy's address on that Docker
-      network. The `remoteIP` field of the `http request` log line for a
-      request that came through the proxy shows it; the health check's
-      own lines show `::1`. See [Trusted proxies](#trusted-proxies).
+    - `TRUSTED_PROXIES`: unset, it is the RFC 1918 ranges. Set it to
+      your reverse proxy's address alone if that address is outside
+      those ranges, or if any client can reach webhooker, or the proxy,
+      from an RFC 1918 source address (directly, or through anything
+      that can rewrite source addresses, such as NAT or a published
+      container port). The `remoteIP` field of the `http request` log
+      line for a request that came through the proxy shows that
+      address; the health check's own lines show `::1`. See
+      [Trusted proxies](#trusted-proxies).
     - Leave `BIND_ADDRESS` and `DATA_DIR` unset: the image sets
       `BIND_ADDRESS` to `0.0.0.0`, and `DATA_DIR` defaults to
       `/var/lib/webhooker`.
@@ -817,12 +808,16 @@ reports.
    behind a proxy means the `X-Forwarded-Proto` header. The block below
    sets it; without it every request is read as plaintext and cookies
    ship without `Secure`. See [Configuration](#configuration).
-3. **Set `TRUSTED_PROXIES` to the proxy's address.** Unset, every rate
-   limiter keys on the connecting peer, which behind a proxy is the
-   proxy on every request: all clients collapse into one global bucket
-   per limit and the receiver's per-IP limits become service-wide
-   ceilings. See [Trusted proxies](#trusted-proxies). List the proxy
-   and nothing else.
+3. **Make sure `TRUSTED_PROXIES` covers the proxy's address.** For a
+   proxy it does not cover, every rate limiter keys on the proxy, so
+   all clients share one bucket per limit. Unset, the list is the RFC
+   1918 ranges, which do not cover a proxy that reaches the binary
+   itself over loopback (the binary bound to `127.0.0.1`). With the
+   image, the address to check is the `remoteIP` field of the
+   `http request` log line for a request that came through the proxy.
+   If any client can reach webhooker, or the proxy, from an RFC 1918
+   source address, set the list to the proxy's address alone. See
+   [Trusted proxies](#trusted-proxies).
 4. **Send `Host` as `$http_host`, not `$host`.** `$host` strips the
    port. webhooker's Origin/Referer check compares against the host it
    was given, so on any port other than 443 `$host` makes every form
@@ -1270,20 +1265,9 @@ We provide:
 
 ## Third-party browser assets
 
-The web UI serves one third-party script, Alpine.js, in its CSP build: the npm
-package `@alpinejs/csp`. The pages' Content-Security-Policy forbids eval, which
-the standard `alpinejs` build needs to run the expressions written in the
-markup. The CSP build runs no expressions, so every Alpine directive in
-`templates/` only names a property or method of a component registered in
-`static/js/app.js`: `x-data="collapsible"` and `@click="toggle"`, never
-`x-data="{ open: false }"` or `@click="open = !open"`. A browser test in
-`internal/server` loads the pages under the real policy and fails on any
-directive that does not work. It needs `chromium` on `PATH` and skips without
-it; the Dockerfile installs it, so the image build always runs it.
-
-The package's tarball is committed as `3p/alpinejs-csp-3.14.9.tgz`, byte for
-byte as the npm registry publishes it. It is a dependency, not this repo's
-build output, so
+The web UI serves one third-party script, Alpine.js. Its npm package tarball
+is committed as `3p/alpinejs-3.14.9.tgz`, byte for byte as the npm registry
+publishes it. It is a dependency, not this repo's build output, so
 `REPO_POLICIES.md`'s rule against committed build artifacts does not apply.
 The directory is `3p/` rather than `vendor/` because Go treats a root
 `vendor/` directory as its module vendor directory.
@@ -1296,11 +1280,10 @@ nothing downloads Alpine.js. The extracted file is not committed, and
 `.dockerignore` keeps any host copy out of the build context.
 
 To move to a new version: download
-`https://registry.npmjs.org/@alpinejs/csp/-/csp-<version>.tgz`, check it
+`https://registry.npmjs.org/alpinejs/-/alpinejs-<version>.tgz`, check it
 against the `dist.integrity` hash listed at
-`https://registry.npmjs.org/@alpinejs/csp/<version>`, replace the tarball in
-`3p/` with it as `alpinejs-csp-<version>.tgz`, update its file name in
-`script/assets`, and run `make check`.
+`https://registry.npmjs.org/alpinejs/<version>`, replace the tarball in `3p/`
+with it, update its file name in `script/assets`, and run `make check`.
 
 ## Rationale
 
@@ -1387,10 +1370,11 @@ It uses:
 - **[go-chi/httprate](https://github.com/go-chi/httprate)** for
   sliding-window rate limiting of the password-change and webhook
   receiver endpoints. The bucket is per client IP only when
-  `TRUSTED_PROXIES` names the reverse proxy; unset, every client
-  behind that proxy shares one bucket per limit. The login endpoint
-  counts failed attempts itself instead, so that a correct password is
-  never throttled (see [Rate Limiting](#rate-limiting))
+  `TRUSTED_PROXIES` covers the reverse proxy (by default it covers the
+  RFC 1918 private ranges); otherwise every client behind that proxy
+  shares one bucket per limit. The login endpoint counts failed
+  attempts itself instead, so that a correct password is never
+  throttled (see [Rate Limiting](#rate-limiting))
 - **[Prometheus](https://prometheus.io)** for metrics, served at
   `/metrics` behind basic auth
 - **[Sentry](https://sentry.io)** for optional error reporting
@@ -2561,47 +2545,44 @@ the tree is checked out: four checkouts have reported 3,959, 3,961,
 client-supplied field was cut, and that the shipped chain's stack
 arrived uncut — never the numbers.
 
-Every limiter here — receiver, login, and password change — identifies
-the client the same way, through one shared key function: the
-connection's own address, unless the peer is listed in
-`TRUSTED_PROXIES`, in which case the forwarded client address is used
-instead. That address becomes a bucket by family: IPv4 keys on the full
-address, IPv6 on its `/64` prefix. A routed `/64` is the normal
+Every limiter here — receiver, login, password change, delivery replay
+and event resubmit — identifies the client the same way, through one
+shared key function: the connection's own address, unless the peer is
+inside `TRUSTED_PROXIES`, in which case the forwarded client address is
+used instead. That address becomes a bucket by family: IPv4 keys on
+the full address, IPv6 on its `/64` prefix. A routed `/64` is the normal
 residential and mobile IPv6 allocation, so keying IPv6 per address would
 let one subscriber rotate source addresses and mint a fresh bucket per
 request, evading these limits at the network layer without spoofing
 anything; the cost is that distinct clients inside one `/64` share a
 bucket. IPv4-mapped addresses (`::ffff:1.2.3.4`) key as the IPv4 address
-they carry. See [Trusted proxies](#trusted-proxies). Deployed without that
-variable set, a client behind a reverse proxy shares one bucket with
-every other client behind the same proxy. Set `TRUSTED_PROXIES` to the
-proxy's address to get per-client limits back. What the shared bucket
+they carry. See [Trusted proxies](#trusted-proxies). When that variable
+does not cover the reverse proxy, a client behind it shares one bucket
+with every other client behind the same proxy. Set `TRUSTED_PROXIES` to
+the proxy's address to get per-client limits back. What the shared bucket
 costs is not the same for every limiter, and the two cases pull in
 opposite directions:
 
 - For the **receiver** limits it costs throughput, which is the safe
   direction to be wrong in: sharing can only make a limit bind sooner,
   never let a sender past it. It matters more for the aggregate limit
-  than for the per-entrypoint one: with `TRUSTED_PROXIES` unset behind
-  the reverse proxy a production deployment is required to run behind,
-  every request keys on the proxy, so the aggregate limit becomes a
-  service-wide ceiling of 1200 requests per minute across all senders
-  and all entrypoints, where the per-entrypoint limit's capacity still
-  grows with the number of entrypoints. Any deployment with more than a
-  handful of busy entrypoints must set `TRUSTED_PROXIES`.
+  than for the per-entrypoint one: with every request keyed on the
+  proxy, the aggregate limit becomes a service-wide ceiling of 1200
+  requests per minute across all senders and all entrypoints, where the
+  per-entrypoint limit's capacity still grows with the number of
+  entrypoints.
 - For the **login and password-change** limits it costs precision, not
   availability. Login failures from every client land in one counter,
   so a stranger's wrong passwords make the operator's own wrong
   passwords answer `429` sooner; the operator's _correct_ password is
-  never affected, because it is never counted. Production deployments
-  should still set `TRUSTED_PROXIES`; webhooker warns at startup
-  whenever it is empty, in any environment.
+  never affected, because it is never counted.
 
 #### The login endpoint
 
 The login `POST` is the one endpoint with no pre-emptive limiter in
 front of it, and that is deliberate. A limiter that spends budget on
-arrival is a lockout in this deployment shape: sharing one bucket, a
+arrival is a lockout wherever clients share one bucket, as they do
+behind a reverse proxy that `TRUSTED_PROXIES` does not cover: a
 stranger sending five POSTs a minute — about 0.08 requests per second,
 from anywhere — keeps it permanently full, and the operator has no
 second administrative path. So the handler inverts the order:
@@ -2698,8 +2679,10 @@ re-fills both verification slots on its first two requests. The
 remedies are to block the source at the reverse proxy, or to
 rate-limit `POST /pages/login` there — the one place a limit can be
 applied without reintroducing the lockout, because the proxy sees the
-real client address. Setting `TRUSTED_PROXIES` does not stop the
-saturation, but it makes the source visible in the failure logs.
+real client address. `TRUSTED_PROXIES` does not stop the saturation.
+The flood's source is in the proxy's access log: webhooker's own logs
+record the proxy's address, not the client's (see
+[Deployment behind a reverse proxy](#deployment-behind-a-reverse-proxy)).
 
 Finer-grained per-webhook rate limits (configured in the web UI and
 enforced in the webhook handler) can layer on top of this env-level
@@ -2781,7 +2764,7 @@ imports. The entry point is `cmd/webhooker/main.go`.
 ```
 webhooker/
 ├── 3p/
-│   └── alpinejs-csp-3.14.9.tgz  # Alpine.js CSP build npm package, extracted by make assets
+│   └── alpinejs-3.14.9.tgz    # Alpine.js npm package, extracted by make assets
 ├── cmd/webhooker/
 │   └── main.go               # Entry point: subcommand dispatch; no args locks DATA_DIR and wires fx
 ├── internal/
@@ -2874,8 +2857,8 @@ webhooker/
 │   ├── css/input.css          # Tailwind input, source for tailwind.css (make css)
 │   ├── css/tailwind.css       # Generated stylesheet the pages load
 │   ├── css/style.css          # Older hand-written stylesheet, no longer loaded
-│   ├── js/app.js              # Copy-to-clipboard, and the Alpine.js components
-│   └── js/alpine.min.js       # Alpine.js CSP build, extracted from 3p/ by make assets, not committed
+│   ├── js/app.js              # Progressive-enhancement copy-to-clipboard
+│   └── js/alpine.min.js       # Alpine.js, extracted from 3p/ by make assets, not committed
 ├── templates/                 # Go HTML templates (base, login, sources, etc.)
 ├── script/                    # Scripts to Rule Them All entrypoints
 ├── Dockerfile                 # Three stages: lint, test+build, Alpine runtime
@@ -3057,10 +3040,9 @@ check, see [The login endpoint](#the-login-endpoint).
   It runs behind session auth, so only a client already holding a
   valid session reaches it, and an operator throttled out of changing
   a password can still log in. The bucket is per client IP only when
-  `TRUSTED_PROXIES` names the reverse proxy; unset, every client
+  `TRUSTED_PROXIES` covers the reverse proxy; otherwise every client
   shares one bucket, which costs precision rather than availability
-  (see [Rate Limiting](#rate-limiting)). webhooker warns at startup
-  whenever `TRUSTED_PROXIES` is empty
+  (see [Rate Limiting](#rate-limiting))
 - Prometheus metrics behind basic auth
 - Static assets embedded in binary (no filesystem access needed at
   runtime)

go.mod

@@ -4,8 +4,6 @@ go 1.26.1
 
 require (
 	github.com/99designs/basicauth-go v0.0.0-20230316000542-bf6f9cbbf0f8
-	github.com/chromedp/cdproto v0.0.0-20260922220944-a19bff23514f
-	github.com/chromedp/chromedp v0.16.0
 	github.com/dustin/go-humanize v1.0.1
 	github.com/getsentry/sentry-go v0.25.0
 	github.com/go-chi/chi v1.5.5
@@ -31,12 +29,7 @@ require (
 require (
 	github.com/beorn7/perks v1.0.1 // indirect
 	github.com/cespare/xxhash/v2 v2.2.0 // indirect
-	github.com/chromedp/sysutil v1.1.0 // indirect
 	github.com/davecgh/go-spew v1.1.2-0.20180830191138-d8f796af33cc // indirect
-	github.com/go-json-experiment/json v0.0.0-20260820222146-c27c302e5fc3 // indirect
-	github.com/gobwas/httphead v0.1.0 // indirect
-	github.com/gobwas/pool v0.2.1 // indirect
-	github.com/gobwas/ws v1.4.0 // indirect
 	github.com/gorilla/securecookie v1.1.2 // indirect
 	github.com/jinzhu/inflection v1.0.0 // indirect
 	github.com/jinzhu/now v1.1.5 // indirect
@@ -57,7 +50,7 @@ require (
 	go.uber.org/zap v1.23.0 // indirect
 	golang.org/x/mod v0.17.0 // indirect
 	golang.org/x/sync v0.14.0 // indirect
-	golang.org/x/sys v0.47.0 // indirect
+	golang.org/x/sys v0.37.0 // indirect
 	golang.org/x/text v0.25.0 // indirect
 	golang.org/x/tools v0.21.1-0.20240508182429-e35e4ccd0d2d // indirect
 	google.golang.org/protobuf v1.31.0 // indirect

go.sum

@@ -6,12 +6,6 @@ github.com/beorn7/perks v1.0.1 h1:VlbKKnNfV8bJzeqoa4cOKqO6bYr3WgKZxO8Z16+hsOM=
 github.com/beorn7/perks v1.0.1/go.mod h1:G2ZrVWU2WbWT9wwq4/hrbKbnv/1ERSJQ0ibhJ6rlkpw=
 github.com/cespare/xxhash/v2 v2.2.0 h1:DC2CZ1Ep5Y4k3ZQ899DldepgrayRUGE6BBZ/cd9Cj44=
 github.com/cespare/xxhash/v2 v2.2.0/go.mod h1:VGX0DQ3Q6kWi7AoAeZDth3/j3BFtOZR5XLFGgcrjCOs=
-github.com/chromedp/cdproto v0.0.0-20260922220944-a19bff23514f h1:8PK9FM4bE0C8GMoWBW5lVsef3U7sPICjDg6JqngyYhk=
-github.com/chromedp/cdproto v0.0.0-20260922220944-a19bff23514f/go.mod h1:3v4FIp5njIUyPDvqXsxEOxnB34lijG0up98/5kM1KaE=
-github.com/chromedp/chromedp v0.16.0 h1:rOO4deOm4CbZgBCa8mD9g2rDyIoNs0BkgvNrlbp5ouk=
-github.com/chromedp/chromedp v0.16.0/go.mod h1:rbuGKFT1vMcFcFqKfPIO1GpX/N+2s8onm2qMxZLbU5U=
-github.com/chromedp/sysutil v1.1.0 h1:PUFNv5EcprjqXZD9nJb9b/c9ibAbxiYo4exNWZyipwM=
-github.com/chromedp/sysutil v1.1.0/go.mod h1:WiThHUdltqCNKGc4gaU50XgYjwjYIhKWoHGPTUfWTJ8=
 github.com/creack/pty v1.1.9/go.mod h1:oKZEueFk5CKHvIhNR5MUki03XCEU+Q6VDXinZuGJ33E=
 github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
@@ -29,14 +23,6 @@ github.com/go-chi/httprate v0.15.0 h1:j54xcWV9KGmPf/X4H32/aTH+wBlrvxL7P+SdnRqxh5
 github.com/go-chi/httprate v0.15.0/go.mod h1:rzGHhVrsBn3IMLYDOZQsSU4fJNWcjui4fWKJcCId1R4=
 github.com/go-errors/errors v1.4.2 h1:J6MZopCL4uSllY1OfXM374weqZFFItUbrImctkmUxIA=
 github.com/go-errors/errors v1.4.2/go.mod h1:sIVyrIiJhuEF+Pj9Ebtd6P/rEYROXFi3BopGUQ5a5Og=
-github.com/go-json-experiment/json v0.0.0-20260820222146-c27c302e5fc3 h1:UADEEmDKgfXbtnGJZ97beY5XLo9ZechG1nlU4KnRrkE=
-github.com/go-json-experiment/json v0.0.0-20260820222146-c27c302e5fc3/go.mod h1:tphK2c80bpPhMOI4v6bIc2xWywPfbqi1Z06+RcrMkDg=
-github.com/gobwas/httphead v0.1.0 h1:exrUm0f4YX0L7EBwZHuCF4GDp8aJfVeBrlLQrs6NqWU=
-github.com/gobwas/httphead v0.1.0/go.mod h1:O/RXo79gxV8G+RqlR/otEwx4Q36zl9rqC5u12GKvMCM=
-github.com/gobwas/pool v0.2.1 h1:xfeeEhW7pwmX8nuLVlqbzVc7udMDrwetjEv+TZIz1og=
-github.com/gobwas/pool v0.2.1/go.mod h1:q8bcK0KcYlCgd9e7WYLm9LpyS+YeLd8JVDW6WezmKEw=
-github.com/gobwas/ws v1.4.0 h1:CTaoG1tojrh4ucGPcoJFiAQUAsEWekEWvLy7GsVNqGs=
-github.com/gobwas/ws v1.4.0/go.mod h1:G3gNqMNtPppf5XUz7O4shetPpcZ1VJ7zt18dlUeakrc=
 github.com/gofrs/flock v0.13.0 h1:95JolYOvGMqeH31+FC7D2+uULf6mG61mEZ/A8dRYMzw=
 github.com/gofrs/flock v0.13.0/go.mod h1:jxeyy9R1auM5S6JYDBhDt+E2TCo7DkratH4Pgi8P+Z0=
 github.com/golang/protobuf v1.5.0/go.mod h1:FsONVRAS9T7sI+LIUmWTfcYkHO4aIWwzhcaSAoJOfIk=
@@ -69,16 +55,12 @@ github.com/kr/pretty v0.3.1 h1:flRD4NNwYAUpkphVc1HcthR4KEIFJ65n8Mw5qdRn3LE=
 github.com/kr/pretty v0.3.1/go.mod h1:hoEshYVHaxMs3cyo3Yncou5ZscifuDolrwPKZanG3xk=
 github.com/kr/text v0.2.0 h1:5Nx0Ya0ZqY2ygV366QzturHI13Jq95ApcVaJBhpS+AY=
 github.com/kr/text v0.2.0/go.mod h1:eLer722TekiGuMkidMxC/pM04lWEeraHUUmBw8l2grE=
-github.com/ledongthuc/pdf v0.0.0-20220302134840-0c2507a12d80 h1:6Yzfa6GP0rIo/kULo2bwGEkFvCePZ3qHDDTC3/J9Swo=
-github.com/ledongthuc/pdf v0.0.0-20220302134840-0c2507a12d80/go.mod h1:imJHygn/1yfhB7XSJJKlFZKl/J+dCPAknuiaGOshXAs=
 github.com/mattn/go-isatty v0.0.20 h1:xfD0iDuEKnDkl03q4limB+vH+GxLEtL/jb4xVJSWWEY=
 github.com/mattn/go-isatty v0.0.20/go.mod h1:W+V8PltTTMOvKvAeJH7IuucS94S2C6jfK/D7dTCTo3Y=
 github.com/mattn/go-sqlite3 v1.14.17 h1:mCRHCLDUBXgpKAqIKsaAaAsrAlbkeomtRFKXh2L6YIM=
 github.com/mattn/go-sqlite3 v1.14.17/go.mod h1:2eHXhiwb8IkHr+BDWZGa96P6+rkvnG63S2DGjv9HUNg=
 github.com/matttproud/golang_protobuf_extensions/v2 v2.0.0 h1:jWpvCLoY8Z/e3VKvlsiIGKtc+UG6U5vzxaoagmhXfyg=
 github.com/matttproud/golang_protobuf_extensions/v2 v2.0.0/go.mod h1:QUyp042oQthUoa9bqDv0ER0wrtXnBruoNd7aNjkbP+k=
-github.com/orisano/pixelmatch v0.0.0-20220722002657-fb0b55479cde h1:x0TT0RDC7UhAVbbWWBzr41ElhJx5tXPWkIHA2HWPRuw=
-github.com/orisano/pixelmatch v0.0.0-20220722002657-fb0b55479cde/go.mod h1:nZgzbfBr3hhjoZnS66nKrHmduYNpc34ny7RK4z5/HM0=
 github.com/pingcap/errors v0.11.4 h1:lFuQV/oaUMGcD2tqt+01ROSmJs75VG1ToEOkZIZ4nE4=
 github.com/pingcap/errors v0.11.4/go.mod h1:Oi8TUi2kEtXXLMJk9l1cGmz20kV3TaQ0usTwv5KuLY8=
 github.com/pkg/errors v0.9.1 h1:FEBLx1zS214owpjy7qsBeixbURkuhQAwrK5UwLGTwt4=
@@ -129,8 +111,8 @@ golang.org/x/mod v0.17.0/go.mod h1:hTbmBsO62+eylJbnUtE2MGJUyE7QWk4xUqPFrRgJ+7c=
 golang.org/x/sync v0.14.0 h1:woo0S4Yywslg6hp4eUFjTVOyKt0RookbpAHG4c1HmhQ=
 golang.org/x/sync v0.14.0/go.mod h1:1dzgHSNfp02xaA81J2MS99Qcpr2w7fw1gpm99rleRqA=
 golang.org/x/sys v0.6.0/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
-golang.org/x/sys v0.47.0 h1:o7XGOvZQCADBQQ4Y7VNq2dRWQR7JmOUW8Kxx4ZsNgWs=
-golang.org/x/sys v0.47.0/go.mod h1:4GL1E5IUh+htKOUEOaiffhrAeqysfVGipDYzABqnCmw=
+golang.org/x/sys v0.37.0 h1:fdNQudmxPjkdUTPnLn5mdQv7Zwvbvpaxqs831goi9kQ=
+golang.org/x/sys v0.37.0/go.mod h1:OgkHotnGiDImocRcuBABYBEXf8A9a87e/uXjp9XT3ks=
 golang.org/x/text v0.25.0 h1:qVyWApTSYLk/drJRO5mDlNYskwQznZmkpV2c8q9zls4=
 golang.org/x/text v0.25.0/go.mod h1:WEdwpYrmk1qmdHvhkSTNPm3app7v4rsT8F2UD6+VHIA=
 golang.org/x/tools v0.21.1-0.20240508182429-e35e4ccd0d2d h1:vU5i/LfpvrRCpgM/VPfJLg5KjxD3E+hfT1SH+d9zLwg=

internal/config/config.go

@@ -75,6 +75,11 @@ const (
 	// internet-exposed endpoint.
 	defaultReceiverRateLimit = 120
 
+	// defaultTrustedProxies is TRUSTED_PROXIES when it is unset: the
+	// RFC 1918 private ranges, which a reverse proxy reaching the
+	// process over a Docker network or a private LAN connects from.
+	defaultTrustedProxies = "10.0.0.0/8,172.16.0.0/12,192.168.0.0/16"
+
 	// maxPort is the highest valid TCP port number. The lower
 	// bound (at least 1) is enforced by envPositiveInt.
 	maxPort = 65535
@@ -172,13 +177,14 @@ type Config struct {
 
 	// TrustedProxies is the set of networks whose members are
 	// allowed to speak for the client with X-Forwarded-For, the
-	// only forwarded header read. It is empty unless
-	// TRUSTED_PROXIES is set, and empty means no peer is
-	// trusted: forwarded headers are then ignored entirely and
-	// clients are identified by the connection's own address.
-	// Members can choose their own rate-limit key, so this must
-	// name proxy hosts only, never a block that also covers
-	// clients.
+	// only forwarded header read. Unless TRUSTED_PROXIES is set it
+	// is the RFC 1918 private ranges (defaultTrustedProxies); a set
+	// value replaces them. If any client can reach the process, or
+	// the proxy in front of it, from an RFC 1918 source address
+	// (directly, or through anything that can rewrite source
+	// addresses, such as NAT or a published container port), it
+	// must be set to the proxy's address alone, or every rate limit
+	// can be bypassed by those clients.
 	TrustedProxies []netip.Prefix
 
 	// AllowedEgressCIDRs is the set of networks a delivery target
@@ -460,14 +466,15 @@ func parseCIDR(entry string) (netip.Prefix, error) {
 
 // envPrefixList returns the value of the named environment variable
 // parsed as a comma-separated list of CIDR blocks (bare addresses
-// allowed). An unset, empty, or blank value yields an empty list. A
-// set value containing an unparseable entry is a hard error naming
-// the key and the bad entry, so startup fails loudly rather than
-// silently running with a list the operator did not intend.
-func envPrefixList(key string) ([]netip.Prefix, error) {
+// allowed). An unset, empty, or blank value is read as defaultValue
+// instead. A set value containing an unparseable entry is a hard
+// error naming the key and the bad entry, so startup fails loudly
+// rather than silently running with a list the operator did not
+// intend.
+func envPrefixList(key, defaultValue string) ([]netip.Prefix, error) {
 	v := strings.TrimSpace(os.Getenv(key))
 	if v == "" {
-		return nil, nil
+		v = defaultValue
 	}
 
 	var prefixes []netip.Prefix
@@ -681,12 +688,12 @@ func loadFromEnv() (*Config, error) {
 		return nil, err
 	}
 
-	trustedProxies, err := envPrefixList("TRUSTED_PROXIES")
+	trustedProxies, err := envPrefixList("TRUSTED_PROXIES", defaultTrustedProxies)
 	if err != nil {
 		return nil, err
 	}
 
-	allowedEgressCIDRs, err := envPrefixList("ALLOWED_EGRESS_CIDRS")
+	allowedEgressCIDRs, err := envPrefixList("ALLOWED_EGRESS_CIDRS", "")
 	if err != nil {
 		return nil, err
 	}
@@ -760,50 +767,6 @@ func (c *Config) warnEgressAllowlist(log *slog.Logger) {
 	)
 }
 
-// warnSharedRateLimitBucket logs a startup warning whenever
-// TRUSTED_PROXIES is empty, in any environment.
-//
-// With no trusted proxies every rate limiter keys on the connecting
-// peer's address. Whether that is harmless or dangerous depends on
-// what is in front of the process, which this code cannot observe:
-// with nothing in front, the peer is the client and the limits are
-// per-client as intended; behind a reverse proxy the peer is the proxy
-// for every request, so all clients share one bucket per limiter.
-//
-// The login endpoint no longer spends budget on arrival — it verifies
-// credentials first and charges only failures — so a shared bucket
-// cannot deny the operator a correct password. What it does collapse
-// is the failure counting: one client's wrong passwords throttle
-// everyone else's wrong passwords, and the receiver's limits become
-// service-wide ceilings.
-//
-// The warning is deliberately not gated on WEBHOOKER_ENVIRONMENT:
-// behind a proxy every client shares one bucket in dev and prod alike.
-//
-// The default of trusting nobody is deliberate — trusting forwarded
-// headers from arbitrary peers lets any client choose its own bucket —
-// so this warns rather than failing startup or changing the key.
-func (c *Config) warnSharedRateLimitBucket(log *slog.Logger) {
-	if len(c.TrustedProxies) > 0 {
-		return
-	}
-
-	log.Warn(
-		"TRUSTED_PROXIES is empty: every rate limit keys on the "+
-			"connecting peer's address. With nothing proxying to "+
-			"this process that is the client itself and the limits "+
-			"are per-client as intended. Behind a reverse proxy the "+
-			"peer is the proxy on every request, so all clients "+
-			"share one bucket per limit: the receiver limits become "+
-			"service-wide ceilings, and one client's failed logins "+
-			"throttle every other client's failed logins — a "+
-			"correct password still gets in. If anything proxies to "+
-			"this process, set TRUSTED_PROXIES to its address.",
-		"environment", c.Environment,
-		"trustedProxies", len(c.TrustedProxies),
-	)
-}
-
 // New creates a Config by reading environment variables.
 //
 //nolint:revive // lc parameter is required by fx even if unused.
@@ -849,7 +812,6 @@ func New(lc fx.Lifecycle, params ConfigParams) (*Config, error) {
 		"hasMetricsAuth", s.MetricsAuthEnabled(),
 	)
 
-	s.warnSharedRateLimitBucket(log)
 	s.warnEgressAllowlist(log)
 
 	return s, nil

internal/config/config_test.go

@@ -551,6 +551,11 @@ func testReceiverRateLimitSuccess(
 }
 
 func TestTrustedProxies(t *testing.T) {
+	// Unset, the RFC 1918 private ranges are trusted, so a reverse
+	// proxy on a Docker network or a private LAN is covered without
+	// configuration.
+	defaultProxies := []string{cidrPrivateV4, "172.16.0.0/12", "192.168.0.0/16"}
+
 	tests := []struct {
 		name        string
 		set         bool
@@ -559,18 +564,21 @@ func TestTrustedProxies(t *testing.T) {
 		expected    []string
 	}{
 		{
-			// The default must be "trust nobody": an empty list
-			// means forwarded headers are ignored, never that
-			// every peer may speak for the client.
 			name:     caseUnsetUsesDefault,
 			set:      false,
-			expected: []string{},
+			expected: defaultProxies,
 		},
 		{
-			name:     "blank value trusts nothing",
+			name:     "blank value uses default",
 			set:      true,
 			value:    "  ",
-			expected: []string{},
+			expected: defaultProxies,
+		},
+		{
+			name:     "set value replaces the default entirely",
+			set:      true,
+			value:    "203.0.113.7",
+			expected: []string{"203.0.113.7/32"},
 		},
 		{
 			name:  caseValidValueParsed,
@@ -845,101 +853,6 @@ func TestEgressAllowlistWarning(t *testing.T) {
 	}
 }
 
-// TestSharedRateLimitBucketWarning covers the startup warning that
-// tells an operator a deployment behind a reverse proxy shares one
-// rate-limit bucket between every client, which turns the receiver
-// limits into service-wide ceilings and collapses login failure
-// counting. It must fire whenever TRUSTED_PROXIES is empty, in any
-// environment, because behind a proxy every client shares one bucket
-// in dev and prod alike. It stays quiet once proxies are named.
-func TestSharedRateLimitBucketWarning(t *testing.T) {
-	tests := []struct {
-		name           string
-		environment    string
-		trustedProxies string
-		expectWarning  bool
-	}{
-		{
-			name:          "prod without trusted proxies warns",
-			environment:   config.EnvironmentProd,
-			expectWarning: true,
-		},
-		{
-			name:           "prod with trusted proxies is quiet",
-			environment:    config.EnvironmentProd,
-			trustedProxies: cidrPrivateV4,
-			expectWarning:  false,
-		},
-		{
-			name:          "dev without trusted proxies warns",
-			environment:   config.EnvironmentDev,
-			expectWarning: true,
-		},
-		{
-			name:           "dev with trusted proxies is quiet",
-			environment:    config.EnvironmentDev,
-			trustedProxies: cidrPrivateV4,
-			expectWarning:  false,
-		},
-	}
-
-	for _, tt := range tests {
-		t.Run(tt.name, func(t *testing.T) {
-			// Cannot use t.Parallel() here because t.Setenv
-			// is incompatible with parallel subtests.
-			t.Setenv("WEBHOOKER_ENVIRONMENT", tt.environment)
-
-			if tt.trustedProxies == "" {
-				require.NoError(
-					t, os.Unsetenv("TRUSTED_PROXIES"),
-				)
-			} else {
-				t.Setenv("TRUSTED_PROXIES", tt.trustedProxies)
-			}
-
-			var buf bytes.Buffer
-
-			log := slog.New(slog.NewJSONHandler(
-				&buf, &slog.HandlerOptions{
-					Level: slog.LevelDebug,
-				},
-			))
-
-			require.NoError(
-				t,
-				config.WarnSharedRateLimitBucketForTest(log),
-			)
-
-			if !tt.expectWarning {
-				assert.Empty(t, buf.String())
-
-				return
-			}
-
-			logged := buf.String()
-
-			assert.Contains(t, logged, `"level":"WARN"`)
-			assert.Contains(t, logged, "TRUSTED_PROXIES")
-			assert.Contains(t, logged, "share one bucket")
-			assert.Contains(
-				t, logged, "throttle every other client's failed logins",
-			)
-			// The warning must not claim a lockout the login
-			// endpoint no longer permits: credentials are verified
-			// before any budget is spent.
-			assert.Contains(
-				t, logged, "a correct password still gets in",
-			)
-			// The text must stay accurate for a developer with
-			// nothing in front of the process, where an empty
-			// list costs nothing.
-			assert.Contains(
-				t, logged, "nothing proxying to this process",
-			)
-		})
-	}
-}
-
 // metricsEnv describes what one subtest below puts in the
 // environment for a single METRICS_ variable. A variable that is
 // set to the empty string and one that is not set at all are

internal/config/export_test.go

@@ -6,21 +6,6 @@ import "log/slog"
 // the external config_test package so each helper can be covered by
 // its own table-driven test without weakening the package API.
 
-// WarnSharedRateLimitBucketForTest loads a Config from the current
-// environment and emits its startup warnings to log. The real logger
-// writes to stdout, so this lets the warning's firing condition be
-// asserted against a handler the test controls.
-func WarnSharedRateLimitBucketForTest(log *slog.Logger) error {
-	c, err := loadFromEnv()
-	if err != nil {
-		return err
-	}
-
-	c.warnSharedRateLimitBucket(log)
-
-	return nil
-}
-
 // WarnEgressAllowlistForTest loads a Config from the current
 // environment and emits its egress-allowlist startup warning to
 // log, so a test can assert both that the warning fires only when

internal/handlers/auth.go

@@ -103,9 +103,10 @@ func (h *Handlers) renderLoginError(
 // The credential check runs BEFORE any rate-limit budget is
 // consulted, and only a failed check spends budget. That is what
 // keeps the single administrative path reachable: behind the reverse
-// proxy this deployment requires, with TRUSTED_PROXIES unset, every
-// client shares one bucket, so a limiter spent on arrival lets any
-// stranger deny the operator's own correct password indefinitely.
+// proxy this deployment requires, when TRUSTED_PROXIES does not cover
+// it, every client shares one bucket, so a limiter spent on arrival
+// lets any stranger deny the operator's own correct password
+// indefinitely.
 //
 // Verifying first means every login POST costs an Argon2id hash, so
 // the work is taken under a bounded number of verification slots.

internal/handlers/auth_test.go

@@ -25,7 +25,7 @@ const (
 
 	// sharedProxyPeer is the whole point of this file. Production is
 	// required to run behind a TLS-terminating reverse proxy, and
-	// TRUSTED_PROXIES defaults to empty, so every client — attacker
+	// when TRUSTED_PROXIES does not cover it every client — attacker
 	// and operator alike — reaches the process from the proxy's
 	// address and shares one rate-limit bucket. Both parties in
 	// these tests therefore use the same RemoteAddr.
@@ -115,11 +115,11 @@ func floodFailures(
 // done-criterion of https://git.eeqj.de/sneak/webhooker/issues/150.
 //
 // The attacker and the operator share one rate-limit bucket, because
-// behind the mandated reverse proxy with TRUSTED_PROXIES unset every
-// client keys on the proxy's address. The attacker floods the
-// operator's own username — a single-admin product has a predictable
-// one — far past the failure limit. The operator must still be able
-// to log in with the correct password.
+// behind the mandated reverse proxy, when TRUSTED_PROXIES does not
+// cover it, every client keys on the proxy's address. The attacker
+// floods the operator's own username — a single-admin product has a
+// predictable one — far past the failure limit. The operator must
+// still be able to log in with the correct password.
 //
 // This fails if credentials stop being verified ahead of the limiter.
 func TestLogin_StrangersFloodCannotLockOutTheOperator(t *testing.T) {

internal/middleware/loginguard.go

@@ -108,10 +108,10 @@ type failureWindow struct {
 //
 // A limiter that spends budget on arrival cannot protect a
 // single-admin product: behind the reverse proxy the deployment
-// requires, with TRUSTED_PROXIES unset, every client keys on the
-// proxy, so a stranger trickling five POSTs a minute keeps the one
-// bucket full and the operator's own correct password is answered 429
-// forever. There is no second administrative path.
+// requires, when TRUSTED_PROXIES does not cover it, every client
+// keys on the proxy, so a stranger trickling five POSTs a minute
+// keeps the one bucket full and the operator's own correct password
+// is answered 429 forever. There is no second administrative path.
 //
 // So budget is spent only by a FAILED verification. A correct
 // password is never throttled, whatever the counters say, which is

internal/middleware/ratelimit.go

@@ -123,9 +123,8 @@ func bucketKey(addr netip.Addr) string {
 	return prefix.String()
 }
 
-// isTrustedProxy reports whether addr belongs to a network the
-// operator listed in TRUSTED_PROXIES. The list is empty by default,
-// so by default nothing is trusted.
+// isTrustedProxy reports whether addr belongs to a network in
+// TRUSTED_PROXIES, which by default is the RFC 1918 private ranges.
 func (m *Middleware) isTrustedProxy(addr netip.Addr) bool {
 	for _, prefix := range m.params.Config.TrustedProxies {
 		if prefix.Contains(addr) {

internal/middleware/ratelimit_test.go

@@ -384,8 +384,8 @@ const (
 	// trustedProxyCIDR is the proxy network the forwarded-path
 	// tests configure, and trustedPeer an address inside it. A
 	// production deployment is required to run behind a reverse
-	// proxy with TRUSTED_PROXIES set, so this is the shape the
-	// bucketing has to hold in.
+	// proxy that TRUSTED_PROXIES covers, either by the default or by
+	// a set value, so this is the shape the bucketing has to hold in.
 	trustedProxyCIDR = "10.0.0.0/8"
 	trustedPeer      = "10.0.0.1:44444"
 )
@@ -426,8 +426,8 @@ func assertSharedBucket(
 }
 
 // TestRateLimitKey_SpoofedForwardedFromUntrustedPeer is the test
-// this gating exists for: with no trusted proxies configured (the
-// default), a client that rotates a forwarded header on every
+// this gating exists for: from a peer that is not a trusted
+// proxy, a client that rotates a forwarded header on every
 // request must stay in one bucket. If forwarded headers were
 // trusted unconditionally, each spoofed value would mint a fresh
 // bucket and the limit would stop no one.
@@ -1097,8 +1097,9 @@ func TestPostRateLimit_IPv4IndependentPerAddress(t *testing.T) {
 // that arrives from trustedPeer — a configured trusted proxy — and
 // names forwarded as its client in X-Forwarded-For. That is the
 // production path: a deployment is required to run behind a reverse
-// proxy with TRUSTED_PROXIES set, so the forwarded address, not the
-// peer, is what the limiters bucket on there.
+// proxy that TRUSTED_PROXIES covers, either by the default or by a
+// set value, so the forwarded address, not the peer, is what the
+// limiters bucket on there.
 func forwardedKeyFor(
 	t *testing.T, m *middleware.Middleware, forwarded string,
 ) string {
@@ -1178,9 +1179,9 @@ func TestRateLimitKey_ForwardedIPv6BucketsByPrefix(t *testing.T) {
 //
 // Every existing test of this fallback uses an IPv4 proxy, where
 // bucketKey is the identity function, so replacing the call with
-// peer.String() leaves the whole suite green. Only operator-listed
-// addresses reach this line and the fallback is fail-closed, so this
-// pins behaviour rather than fixing a defect.
+// peer.String() leaves the whole suite green. Only addresses inside
+// TRUSTED_PROXIES reach this line and the fallback is fail-closed, so
+// this pins behaviour rather than fixing a defect.
 func TestRateLimitKey_TrustedPeerUnusableForwardedMasksPeer(
 	t *testing.T,
 ) {

internal/server/alpine_browser_test.go

@@ -1,276 +0,0 @@
-package server_test
-
-import (
-	"context"
-	"fmt"
-	"net/http"
-	"net/http/httptest"
-	"os/exec"
-	"slices"
-	"strings"
-	"sync"
-	"testing"
-	"time"
-
-	"github.com/chromedp/cdproto/network"
-	"github.com/chromedp/cdproto/runtime"
-	"github.com/chromedp/chromedp"
-	"github.com/stretchr/testify/assert"
-	"github.com/stretchr/testify/require"
-)
-
-const (
-	// browserTimeout bounds everything one test does in the browser.
-	browserTimeout = 60 * time.Second
-
-	// settleTimeout bounds the wait for an element to show or hide.
-	settleTimeout = 5 * time.Second
-)
-
-// TestAlpineRunsUnderTheSecurityPolicy loads the webhook page and the
-// event log in headless Chromium, served by the real router and so
-// under the real Content-Security-Policy, and checks that the pages'
-// Alpine.js directives work.
-func TestAlpineRunsUnderTheSecurityPolicy(t *testing.T) {
-	t.Parallel()
-
-	ctx, consoleProblems := startBrowser(t)
-
-	env := newTestEnv(t)
-	srv := httptest.NewServer(env.router)
-	t.Cleanup(srv.Close)
-
-	userID, _ := env.seedUser(t, "browser", "browser-password")
-	webhook := env.seedWebhook(t, userID)
-	event := env.seedEvent(t, webhook.ID, `{"hello":"browser"}`)
-
-	require.NoError(t, chromedp.Run(
-		ctx, setCookies(srv.URL, env.authCookies(t, userID, "browser")),
-	))
-
-	checkAddForms(ctx, t, srv.URL+"/source/"+webhook.ID)
-	checkTargetType(ctx, t)
-	checkEventToggle(
-		ctx, t, srv.URL+"/source/"+webhook.ID+"/logs", event.ID,
-	)
-
-	assert.Empty(
-		t, consoleProblems(),
-		"the pages printed console warnings, errors or exceptions",
-	)
-}
-
-// startBrowser starts headless Chromium for one test. It returns the
-// context that drives it, and a function listing every console warning
-// or error and every uncaught exception its pages raised: that is how
-// Alpine.js reports an expression it cannot run.
-//
-// The test is skipped when chromium is not on PATH. The Dockerfile's
-// test stage installs it, so the image build always runs this check.
-func startBrowser(t *testing.T) (context.Context, func() []string) {
-	t.Helper()
-
-	path, err := exec.LookPath("chromium")
-	if err != nil {
-		t.Skipf("chromium is not installed: %v", err)
-	}
-
-	allocCtx, cancelAlloc := chromedp.NewExecAllocator(
-		t.Context(),
-		append(
-			chromedp.DefaultExecAllocatorOptions[:],
-			chromedp.ExecPath(path),
-			// The image build runs tests as root, where Chromium's
-			// sandbox cannot start.
-			chromedp.NoSandbox,
-		)...,
-	)
-	t.Cleanup(cancelAlloc)
-
-	ctx, cancel := chromedp.NewContext(allocCtx)
-	t.Cleanup(cancel)
-
-	ctx, cancelTimeout := context.WithTimeout(ctx, browserTimeout)
-	t.Cleanup(cancelTimeout)
-
-	var (
-		mu       sync.Mutex
-		problems []string
-	)
-
-	chromedp.ListenTarget(ctx, func(ev any) {
-		var problem string
-
-		switch ev := ev.(type) {
-		case *runtime.EventConsoleAPICalled:
-			if ev.Type != runtime.APITypeWarning &&
-				ev.Type != runtime.APITypeError {
-				return
-			}
-
-			args := make([]string, 0, len(ev.Args))
-			for _, arg := range ev.Args {
-				args = append(args, string(arg.Value))
-			}
-
-			problem = strings.Join(args, " ")
-		case *runtime.EventExceptionThrown:
-			problem = ev.ExceptionDetails.Error()
-		default:
-			return
-		}
-
-		mu.Lock()
-		defer mu.Unlock()
-
-		problems = append(problems, problem)
-	})
-
-	return ctx, func() []string {
-		mu.Lock()
-		defer mu.Unlock()
-
-		return slices.Clone(problems)
-	}
-}
-
-// setCookies gives the browser the cookies for the server at base.
-func setCookies(base string, cookies []*http.Cookie) chromedp.ActionFunc {
-	return chromedp.ActionFunc(func(ctx context.Context) error {
-		for _, c := range cookies {
-			err := network.SetCookie(c.Name, c.Value).
-				WithURL(base).
-				Do(ctx)
-			if err != nil {
-				return fmt.Errorf("set cookie %s: %w", c.Name, err)
-			}
-		}
-
-		return nil
-	})
-}
-
-// loadPage opens url and waits for Alpine.js to start, which it does
-// by removing every x-cloak attribute. Until then x-cloak hides the
-// elements Alpine would hide, so a check made earlier proves nothing.
-func loadPage(url string) chromedp.Tasks {
-	return chromedp.Tasks{
-		chromedp.Navigate(url),
-		chromedp.WaitNotPresent("[x-cloak]", chromedp.ByQuery),
-	}
-}
-
-// shown waits up to settleTimeout for the first element matching a CSS
-// selector to be rendered, and reports whether it was. The wait is
-// needed because Alpine.js shows an element on the next animation
-// frame, not at once.
-func shown(ctx context.Context, selector string) bool {
-	ctx, cancel := context.WithTimeout(ctx, settleTimeout)
-	defer cancel()
-
-	return chromedp.Run(
-		ctx, chromedp.WaitVisible(selector, chromedp.ByQuery),
-	) == nil
-}
-
-// hidden is shown's opposite: it waits for the element to be hidden.
-func hidden(ctx context.Context, selector string) bool {
-	ctx, cancel := context.WithTimeout(ctx, settleTimeout)
-	defer cancel()
-
-	return chromedp.Run(
-		ctx, chromedp.WaitNotVisible(selector, chromedp.ByQuery),
-	) == nil
-}
-
-// click clicks the first element matching an XPath expression.
-func click(ctx context.Context, t *testing.T, xpath string) {
-	t.Helper()
-
-	require.NoError(t, chromedp.Run(
-		ctx, chromedp.Click(xpath, chromedp.BySearch),
-	))
-}
-
-// checkAddForms loads a webhook page and checks that each section's add
-// form stays hidden until the Add button beside its heading is clicked.
-func checkAddForms(ctx context.Context, t *testing.T, url string) {
-	t.Helper()
-
-	require.NoError(t, chromedp.Run(ctx, loadPage(url)))
-
-	sections := []struct{ heading, form string }{
-		{"Entrypoints", `form[action$="/entrypoints"]`},
-		{"Targets", `form[action$="/targets"]`},
-	}
-
-	for _, s := range sections {
-		assert.Truef(
-			t, hidden(ctx, s.form),
-			"%s: the add form shows before Add is clicked", s.heading,
-		)
-
-		click(ctx, t, `//h2[text()="`+s.heading+
-			`"]/following-sibling::button`)
-
-		assert.Truef(
-			t, shown(ctx, s.form),
-			"%s: the add form stays hidden when Add is clicked", s.heading,
-		)
-	}
-}
-
-// checkTargetType chooses Slack in the open add target form and checks
-// what the form would then submit: one url field, the Slack one, and
-// not the HTTP url, headers or timeout, which are hidden and disabled.
-func checkTargetType(ctx context.Context, t *testing.T) {
-	t.Helper()
-
-	const (
-		chooseSlack = `(() => {
-			const type = document.querySelector('select[name="type"]');
-			type.value = "slack";
-			type.dispatchEvent(new Event("change"));
-		})()`
-		submitted = `[...new FormData(
-			document.querySelector('form[action$="/targets"]')).keys()]`
-	)
-
-	var fields []string
-
-	require.NoError(t, chromedp.Run(
-		ctx,
-		chromedp.Evaluate(chooseSlack, nil),
-		chromedp.Evaluate(submitted, &fields),
-	))
-
-	assert.Equal(
-		t,
-		[]string{"csrf_token", "name", "type", "max_retries", "url"},
-		fields,
-		"with Slack chosen, the HTTP fields must not be submitted",
-	)
-}
-
-// checkEventToggle loads the event log and checks that clicking an
-// event's row expands it and clicking again collapses it.
-func checkEventToggle(
-	ctx context.Context, t *testing.T, url, eventID string,
-) {
-	t.Helper()
-
-	// The row shows the event's ID; its Resubmit form is in the part
-	// that expands.
-	row := `//span[text()="` + eventID + `"]`
-	expanded := `form[action$="/resubmit"]`
-
-	require.NoError(t, chromedp.Run(ctx, loadPage(url)))
-
-	assert.True(t, hidden(ctx, expanded), "the event starts expanded")
-
-	click(ctx, t, row)
-	assert.True(t, shown(ctx, expanded), "clicking the event does not expand it")
-
-	click(ctx, t, row)
-	assert.True(t, hidden(ctx, expanded), "clicking it again does not collapse it")
-}

internal/server/routes.go

@@ -154,11 +154,12 @@ func (s *Server) setupPageRoutes() {
 		r.Use(s.mw.NoCache())
 
 		// The login POST carries no pre-emptive rate limiter. Behind
-		// the reverse proxy production requires, with TRUSTED_PROXIES
-		// unset, every client shares one bucket, so a limiter spent
-		// on arrival lets any stranger deny the operator the only
-		// administrative path. The handler verifies credentials first
-		// and charges only failures; see Handlers.authenticateUser.
+		// the reverse proxy production requires, when TRUSTED_PROXIES
+		// does not cover it, every client shares one bucket, so a
+		// limiter spent on arrival lets any stranger deny the operator
+		// the only administrative path. The handler verifies
+		// credentials first and charges only failures; see
+		// Handlers.authenticateUser.
 		r.Get("/login", s.h.HandleLoginPage())
 		r.Post("/login", s.h.HandleLoginSubmit())
 

script/assets

@@ -1,16 +1,15 @@
 #!/bin/sh
 # script/assets: extract Alpine.js from its npm package tarball, committed
-# in 3p/, to static/js/alpine.min.js, where go:embed reads it. The package
-# is @alpinejs/csp, Alpine's build for pages whose Content-Security-Policy
-# forbids eval. The extracted file is not committed. script/test, make
-# build and make dev run this first.
+# in 3p/, to static/js/alpine.min.js, where go:embed reads it. The
+# extracted file is not committed. script/test, make build and make dev run
+# this first.
 set -eu
 
 ROOT="$(cd "$(dirname "$0")/.." && pwd -P)"
 
 main() {
     cd "$ROOT"
-    tar -xzOf 3p/alpinejs-csp-3.14.9.tgz package/dist/cdn.min.js \
+    tar -xzOf 3p/alpinejs-3.14.9.tgz package/dist/cdn.min.js \
         >static/js/alpine.min.js
 }
 

static/js/app.js

@@ -57,62 +57,3 @@
         init();
     }
 })();
-
-// Alpine.js components.
-//
-// The pages' Content-Security-Policy forbids eval, so the UI loads
-// Alpine's CSP build, which cannot run expressions written in the
-// markup: a directive in templates/ may only name a property or method,
-// and each x-data names a component registered here. This script runs
-// before Alpine, whose script tag is deferred, so this listener is in
-// place when Alpine starts.
-document.addEventListener("alpine:init", function () {
-    "use strict";
-
-    // Something a click shows and hides: the mobile menu, an add form,
-    // an event in the event log, a delivery's attempts.
-    window.Alpine.data("collapsible", function () {
-        return {
-            open: false,
-            toggle() {
-                this.open = !this.open;
-            },
-            get closed() {
-                return !this.open;
-            },
-            // Turns a downward caret up while open.
-            get caretClass() {
-                return { "rotate-180": this.open };
-            },
-        };
-    });
-
-    // The add target form. Only the chosen type's fields show, and the
-    // others are disabled so that the form does not submit them.
-    window.Alpine.data("targetForm", function () {
-        return {
-            targetType: "http",
-            chooseType(event) {
-                this.targetType = event.target.value;
-            },
-            get isHttp() {
-                return this.targetType === "http";
-            },
-            get isSlack() {
-                return this.targetType === "slack";
-            },
-            get isDatabase() {
-                return this.targetType === "database";
-            },
-            get notHttp() {
-                return !this.isHttp;
-            },
-            get notSlack() {
-                return !this.isSlack;
-            },
-            get notDatabase() {
-                return !this.isDatabase;
-            },
-        };
-    });
-});

templates/navbar.html

@@ -1,14 +1,14 @@
 {{define "navbar"}}
-<nav class="app-bar" x-data="collapsible">
+<nav class="app-bar" x-data="{ open: false }">
     <div class="max-w-6xl mx-auto flex justify-between items-center">
         <div class="flex items-center gap-3">
             <a href="/" class="text-xl font-medium text-gray-900 hover:text-primary-600 transition-colors">Webhooker</a>
         </div>
 
         <!-- Mobile menu button -->
-        <button @click="toggle" class="md:hidden p-2 rounded-md text-gray-500 hover:bg-gray-100">
+        <button @click="open = !open" class="md:hidden p-2 rounded-md text-gray-500 hover:bg-gray-100">
             <svg class="w-6 h-6" fill="none" stroke="currentColor" viewBox="0 0 24 24">
-                <path x-show="closed" stroke-linecap="round" stroke-linejoin="round" stroke-width="2" d="M4 6h16M4 12h16M4 18h16"/>
+                <path x-show="!open" stroke-linecap="round" stroke-linejoin="round" stroke-width="2" d="M4 6h16M4 12h16M4 18h16"/>
                 <path x-show="open" x-cloak stroke-linecap="round" stroke-linejoin="round" stroke-width="2" d="M6 18L18 6M6 6l12 12"/>
             </svg>
         </button>

templates/source_detail.html

@@ -3,7 +3,7 @@
 {{define "title"}}{{.Webhook.Name}} - Webhooker{{end}}
 
 {{define "content"}}
-<div class="max-w-6xl mx-auto px-6 py-8">
+<div class="max-w-6xl mx-auto px-6 py-8" x-data="{ showAddEntrypoint: false, showAddTarget: false }">
     <div class="mb-6">
         <a href="/sources" class="text-sm text-primary-600 hover:text-primary-700">&larr; Back to webhooks</a>
         <div class="flex justify-between items-center mt-2">
@@ -26,10 +26,10 @@
 
     <div class="grid grid-cols-1 lg:grid-cols-2 gap-6">
         <!-- Entrypoints -->
-        <div class="card" x-data="collapsible">
+        <div class="card">
             <div class="p-4 border-b border-gray-200 flex justify-between items-center">
                 <h2 class="text-lg font-medium text-gray-900">Entrypoints</h2>
-                <button @click="toggle" class="btn-text text-sm">
+                <button @click="showAddEntrypoint = !showAddEntrypoint" class="btn-text text-sm">
                     <svg class="w-4 h-4 mr-1" fill="none" stroke="currentColor" viewBox="0 0 24 24">
                         <path stroke-linecap="round" stroke-linejoin="round" stroke-width="2" d="M12 4v16m8-8H4"/>
                     </svg>
@@ -38,7 +38,7 @@
             </div>
 
             <!-- Add entrypoint form -->
-            <div x-show="open" x-cloak class="p-4 bg-gray-50 border-b border-gray-200">
+            <div x-show="showAddEntrypoint" x-cloak class="p-4 bg-gray-50 border-b border-gray-200">
                 <form method="POST" action="/source/{{.Webhook.ID}}/entrypoints" class="flex gap-2">
                     <input type="hidden" name="csrf_token" value="{{.CSRFToken}}">
                     <input type="text" name="description" placeholder="Description (optional)" class="input text-sm flex-1">
@@ -85,10 +85,10 @@
         </div>
 
         <!-- Targets -->
-        <div class="card" x-data="collapsible">
+        <div class="card">
             <div class="p-4 border-b border-gray-200 flex justify-between items-center">
                 <h2 class="text-lg font-medium text-gray-900">Targets</h2>
-                <button @click="toggle" class="btn-text text-sm">
+                <button @click="showAddTarget = !showAddTarget" class="btn-text text-sm">
                     <svg class="w-4 h-4 mr-1" fill="none" stroke="currentColor" viewBox="0 0 24 24">
                         <path stroke-linecap="round" stroke-linejoin="round" stroke-width="2" d="M12 4v16m8-8H4"/>
                     </svg>
@@ -97,42 +97,42 @@
             </div>
 
             <!-- Add target form -->
-            <div x-show="open" x-cloak class="p-4 bg-gray-50 border-b border-gray-200">
-                <form method="POST" action="/source/{{.Webhook.ID}}/targets" x-data="targetForm" class="space-y-3">
+            <div x-show="showAddTarget" x-cloak class="p-4 bg-gray-50 border-b border-gray-200">
+                <form method="POST" action="/source/{{.Webhook.ID}}/targets" x-data="{ targetType: 'http' }" class="space-y-3">
                     <input type="hidden" name="csrf_token" value="{{.CSRFToken}}">
                     <div class="flex gap-2">
                         <input type="text" name="name" placeholder="Target name" required class="input text-sm flex-1">
-                        <select name="type" @change="chooseType" class="input text-sm w-32">
+                        <select name="type" x-model="targetType" class="input text-sm w-32">
                             <option value="http">HTTP</option>
                             <option value="slack">Slack</option>
                             <option value="database">Database</option>
                             <option value="log">Log</option>
                         </select>
                     </div>
-                    <div x-show="isHttp">
-                        <input type="url" name="url" placeholder="https://example.com/webhook" :disabled="notHttp" class="input text-sm">
+                    <div x-show="targetType === 'http'">
+                        <input type="url" name="url" placeholder="https://example.com/webhook" :disabled="targetType !== 'http'" class="input text-sm">
                     </div>
-                    <div x-show="isHttp">
-                        <textarea name="headers" rows="3" placeholder="Authorization: Bearer ..." :disabled="notHttp" class="input text-sm"></textarea>
+                    <div x-show="targetType === 'http'">
+                        <textarea name="headers" rows="3" placeholder="Authorization: Bearer ..." :disabled="targetType !== 'http'" class="input text-sm"></textarea>
                         <p class="text-xs text-gray-500 mt-1">Optional request headers, one <code>Name: value</code> per line, sent with every delivery.</p>
                     </div>
-                    <div x-show="isHttp" class="flex gap-2 items-center">
+                    <div x-show="targetType === 'http'" class="flex gap-2 items-center">
                         <label class="text-sm text-gray-700">Timeout (seconds, blank = default):</label>
-                        <input type="number" name="timeout" min="0" max="300" :disabled="notHttp" class="input text-sm w-24">
+                        <input type="number" name="timeout" min="0" max="300" :disabled="targetType !== 'http'" class="input text-sm w-24">
                     </div>
-                    <div x-show="isHttp">
+                    <div x-show="targetType === 'http'">
                         <div class="flex gap-2 items-center">
                             <label class="text-sm text-gray-700">Max retries:</label>
                             <input type="number" name="max_retries" value="0" min="0" max="20" class="input text-sm w-24">
                         </div>
                         <p class="text-xs text-gray-500 mt-1">This is the total number of delivery attempts, not retries on top of the first: a value of 3 makes three attempts in all. 0 means a single attempt with no retries and no circuit breaker.</p>
                     </div>
-                    <div x-show="isSlack">
-                        <input type="url" name="url" placeholder="https://hooks.slack.com/services/..." :disabled="notSlack" class="input text-sm">
+                    <div x-show="targetType === 'slack'">
+                        <input type="url" name="url" placeholder="https://hooks.slack.com/services/..." :disabled="targetType !== 'slack'" class="input text-sm">
                         <p class="text-xs text-gray-500 mt-1">Slack or Mattermost incoming webhook URL. Payloads are pretty-printed in code blocks.</p>
                     </div>
-                    <div x-show="isDatabase">
-                        <input type="text" name="expiry" placeholder="never" :disabled="notDatabase" class="input text-sm">
+                    <div x-show="targetType === 'database'">
+                        <input type="text" name="expiry" placeholder="never" :disabled="targetType !== 'database'" class="input text-sm">
                         <p class="text-xs text-gray-500 mt-1">Archive expiry: "never" (default) keeps rows forever, or a duration like "720h" prunes older rows.</p>
                     </div>
                     <button type="submit" class="btn-primary text-sm">Add Target</button>

templates/source_logs.html

@@ -23,8 +23,8 @@
     <div class="card">
         <div class="divide-y divide-gray-100">
             {{range .Events}}
-            <div class="p-4" x-data="collapsible">
-                <div class="flex items-center justify-between cursor-pointer" @click="toggle">
+            <div class="p-4" x-data="{ open: false }">
+                <div class="flex items-center justify-between cursor-pointer" @click="open = !open">
                     <div class="flex items-center gap-3">
                         <span class="badge-info">{{.Method}}</span>
                         <span class="text-sm font-mono text-gray-700">{{.ID}}</span>
@@ -43,7 +43,7 @@
                         </span>
                         {{end}}
                         <span class="text-xs text-gray-400">{{.CreatedAt.Format "2006-01-02 15:04:05"}}</span>
-                        <svg class="w-4 h-4 text-gray-400 transition-transform" :class="caretClass" fill="none" stroke="currentColor" viewBox="0 0 24 24">
+                        <svg class="w-4 h-4 text-gray-400 transition-transform" :class="{ 'rotate-180': open }" fill="none" stroke="currentColor" viewBox="0 0 24 24">
                             <path stroke-linecap="round" stroke-linejoin="round" stroke-width="2" d="M19 9l-7 7-7-7"/>
                         </svg>
                     </div>
@@ -71,8 +71,8 @@
                         <h3 class="text-xs font-medium uppercase tracking-wide text-gray-500">Deliveries</h3>
                         <div class="mt-2 divide-y divide-gray-200">
                             {{range .Deliveries}}
-                            <div class="py-2" x-data="collapsible">
-                                <div class="flex items-center justify-between cursor-pointer" @click="toggle">
+                            <div class="py-2" x-data="{ attempts: false }">
+                                <div class="flex items-center justify-between cursor-pointer" @click="attempts = !attempts">
                                     <div class="flex items-center gap-3">
                                         <span class="text-sm text-gray-700">{{.Target.DisplayName}}</span>
                                         <span class="text-xs {{if eq .Status "delivered"}}text-green-600{{else if eq .Status "failed"}}text-red-600{{else if eq .Status "retrying"}}text-yellow-600{{else}}text-gray-400{{end}}">{{.Status}}</span>
@@ -86,13 +86,13 @@
                                         </form>
                                         {{end}}
                                         <span class="text-xs text-gray-400">{{.AttemptCount}} attempt{{if ne .AttemptCount 1}}s{{end}}</span>
-                                        <svg class="w-3 h-3 text-gray-400 transition-transform" :class="caretClass" fill="none" stroke="currentColor" viewBox="0 0 24 24">
+                                        <svg class="w-3 h-3 text-gray-400 transition-transform" :class="{ 'rotate-180': attempts }" fill="none" stroke="currentColor" viewBox="0 0 24 24">
                                             <path stroke-linecap="round" stroke-linejoin="round" stroke-width="2" d="M19 9l-7 7-7-7"/>
                                         </svg>
                                     </div>
                                 </div>
 
-                                <div x-show="open" x-cloak class="mt-2 space-y-2">
+                                <div x-show="attempts" x-cloak class="mt-2 space-y-2">
                                     {{if .AttemptsOmitted}}
                                     <p class="text-xs text-gray-500">{{.AttemptsOmitted}} attempt{{if ne .AttemptsOmitted 1}}s{{end}} omitted between the first and last shown.</p>
                                     {{end}}