v0.26.2 http sink backlog for late streams, web updates

doc/cli.md

@@ -177,7 +177,8 @@ unknown key fails and lists the valid ones. A `path` is a file, a directory
 - `tail`: follow files to stdout, like `tail -F`
   - `path` (required), `from`, `format` (`raw`)
 - `serve`: a live stream, an [http sink](sinks.md#http): a browser at
-  `listen` gets the viewer, `/stream` is SSE
+  `listen` gets the viewer, `/stream` is SSE, each stream starting with the
+  last 1000 entries
   - `path`, `from`, `format` (`json`), `listen` (`127.0.0.1:8080`)
   - `tls`: `off` (default), `self` (a self-signed certificate made at
     startup), `issuer` (one signed by `issuer_cert` and `issuer_key`), or

doc/lw.1

@@ -304,7 +304,8 @@ Follow files to standard output, like
 .It Cm serve Oo Cm path , listen , format , tls , users , proxy , viewer , allow , deny Oc
 Serve a live HTTP stream on
 .Cm listen
-.Pq default Li 127.0.0.1:8080 .
+.Pq default Li 127.0.0.1:8080 ,
+each stream starting with the last 1000 entries.
 .Cm tls
 is
 .Cm off ,

doc/sinks.md

@@ -170,6 +170,9 @@ Options, each as type and default:
 - `client_buffer_size` (int, `256`): per-client send queue depth.
 - `write_timeout_ms` (int, `0`): per-event write deadline; `0` = none.
 - `max_connections` (int, `0`): concurrent stream cap; `0` = unlimited.
+- `replay_lines` (int, `0`; `1000` from the `serve` preset): the last entries
+  a new stream gets after its `connected` event, before the live ones, so a
+  browser opened late sees a backlog; `0` = none.
 - `login_page` (bool, `false`): `scram` in proxy mode only (an error
   elsewhere): the browser login page at `/auth/login`.
 - `viewer_page` (bool, `false`): `scram` in proxy mode only (an error
@@ -212,8 +215,8 @@ Options, each as type and default:
   - never under `scram` on the sink's own TLS, which a browser cannot log in
     to: `/` is refused like any other path;
   - an endpoint at `/` keeps the root, and the viewer stays at `/auth/view`.
-  The viewer shows entries from when it connects (the sink keeps no backlog)
-  and holds one stream against `max_connections`.
+  The viewer starts with the `replay_lines` backlog, holds one stream against
+  `max_connections`, and says so when all are taken (`server full`).
 - Refusals are logged at WARN and counted in `auth_rejected`. The authorized
   identity is recorded in the client's session as `auth_method` /
   `auth_identity`.

doc/todo.md

@@ -65,16 +65,11 @@ identity, and both skeletons download the tagged source.
 
 Smaller items found along the way, each independent of the others.
 
-1. A late browser sees no backlog: the `http` sink keeps none, so the viewer
-   shows entries from when it connects. A bounded replay (a `replay_lines`
-   option, sent after `event: connected`) would fill it. The viewer also hides
-   a `503` from `max_connections` behind "retrying"; the status JSON it already
-   fetches could name it.
-2. Level detection. `source.ExtractLogLevel` needs a delimiter after the name
+1. Level detection. `source.ExtractLogLevel` needs a delimiter after the name
    (`ERROR:`, `[WARN]`, ` INFO `), so `warning disk full` or `DBG x` get no
    level, hence no color. Match the names as words, as the console sink's
    painter does, with one table for both.
-3. Command line:
+2. Command line:
    - a positional word at the top level (`lw tail`, `lw -t FILE`) still reaches
      config with an unclear message; name it ("unexpected argument X; the file
      is -c FILE");
@@ -84,11 +79,9 @@ Smaller items found along the way, each independent of the others.
    - `lw tls cert --host` could become `--hosts` (keeping `--host`), to match
      `tls.hosts` and the preset key;
    - top-level usage errors exit 1, subcommand ones 2.
-4. `GET /favicon.ico` answers 404; the logo could serve as the icon once the
-   pages' CSP allows `img-src 'self'`.
-5. TLS: the generated-certificate key is one per process, so a pin taken from a
+3. TLS: the generated-certificate key is one per process, so a pin taken from a
    `self_signed` listener also matches an `issuer` listener of the same
    process; document it or key per listener. Pins are checked in
    `VerifyPeerCertificate`, which Go skips on resumption: guard it if a dialer
    ever keeps a `ClientSessionCache`.
-6. `core.ShutdownTimeout` is unused.
+4. `core.ShutdownTimeout` is unused.