v0.26.3 web viewer improvement

doc/architecture.md

@@ -83,7 +83,8 @@ registry rejects a second instance of any such type.
 - `Node`: origin node label for chained topologies; stamped at the first hop,
   preserved by relays.
 - `Source`: origin identifier within the node (filename, plugin id, …).
-- `Level`: `DEBUG`, `INFO`, `WARN`, `ERROR` or `TRACE`, when detected.
+- `Level`: `TRACE`, `DEBUG`, `INFO`, `WARN` or `ERROR`, when detected; the
+  words naming each are one table, `core.Levels`.
 - `Message`: log content.
 - `Fields`: optional structured metadata as raw JSON.
 - `RawSize`: original byte size, used by the entry-size cap.

doc/sinks.md

@@ -54,10 +54,10 @@ Payloads are written as the formatter made them, one record per line.
   characters, such as the joiners emoji and Indic scripts need, are kept.
   `never` keeps an application's own ANSI colours; under `auto`, pipes and
   files get the bytes unchanged.
-- Color: the first whole word in a line, in any case, that names the entry's
+- Color: the first word in a line naming the entry's level, by the names the
-  level is painted: `DEBUG`/`DBG` cyan (blue is hard to read on black),
+  [sources](sources.md#file) read, is painted: `DEBUG` cyan (blue is hard to
-  `INFO`/`INF` green, `WARNING`/`WARN` yellow, `ERROR`/`ERR`/`FATAL` bold red,
+  read on black), `INFO` green, `WARN` yellow, `ERROR` bold red, `TRACE`
-  `TRACE` grey. The colors are ANSI 16, so the terminal's theme picks the
+  grey. The colors are ANSI 16, so the terminal's theme picks the
   shades and a Linux or BSD text console renders them; the codes are the
   sink's own, written after escaping. A line whose source found no level
   stays plain. The codes go into whatever the format makes, JSON included:
@@ -216,7 +216,9 @@ Options, each as type and default:
     to: `/` is refused like any other path;
   - an endpoint at `/` keeps the root, and the viewer stays at `/auth/view`.
   The viewer starts with the `replay_lines` backlog, holds one stream against
-  `max_connections`, and says so when all are taken (`server full`).
+  `max_connections`, and says so when all are taken (`server full`). Its
+  search keeps the lines containing a text, in any case, and its level list
+  the entries at or above a level, read as the sources read it.
 - 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/sources.md

@@ -68,8 +68,11 @@ Options, each as type and default:
 - A line is parsed as JSON only when it is an object whose top-level keys are
   all drawn from `time`, `level`, `msg` and `fields` — the four an entry can
   carry. `time` is read as RFC3339Nano. Any other key, and any non-object line,
-  is kept whole as text with the level inferred from common markers
+  is kept whole as text, because parsing it would drop the rest.
-  (`[ERROR]`, `WARN:`, and so on), because parsing it would drop the rest.
+- A text line's level is its first whole word, in any case, naming one:
+  `TRACE`; `DEBUG`, `DBG`; `INFO`, `INF`; `WARN`, `WARNING`; `ERROR`, `ERR`,
+  `FATAL`. `warning: disk full` is WARN, `INFO retry after error` INFO. The
+  console sink paints that word and the http sink's viewer filters on it.
 - `raw = true` skips the JSON branch entirely. The line, plus its newline,
   becomes the message; `fields` stays empty, the time is the read time, and the
   level is inferred from the text as for any unparsed line. Paired with

doc/todo.md

@@ -65,11 +65,7 @@ identity, and both skeletons download the tagged source.
 
 Smaller items found along the way, each independent of the others.
 
-1. Level detection. `source.ExtractLogLevel` needs a delimiter after the name
+1. Command line:
-   (`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.
-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");
@@ -79,9 +75,9 @@ 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.
-3. TLS: the generated-certificate key is one per process, so a pin taken from a
+2. 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`.
-4. `core.ShutdownTimeout` is unused.
+3. `core.ShutdownTimeout` is unused.

internal/core/flow.go

@@ -2,6 +2,7 @@ package core
 
 import (
 	"encoding/json"
+	"strings"
 	"time"
 )
 
@@ -24,3 +25,41 @@ type TransportEvent struct {
 	// Structured entry for re-serializing sinks (chain links). Zero Time => absent
 	Entry LogEntry
 }
+
+// Levels are the entry levels by rising severity, each with the words naming
+// it in a line: the sources, the console sink's painter and the viewer share them
+var Levels = []struct {
+	Level string   `json:"level"`
+	Names []string `json:"names"`
+}{
+	{"TRACE", []string{"TRACE"}},
+	{"DEBUG", []string{"DEBUG", "DBG"}},
+	{"INFO", []string{"INFO", "INF"}},
+	{"WARN", []string{"WARN", "WARNING"}},
+	{"ERROR", []string{"ERROR", "ERR", "FATAL"}},
+}
+
+// LevelWord finds the first whole word of text, in any case, that names a
+// level, or names want when it is set; it returns the level and the word's
+// bounds, and "" when no word does.
+func LevelWord[T string | []byte](text T, want string) (level string, start, end int) {
+	for i := 0; i < len(text); i = end {
+		for i < len(text) && !wordByte(text[i]) {
+			i++
+		}
+		for end = i; end < len(text) && wordByte(text[end]); end++ {
+		}
+		for _, l := range Levels {
+			for _, name := range l.Names {
+				if end-i == len(name) && (want == "" || want == l.Level) && strings.EqualFold(string(text[i:end]), name) {
+					return l.Level, i, end
+				}
+			}
+		}
+	}
+	return "", 0, 0
+}
+
+func wordByte(c byte) bool {
+	return c >= 'a' && c <= 'z' || c >= 'A' && c <= 'Z' || c >= '0' && c <= '9' || c == '_'
+}

internal/core/flow_test.go

@@ -0,0 +1,24 @@
+package core
+
+import "testing"
+
+// A line's level is its first whole word, in any case, naming a level, not the
+// most severe one named; a wanted level skips the names of the others.
+func TestLevelIsTheFirstWordNamingOne(t *testing.T) {
+	for _, c := range []struct {
+		text, want, level string
+		start, end        int
+	}{
+		{"warning disk full", "", "WARN", 0, 7},
+		{"DBG x", "", "DEBUG", 0, 3},
+		{"2026-10-05 [Info] retry after error", "", "INFO", 12, 16},
+		{`{"level":"fatal","msg":"x"}`, "", "ERROR", 10, 15},
+		{"terror informal x_ERR", "", "", 0, 0},
+		{"INFO then ERR", "ERROR", "ERROR", 10, 13},
+	} {
+		level, start, end := LevelWord(c.text, c.want)
+		if level != c.level || start != c.start || end != c.end {
+			t.Errorf("%q want %q: got %q [%d:%d], want %q [%d:%d]", c.text, c.want, level, start, end, c.level, c.start, c.end)
+		}
+	}
+}

internal/sink/console/console.go

@@ -69,18 +69,14 @@ const (
 	DefaultConsoleColor      = "auto"
 )
 
-// levelColors paints the first of a level's names in an entry, ANSI 16 so
+// levelStyles colors the levels in ANSI 16, so the terminal's theme picks the
-// the terminal's theme picks the shades and a text console renders them.
+// shades and a text console renders them; cyan, not blue, stays readable on black
-// Names run longest first; cyan, not blue, stays readable on black.
+var levelStyles = map[string]inline.Style{
-var levelColors = map[string]struct {
+	"ERROR": inline.FgANSI(color.ANSIRed).Bold(),
-	names []string
+	"WARN":  inline.FgANSI(color.ANSIYellow),
-	style inline.Style
+	"INFO":  inline.FgANSI(color.ANSIGreen),
-}{
+	"DEBUG": inline.FgANSI(color.ANSICyan),
-	"ERROR": {[]string{"ERROR", "FATAL", "ERR"}, inline.FgANSI(color.ANSIRed).Bold()},
+	"TRACE": inline.FgANSI(color.ANSIBrightBlack),
-	"WARN":  {[]string{"WARNING", "WARN"}, inline.FgANSI(color.ANSIYellow)},
-	"INFO":  {[]string{"INFO", "INF"}, inline.FgANSI(color.ANSIGreen)},
-	"DEBUG": {[]string{"DEBUG", "DBG"}, inline.FgANSI(color.ANSICyan)},
-	"TRACE": {[]string{"TRACE"}, inline.FgANSI(color.ANSIBrightBlack)},
 }
 
 // NewConsoleSinkPlugin creates a console sink through plugin factory
@@ -273,42 +269,23 @@ func (cs *ConsoleSink) write(event core.TransportEvent) {
 	cs.lastProcessed.Store(time.Now())
 }
 
-// paintLevel colors the first whole-word, case-insensitive occurrence of a
+// paintLevel colors the first word naming the entry's level, after escaping:
-// name of level, after escaping: the escape sequences are the sink's own.
+// the escape sequences are the sink's own
 func paintLevel(p *inline.Printer, payload []byte, level string) []byte {
-	lc, ok := levelColors[level]
+	level, _, _ = core.LevelWord(level, "")
+	style, ok := levelStyles[level]
 	if !ok {
 		return payload
 	}
-	for _, name := range lc.names {
+	if _, i, j := core.LevelWord(payload, level); i < j {
-		for i := 0; i+len(name) <= len(payload); i++ {
-			j := i + len(name)
-			if !nameAt(payload[i:j], name) || i > 0 && word(payload[i-1]) || j < len(payload) && word(payload[j]) {
-				continue
-			}
 		out := make([]byte, 0, len(payload)+16)
 		out = append(out, payload[:i]...)
-			out = append(out, p.Paint(string(payload[i:j]), lc.style)...)
+		out = append(out, p.Paint(string(payload[i:j]), style)...)
 		return append(out, payload[j:]...)
 	}
-	}
 	return payload
 }
 
-// nameAt compares ASCII letters without case; name is upper case
-func nameAt(b []byte, name string) bool {
-	for k := range len(name) {
-		if c := b[k]; c != name[k] && c != name[k]+'a'-'A' {
-			return false
-		}
-	}
-	return true
-}
-
-func word(c byte) bool {
-	return c >= 'a' && c <= 'z' || c >= 'A' && c <= 'Z' || c >= '0' && c <= '9' || c == '_'
-}
-
 // escapeControls writes what a terminal would act on or reorder (C0 and C1
 // controls but tab, DEL, bidi controls, line separators, invalid UTF-8) as
 // <hex>, keeping the final newline: a log line cannot drive the terminal.

internal/sink/console/console_test.go

@@ -29,8 +29,8 @@ func TestEscapeControlsKeepsOnlyLayout(t *testing.T) {
 	}
 }
 
-// The entry's level is painted where its line first names it as a whole
+// The entry's level, under any of its names, is painted where its line first
-// word, in any case, longest name first; other words and levels stay plain.
+// names it as a whole word, in any case; other words and levels stay plain.
 func TestPaintLevelColorsTheFirstWholeName(t *testing.T) {
 	p := inline.New(io.Discard)
 	p.SetColor(true)
@@ -38,6 +38,7 @@ func TestPaintLevelColorsTheFirstWholeName(t *testing.T) {
 	for _, c := range []struct{ in, level, want string }{
 		{"2026 ERROR boom ERROR\n", "ERROR", "2026 " + red + "ERROR\x1b[0m boom ERROR\n"},
 		{"[warning] disk\n", "WARN", "[" + yellow + "warning\x1b[0m] disk\n"},
+		{"INFO: WARN disk\n", "warning", "INFO: " + yellow + "WARN\x1b[0m disk\n"},
 		{"terror_x ERR:1\n", "ERROR", "terror_x " + red + "ERR\x1b[0m:1\n"},
 		{"INFOS informal\n", "INFO", "INFOS informal\n"},
 		{"ERROR without level\n", "", "ERROR without level\n"},

internal/sink/http/http_test.go

@@ -220,7 +220,7 @@ func proxySink(t *testing.T, proxies []any, overrides map[string]any) *HTTPSink
 
 // Behind a proxy the sink serves the client library and the enabled pages
 // under /auth/, each with its type and the pages' CSP; the viewer learns a
-// custom status path from its meta tag.
+// custom status path and the level table from its meta tags.
 func TestProxyModeServesBrowserFiles(t *testing.T) {
 	h := proxySink(t, []any{"127.0.0.1"}, map[string]any{"login_page": true, "viewer_page": true, "status_path": "/api/status"})
 	if !slices.Contains(h.Capabilities(), core.CapProxyTLS) {
@@ -245,6 +245,9 @@ func TestProxyModeServesBrowserFiles(t *testing.T) {
 		if file == "view" && !bytes.Contains(body, []byte(`content="api/status"`)) {
 			t.Error("the viewer page does not carry the custom status path")
 		}
+		if file == "view" && !bytes.Contains(body, []byte(`"WARNING"`)) {
+			t.Error("the viewer page does not carry the level table")
+		}
 	}
 }
 

internal/sink/http/web.go

@@ -4,6 +4,7 @@ import (
 	"bytes"
 	"context"
 	"embed"
+	"encoding/json"
 	"errors"
 	"html"
 	"net/http"
@@ -13,6 +14,7 @@ import (
 	"github.com/lixenwraith/logwisp/internal/authz"
 	"github.com/lixenwraith/logwisp/internal/chain"
 	"github.com/lixenwraith/logwisp/internal/config"
+	"github.com/lixenwraith/logwisp/internal/core"
 	"github.com/lixenwraith/logwisp/internal/netacl"
 )
 
@@ -49,7 +51,8 @@ var webRoutes = []struct {
 // webHandlers maps each GET path a browser uses to its handler. Without a
 // login (no auth, or mtls: the certificate is the login) the viewer is always
 // served; under scram the pages need proxy mode. The viewer learns the status
-// path and whether it logs in from meta tags, as the CSP allows no inline script.
+// path, whether it logs in and the level table from meta tags, as the CSP
+// allows no inline script.
 func webHandlers(o *config.HTTPSinkOptions, p *authz.Policy) (map[string]http.Handler, error) {
 	open := !p.NeedsLogin()
 	on := map[string]bool{"": open || p.BehindProxy(), "login": o.LoginPage, "view": open || o.ViewerPage}
@@ -68,6 +71,8 @@ func webHandlers(o *config.HTTPSinkOptions, p *authz.Policy) (map[string]http.Ha
 			if open {
 				data = bytes.Replace(data, []byte(`name="logwisp-login" content="scram"`), []byte(`name="logwisp-login" content="none"`), 1)
 			}
+			levels, _ := json.Marshal(core.Levels)
+			data = bytes.Replace(data, []byte(`name="logwisp-levels" content=""`), []byte(`name="logwisp-levels" content="`+html.EscapeString(string(levels))+`"`), 1)
 		}
 		handlers[chain.AuthPath+"/"+r.name] = serveWebFile(data, webTypes[path.Ext(r.file)])
 	}

internal/sink/http/web/style.css

@@ -67,7 +67,8 @@ label {
   color: var(--muted);
 }
 
-input {
+input,
+select {
   font: inherit;
   padding: 0.45rem 0.6rem;
   border: 1px solid var(--line);
@@ -95,6 +96,7 @@ progress {
 
 .viewer header {
   display: flex;
+  flex-wrap: wrap;
   align-items: center;
   gap: 1rem;
   padding: 0.6rem 1rem;

internal/sink/http/web/view.html

@@ -6,6 +6,7 @@
 <title>LogWisp stream</title>
 <meta name="logwisp-status" content="status">
 <meta name="logwisp-login" content="scram">
+<meta name="logwisp-levels" content="">
 <link rel="stylesheet" href="style.css">
 <link rel="icon" href="favicon.svg" type="image/svg+xml">
 <script type="module" src="view.js"></script>
@@ -13,6 +14,8 @@
 <body class="viewer">
 <header>
   <h1>LogWisp</h1>
+  <input id="search" type="search" placeholder="Search" aria-label="Show lines containing">
+  <select id="level" aria-label="Lowest level shown"><option value="">All lines</option></select>
   <span id="state" role="status">connecting…</span>
   <button id="logout" type="button">Sign out</button>
 </header>

internal/sink/http/web/view.js

@@ -13,6 +13,13 @@ const signOut = document.getElementById("logout");
 const form = document.getElementById("login");
 const progress = document.getElementById("progress");
 const status = document.getElementById("status");
+const search = document.getElementById("search");
+const lowest = document.getElementById("level");
+// The server's levels by rising severity, each with the words naming it
+const levels = JSON.parse(meta("levels"));
+const named = new Map(levels.flatMap(({ level, names }) => names.map((name) => [name, level])));
+const rank = new Map(levels.map(({ level }, i) => [level, i]));
+for (const { level } of levels) lowest.add(new Option(`${level} and above`, level));
 
 // A page without a login needs no WebCrypto, so plain http works too
 const unavailable = open ? "" : loginUnavailable();
@@ -27,10 +34,35 @@ if (fresh) history.replaceState(null, "", location.pathname + location.search);
 let stopStream = null;
 let timer = null;
 
-function append(line) {
+// An entry's level is its first word naming one, as the server reads a line
+function levelOf(text) {
+  for (const [word] of text.matchAll(/\w+/g)) {
+    const level = named.get(word.toUpperCase());
+    if (level) return level;
+  }
+  return "";
+}
+
+// A line shows when it contains the search, in any case, and its entry's level
+// reaches the lowest chosen; with none chosen, lines without a level show too
+function shown(row) {
+  const floor = rank.get(lowest.value);
+  if (floor !== undefined && !(rank.get(row.dataset.level) >= floor)) return false;
+  const text = search.value.trim().toLowerCase();
+  return !text || row.textContent.toLowerCase().includes(text);
+}
+
+function refilter() {
+  for (const row of log.children) row.hidden = !shown(row);
+  log.scrollTop = log.scrollHeight;
+}
+
+function append(line, level) {
   const atBottom = log.scrollTop + log.clientHeight >= log.scrollHeight - 4;
   const row = document.createElement("div");
   row.textContent = line;
+  row.dataset.level = level;
+  row.hidden = !shown(row);
   log.append(row);
   while (log.childElementCount > MAX_LINES) log.firstElementChild.remove();
   if (atBottom) log.scrollTop = log.scrollHeight;
@@ -73,7 +105,10 @@ function onEvent(type, data) {
     stopStream();
     retry("server shut down");
   }
-  if (type === "message") data.split("\n").forEach(append);
+  if (type === "message") {
+    const level = levelOf(data);
+    for (const line of data.split("\n")) append(line, level);
+  }
 }
 
 function streamWithCookie(url) {
@@ -129,6 +164,9 @@ function retry(reason) {
   timer = setTimeout(connect, 5000);
 }
 
+search.addEventListener("input", refilter);
+lowest.addEventListener("change", refilter);
+
 form.addEventListener("submit", async (event) => {
   event.preventDefault();
   const fields = new FormData(form);

internal/source/source.go

@@ -1,7 +1,6 @@
 package source
 
 import (
-	"strings"
 	"time"
 
 	"github.com/lixenwraith/logwisp/internal/core"
@@ -36,27 +35,8 @@ type SourceStats struct {
 	Details        map[string]any
 }
 
-// ExtractLogLevel heuristically determines the log level from a line of text
+// ExtractLogLevel returns the level the first word naming one marks, or ""
 func ExtractLogLevel(line string) string {
-	patterns := []struct {
+	level, _, _ := core.LevelWord(line, "")
-		patterns []string
+	return level
-		level    string
-	}{
-		{[]string{"[ERROR]", "ERROR:", " ERROR ", "ERR:", "[ERR]", "FATAL:", "[FATAL]"}, "ERROR"},
-		{[]string{"[WARN]", "WARN:", " WARN ", "WARNING:", "[WARNING]"}, "WARN"},
-		{[]string{"[INFO]", "INFO:", " INFO ", "[INF]", "INF:"}, "INFO"},
-		{[]string{"[DEBUG]", "DEBUG:", " DEBUG ", "[DBG]", "DBG:"}, "DEBUG"},
-		{[]string{"[TRACE]", "TRACE:", " TRACE "}, "TRACE"},
-	}
-
-	upperLine := strings.ToUpper(line)
-	for _, group := range patterns {
-		for _, pattern := range group.patterns {
-			if strings.Contains(upperLine, pattern) {
-				return group.level
-			}
-		}
-	}
-
-	return ""
 }