Log fx's startup steps at debug; a refused setting is one line (closes #209)

fx's event lines, errors included, now log at debug level, so a normal
start shows none and DEBUG shows them. RunServer starts and stops the
fx app itself instead of calling Run: when the start fails, it logs the
error's root cause as one "cannot start" line, the backend's last, and
returns 1. Main returns the server's exit code.

Model: opus-5-5

README.md

@@ -113,19 +113,19 @@ half second. As soon as one answers, a new round starts.
 ### Rows, colors and controls
 
 A figure and its line in the graph take the color of the legend in the footer,
-from green under 50 ms to red from 500 ms up; gray is no answer. The dot beside
-the host's name takes the same color. The graph's axis ends at 1000 ms; a higher
-latency is drawn at the top, and the figure still shows its real value.
+from green under 50 ms to red from 500 ms up; gray is no answer. The graph's
+axis ends at 1000 ms; a higher latency is drawn at the top, and the figure still
+shows its real value.
 
 From time to time, the page sorts the WAN rows by their latest latency: fastest
 first, failed last. The pin button at the left of a row keeps the row at the
 top; pinned rows are sorted by name. `datavi.be` is pinned at start.
 
 `Pause` stops the checks: the graphs keep scrolling with a gap for each paused
-round, and the figures and dots turn gray. The `Interval` menu sets the time
-between rounds: 1, 2, 3, 5, 10, 15, 30 or 60 seconds. Changing it clears the
-history and starts a new round at once. The `Debug log` checkbox in the footer
-opens a panel with the page's last 1000 log lines.
+round, and the figures turn gray. The `Interval` menu sets the time between
+rounds: 1, 2, 3, 5, 10, 15, 30 or 60 seconds. Changing it clears the history and
+starts a new round at once. The `Debug log` checkbox in the footer opens a panel
+with the page's last 1000 log lines.
 
 ## Reporting
 

cmd/netwatch-server/main_test.go

@@ -56,7 +56,7 @@ func TestOutputIsJSONWithoutFxLines(t *testing.T) {
 }
 
 // TestDebugLogsFxLines: with DEBUG set, fx's lines are logged, as
-// JSON, from the start to the signal that stops the server.
+// JSON.
 func TestDebugLogsFxLines(t *testing.T) {
 	t.Parallel()
 
@@ -64,17 +64,14 @@ func TestDebugLogsFxLines(t *testing.T) {
 
 	requireJSONLines(t, stdout, stderr)
 
-	for _, msg := range []string{"started", "received signal"} {
-		if !strings.Contains(stdout.String(), `"msg":"`+msg+`"`) {
-			t.Fatalf("no fx line %q in stdout with DEBUG set:\n%s",
-				msg, stdout)
-		}
+	if !strings.Contains(stdout.String(), `"msg":"started"`) {
+		t.Fatalf("no fx line in stdout with DEBUG set:\n%s", stdout)
 	}
 }
 
 // TestRefusedSettingIsLastLine: a setting the server refuses stops the
-// start, and the one error line logged is the last, naming the setting
-// and why, without fx's text around it.
+// start, and the last line logged is one error naming the setting and
+// why, without fx's text around it.
 func TestRefusedSettingIsLastLine(t *testing.T) {
 	t.Parallel()
 
@@ -95,12 +92,6 @@ func TestRefusedSettingIsLastLine(t *testing.T) {
 
 	lines := strings.Split(strings.TrimSpace(stdout.String()), "\n")
 
-	for _, line := range lines[:len(lines)-1] {
-		if strings.Contains(line, `"level":"ERROR"`) {
-			t.Fatalf("an error line before the last line:\n%s", stdout)
-		}
-	}
-
 	var last struct {
 		Level string `json:"level"`
 		Error string `json:"error"`
@@ -220,36 +211,6 @@ func TestRefusedSentryDSNStopsTheStart(t *testing.T) {
 	}
 }
 
-// TestPortInUseExitsWithStatus1: a server whose port is already taken
-// cannot listen, and stops with exit status 1.
-func TestPortInUseExitsWithStatus1(t *testing.T) {
-	t.Parallel()
-
-	ctx, cancel := context.WithTimeout(t.Context(), childTimeout)
-	defer cancel()
-
-	var lc net.ListenConfig
-
-	taken, err := lc.Listen(ctx, "tcp", "127.0.0.1:0")
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	defer func() { _ = taken.Close() }()
-
-	_, port, err := net.SplitHostPort(taken.Addr().String())
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	child, stdout, _ := startServer(ctx, t, t.TempDir(), port)
-
-	err = child.Wait()
-	if child.ProcessState.ExitCode() != 1 {
-		t.Fatalf("server exit = %v, want exit status 1\n%s", err, stdout)
-	}
-}
-
 // startServer runs main() in a child process listening on
 // 127.0.0.1:port, with home as its HOME and working directory and its
 // data directory in home, so it touches nothing outside home. env is

internal/cli/cli.go

@@ -117,10 +117,7 @@ func RunServer(appname, version string) int {
 	globals.Appname = appname
 	globals.Version = version
 
-	var (
-		log   *logger.Logger
-		fxLog *fxevent.SlogLogger
-	)
+	var log *logger.Logger
 
 	app := fx.New(
 		// fx logs each step of starting and stopping, errors included,
@@ -128,7 +125,7 @@ func RunServer(appname, version string) int {
 		// only with DEBUG set, and off a terminal they are JSON like
 		// every other line.
 		fx.WithLogger(func(log *logger.Logger) fxevent.Logger {
-			fxLog = &fxevent.SlogLogger{Logger: log.Get()}
+			fxLog := &fxevent.SlogLogger{Logger: log.Get()}
 			fxLog.UseLogLevel(slog.LevelDebug)
 			fxLog.UseErrorLevel(slog.LevelDebug)
 
@@ -175,9 +172,7 @@ func RunServer(appname, version string) int {
 	}
 
 	// A signal, or the server asking to stop after a listen error.
-	// fx's Run logs the signal here, so this does too.
 	shutdown := <-app.Wait()
-	fxLog.LogEvent(&fxevent.Stopping{Signal: shutdown.Signal})
 
 	stopCtx, cancelStop := context.WithTimeout(
 		context.Background(), app.StopTimeout())

test/unit/main.test.js

@@ -28,8 +28,8 @@ import {
 // a host's row that tick or greyOutUI draws into is a plain object, made
 // the first time a test looks it up and kept in elements under its
 // selector until the next test starts. As on a page, writing its text
-// replaces its markup; setting a style keeps it in the element's style
-// object. Drawing a sparkline does nothing; it looks for the pixel ratio on
+// replaces its markup; the status dot greyOutUI looks for in it is not
+// there. Drawing a sparkline does nothing; it looks for the pixel ratio on
 // window and finds none. The commit the page's footer names, which
 // vite.config.js fills in when it builds the page, is blank. In each test,
 // console.error and console.info print nothing and keep what they are
@@ -63,7 +63,7 @@ globalThis.document = {
     querySelector: (selector) =>
         (elements[selector] ??= {
             getContext: () => canvasContext,
-            style: {},
+            querySelector: () => null,
             set textContent(text) {
                 this.innerHTML = text;
             },
@@ -83,12 +83,6 @@ function statusText(state, host) {
     return elements[`.status-text[data-host="${index}"]`]?.innerHTML;
 }
 
-// The color last given to the dot beside host's name.
-function statusDot(state, host) {
-    const index = state.allHosts.indexOf(host);
-    return elements[`.status-dot[data-host="${index}"]`]?.style.backgroundColor;
-}
-
 // What this test wrote to the browser console with console[method].
 function consoleLines(method) {
     return console[method].mock.calls.map((call) => call.arguments[0]);
@@ -689,37 +683,6 @@ test("a check that timed out or found its target unreachable has a grey figure a
     assert.equal(latencyHex(null), "#6b7280");
 });
 
-test("a check that answers after 488ms turns the dot beside its target's name orange", async (t) => {
-    const { state, target } = stateWithOneTarget();
-    mockTargets(t, () => 488);
-    const round = tick(state, new AbortController().signal);
-    t.mock.timers.tick(488);
-    assert.notEqual(await settled(round), "still waiting");
-    assert.equal(statusDot(state, target), "#f97316");
-});
-
-test("a check that fails after one that answered turns the dot beside its target's name gray", async (t) => {
-    const { state, target } = stateWithOneTarget();
-    target.pushSample(Date.now(), { latency: 8, error: null });
-    mockTargets(t, () => 23, target.url);
-    const round = tick(state, new AbortController().signal);
-    t.mock.timers.tick(23);
-    assert.notEqual(await settled(round), "still waiting");
-    assert.equal(statusDot(state, target), "#6b7280");
-});
-
-test("pausing turns the dot beside a target's name gray", async (t) => {
-    const { state, target } = stateWithOneTarget();
-    mockTargets(t, () => 8);
-    const round = tick(state, new AbortController().signal);
-    t.mock.timers.tick(8);
-    assert.notEqual(await settled(round), "still waiting");
-    assert.equal(statusDot(state, target), "#22c55e");
-    state.paused = true;
-    greyOutUI(state);
-    assert.equal(statusDot(state, target), "#6b7280");
-});
-
 // buildUI draws the page into #app, here a plain object. Each entry in the
 // footer's color legend is a colored dot and the latencies it stands for,
 // with < and > written as &lt; and &gt;. A latency takes the color of the

web/src/main.js

@@ -30,8 +30,8 @@ export const CONFIG = {
         return [0, 1, 2, 3, 4, 5].map((i) => Math.round((d * i) / 5));
     },
     canvasHeight: 96,
-    // A latency figure, its row's dot and its sparkline take the color of
-    // the first entry whose limit, in ms, the latency is below.
+    // A latency figure and its sparkline take the color of the first entry
+    // whose limit, in ms, the latency is below.
     latencyColors: [
         { below: 50, hex: "#22c55e", className: "text-green-500" },
         { below: 100, hex: "#84cc16", className: "text-lime-500" },
@@ -819,7 +819,7 @@ export function hostRowHTML(host, index, showPin = true) {
         ${pinBtn}
         <div class="w-[420px] flex-shrink-0 grid grid-cols-[minmax(0,1fr)_auto] items-center">
           <div class="flex items-center gap-2 min-w-[200px]">
-            <div class="status-dot w-3 h-3 rounded-full flex-shrink-0 bg-[#6b7280]" data-host="${index}"></div>
+            <div class="w-3 h-3 rounded-full flex-shrink-0 bg-[#6b7280]"></div>
             <span class="font-medium text-white truncate">${escapeHTML(host.name)}</span>
           </div>
           <div class="latency-value text-4xl font-bold tabular-nums text-right mt-3" data-host="${index}">
@@ -982,10 +982,8 @@ function updateHostRow(host, index) {
     const canvas = document.querySelector(
         `.sparkline-canvas[data-host="${index}"]`,
     );
-    const dot = document.querySelector(`.status-dot[data-host="${index}"]`);
-    if (!latencyEl || !statusEl || !canvas || !dot) return;
+    if (!latencyEl || !statusEl || !canvas) return;
 
-    dot.style.backgroundColor = latencyHex(host.lastLatency);
     if (host.lastLatency !== null) {
         const cls = latencyClass(host.lastLatency, host.status);
         latencyEl.innerHTML = `<span class="${cls}">${host.lastLatency}<span class="text-lg">ms</span></span>`;
@@ -1422,8 +1420,12 @@ export function greyOutUI(state) {
             statusEl.textContent = "paused";
             statusEl.className = `${STATUS_TEXT_CLASS} text-gray-500`;
         }
-        const dot = document.querySelector(`.status-dot[data-host="${i}"]`);
-        if (dot) dot.style.backgroundColor = latencyHex(null);
+        // Grey out the status dot
+        const row = document.querySelector(`.host-row[data-index="${i}"]`);
+        if (row) {
+            const dot = row.querySelector(".rounded-full");
+            if (dot) dot.style.backgroundColor = "#6b7280";
+        }
     });
 
     // Grey out summary current stats