fix var log

packages/bare-os-booter/index.js

@@ -630,6 +630,7 @@ async function executeKernel(disk, store, swarm, initSource) {
       'BARE_OS_SHELL_NOUNSET',
       'BARE_OS_TELEMETRY_NDJSON',
       'BARE_OS_TELEMETRY_OTEL_JSONL',
+      'BARE_OS_VAR_LOG_DEBUG',
       'BARE_OS_PROC_POLL_MS',
       'BARE_OS_TIMER_EVERY_MS_MONOTONIC',
       'BARE_OS_TRACE_ID',

packages/bare-os-booter/lib/bare-os-var-log.js

@@ -1,11 +1,50 @@
 /**
  * Append-only UTF-8 logs under logical `/var/log/…` (VFS maps to the personal Hyperdrive).
+ *
+ * Until the first successful `mkdir`/`writeFile`, `readdir('/var/log')` may be empty even though
+ * `lstat('/var/log')` looks like a directory — logs live under `/var/log/bare-os/` on the logical
+ * tree and on the personal drive under `/.bare-os/…/var/log/<HOME-seg>/` (see `vfs.js` routing).
+ *
+ * Failures are best-effort silent unless **`BARE_OS_VAR_LOG_DEBUG=1`** (or `true`): then messages
+ * go to **`process.stderr`** and **`ctx.console.error`**. Kernel metrics: `varlog.append.*`,
+ * `varlog.ensure.*` (see `bareOsKernelMetricsSnapshot()`).
  */
 
 import {
   BARE_OS_LIFECYCLE_SCHEMA_VERSION,
   BARE_OS_TELEMETRY_SCHEMA_VERSION
 } from './bare-os-lifecycle-schema.js'
+import { bareOsKernelMetricInc } from './bare-os-kernel-metrics.js'
+
+/**
+ * @param {Record<string, unknown>} ctx
+ * @param {string} msg
+ */
+function varLogDebug(ctx, msg) {
+  try {
+    const env =
+      ctx && ctx.env && typeof ctx.env === 'object'
+        ? /** @type {Record<string, string | undefined>} */ (ctx.env)
+        : /** @type {Record<string, string | undefined>} */ ({})
+    const on =
+      env.BARE_OS_VAR_LOG_DEBUG === '1' ||
+      env.BARE_OS_VAR_LOG_DEBUG === 'true'
+    if (!on) return
+    const line = `[bare-os:var-log] ${msg}`
+    try {
+      globalThis.process?.stderr?.write?.(line + '\n')
+    } catch {
+      /* ignore */
+    }
+    try {
+      ctx?.console?.error?.(line)
+    } catch {
+      /* ignore */
+    }
+  } catch {
+    /* ignore */
+  }
+}
 
 export const BARE_OS_VAR_LOG_DIR = '/var/log/bare-os'
 
@@ -69,18 +108,29 @@ const LOG_KEEP_BYTES = 256 * 1024
 export async function ensureBareOsVarLogTree(ctx) {
   try {
     const vfs = ctx.vfs
-    if (!vfs || typeof vfs.mkdir !== 'function') return
+    if (!vfs || typeof vfs.mkdir !== 'function') {
+      bareOsKernelMetricInc('varlog.ensure.skip_no_vfs_mkdir')
+      varLogDebug(ctx, 'ensureBareOsVarLogTree: no ctx.vfs.mkdir')
+      return
+    }
     await vfs.mkdir(BARE_OS_VAR_LOG_DIR, { recursive: true })
     if (
       typeof vfs.readFile !== 'function' ||
       typeof vfs.writeFile !== 'function'
-    )
+    ) {
+      bareOsKernelMetricInc('varlog.ensure.skip_no_vfs_rw')
+      varLogDebug(ctx, 'ensureBareOsVarLogTree: missing vfs.readFile/writeFile')
       return
+    }
     const existing = await vfs.readFile(README_REL)
     if (existing && ctx.b4a.from(existing).length > 0) return
     await vfs.writeFile(README_REL, ctx.b4a.from(README_TEXT))
-  } catch {
-    /* ignore */
+  } catch (e) {
+    bareOsKernelMetricInc('varlog.ensure.error')
+    varLogDebug(
+      ctx,
+      `ensureBareOsVarLogTree: ${e && e.message ? e.message : String(e)}`
+    )
   }
 }
 
@@ -94,7 +144,14 @@ export async function ensureBareOsVarLogTree(ctx) {
 export async function appendVarLog(ctx, logicalFilePath, kind, line) {
   try {
     const vfs = ctx.vfs
-    if (!vfs || typeof vfs.readFile !== 'function') return
+    if (!vfs || typeof vfs.readFile !== 'function') {
+      bareOsKernelMetricInc('varlog.append.skip_no_vfs_readfile')
+      varLogDebug(
+        ctx,
+        'appendVarLog: no vfs.readFile for ' + String(logicalFilePath)
+      )
+      return
+    }
     const prev = await vfs.readFile(logicalFilePath)
     const ts = new Date().toISOString()
     const chunk = ctx.b4a.from(`[${ts}] [${kind}] ${line}\n`)
@@ -119,8 +176,14 @@ export async function appendVarLog(ctx, logicalFilePath, kind, line) {
       kind,
       line: String(line).slice(0, 4000)
     })
-  } catch {
-    /* ignore */
+  } catch (e) {
+    bareOsKernelMetricInc('varlog.append.error')
+    varLogDebug(
+      ctx,
+      `appendVarLog(${String(logicalFilePath)}): ${
+        e && e.message ? e.message : String(e)
+      }`
+    )
   }
 }
 

packages/bare-os-booter/test.js

@@ -119,6 +119,15 @@ import {
   stopBareInitd,
   getLastBareInitdDagSnapshotJson
 } from './lib/bare-initd.js'
+import {
+  appendVarLog,
+  ensureBareOsVarLogTree,
+  KERNEL_CONSOLE_LOG
+} from './lib/bare-os-var-log.js'
+import {
+  bareOsKernelMetricsReset,
+  bareOsKernelMetricsSnapshot
+} from './lib/bare-os-kernel-metrics.js'
 import { parseUnitDropInText } from './lib/bare-initd-user.js'
 import { bareOsProcessTableSnapshot } from './lib/bare-os-process-table.js'
 import { buildBareOsSyscallsProcJson } from './lib/bare-os-syscalls-proc-json.js'
@@ -2835,6 +2844,40 @@ test('vfs chdir /var/log from home', async (t) => {
   rmSync(dir, { recursive: true, force: true })
 })
 
+test('appendVarLog increments skip metric when vfs.readFile missing', async (t) => {
+  bareOsKernelMetricsReset()
+  await appendVarLog(
+    { b4a, env: {}, vfs: { async writeFile() {} } },
+    KERNEL_CONSOLE_LOG,
+    'x',
+    'line'
+  )
+  const snap = bareOsKernelMetricsSnapshot()
+  t.is(snap['varlog.append.skip_no_vfs_readfile'], 1)
+  bareOsKernelMetricsReset()
+})
+
+test('ensureBareOsVarLogTree + appendVarLog populate personal backing', async (t) => {
+  const dir = testCorestoreDir('varlogpop')
+  const store = new Corestore(dir)
+  const sys = new Hyperdrive(store)
+  const personal = new Hyperdrive(store.namespace('pvlog'))
+  await sys.ready()
+  await personal.ready()
+  const ctx = testCtx(sys, personal)
+  await ensureBareOsVarLogTree(ctx)
+  await appendVarLog(ctx, KERNEL_CONSOLE_LOG, 't', 'hello-var-log')
+  const backing = await personal.get(
+    '/.bare-os/var/log/user/bare-os/kernel-console.log'
+  )
+  t.ok(backing)
+  t.ok(b4a.toString(backing).includes('hello-var-log'))
+  const readme = await personal.get('/.bare-os/var/log/user/bare-os/README')
+  t.ok(readme && b4a.toString(readme).includes('kernel-console'))
+  await store.close()
+  rmSync(dir, { recursive: true, force: true })
+})
+
 test('tokenize handles quotes and ops', async (t) => {
   const tok = tokenize('ls -la | cat > out')
   t.ok(tok.some((x) => x.type === 'op' && x.value === '|'))