Merge pull request 'KAN-65: Prepare macOS 0.1.5 build 5' (#163) from feature/KAN-65-release-0-1-5 into main

Reviewed-on: #163

.github/workflows/macos-release.yml

@@ -17,6 +17,8 @@ permissions:
   contents: read
 
 concurrency:
+  # Partial release files may be replaced until the feed is promoted.
+  # Keep every publisher in this group to prevent overlapping rebuilds.
   group: macos-release
   cancel-in-progress: false
 
@@ -198,7 +200,7 @@ jobs:
         id: package
         run: node native/macos-ci.mjs package
 
-      - name: Publish immutable files and verify public Hetzner downloads
+      - name: Upload release files and promote the verified update feed
         env:
           AWS_ACCESS_KEY_ID: ${{ secrets.S3_ACCESS_KEY_ID }}
           AWS_SECRET_ACCESS_KEY: ${{ secrets.S3_SECRET_ACCESS_KEY }}

native/package.json

@@ -1,6 +1,6 @@
 {
     "name": "kanbangit-native",
-    "version": "0.1.3",
+    "version": "0.1.5",
     "private": true,
     "type": "module",
     "scripts": {
@@ -24,5 +24,5 @@
     "devDependencies": {
         "@tauri-apps/cli": "2.11.4"
     },
-    "releaseNotes": "About KanbanGit and Software updates now show the installed app build number correctly."
+    "releaseNotes": "Install Update in the KanbanGit menu is now enabled when an update is available. The Update badge has been removed from the Dock icon."
 }

native/publish-macos.mjs

@@ -63,6 +63,31 @@ export function storageConfiguration(env = process.env) {
 
 const sha256 = (data) => createHash('sha256').update(data).digest('hex');
 
+export function conditionalEtag(etag) {
+    const value =
+        typeof etag === 'string' && etag.startsWith('"') && etag.endsWith('"')
+            ? etag.slice(1, -1)
+            : etag;
+    if (
+        typeof value !== 'string' ||
+        !/^[a-f\d]{32}(?:-[1-9]\d*)?$/i.test(value)
+    ) {
+        throw new Error(
+            'Cannot atomically replace an object without a valid S3 ETag.',
+        );
+    }
+    // Hetzner returns quoted ETags on GET but compares bare values on conditional PUT.
+    return value;
+}
+
+function requiresExistingObjectCheck(error) {
+    // AWS CLI can crash while formatting Hetzner's empty error Message.
+    // This only permits a readback; content checks and conditional writes still apply.
+    return /\(PreconditionFailed\)|\(412\)|argument of type 'NoneType' is not (?:a container or )?iterable/.test(
+        error.message,
+    );
+}
+
 export async function publishMacos({
     env = process.env,
     directory,
@@ -116,13 +141,21 @@ export async function publishMacos({
         's3api',
     ];
     function s3(operation, args) {
-        return run('aws', [
+        try {
-            ...common,
+            return run('aws', [
-            operation,
+                ...common,
-            '--bucket',
+                operation,
-            storage.bucket,
+                '--bucket',
-            ...args,
+                storage.bucket,
-        ]);
+                ...args,
+            ]);
+        } catch (error) {
+            const keyIndex = args.indexOf('--key');
+            const key = keyIndex >= 0 ? ` ${args[keyIndex + 1]}` : '';
+            throw new Error(`S3 ${operation}${key}: ${error.message}`, {
+                cause: error,
+            });
+        }
     }
     const versioningOutput = s3('get-bucket-versioning', [
         '--output',
@@ -152,12 +185,15 @@ export async function publishMacos({
     const staging = mkdtempSync(join(tmpdir(), 'kanbangit-s3-'));
     const keyPrefix = `${storage.prefix}/${metadata.target}/${metadata.version}`;
     const publicPrefix = `${storage.publicBase}/${keyPrefix}`;
+    const latestPrefix = `${storage.prefix}/${metadata.target}`;
+    const latestKey = `${latestPrefix}/latest.json`;
     async function verifyPublic(name, contents, prefix = publicPrefix) {
         for (let attempt = 1; attempt <= 5; attempt++) {
             let response;
             try {
                 response = await fetchPublic(`${prefix}/${name}`, {
                     redirect: 'error',
+                    cache: 'no-store',
                     signal: AbortSignal.timeout(60000),
                 });
             } catch (error) {
@@ -192,36 +228,86 @@ export async function publishMacos({
             await wait(2000);
         }
     }
-    function putImmutable(name, contents, contentType) {
+    function assertUnpublishedRelease() {
+        const file = join(staging, 'published-latest.json');
+        try {
+            s3('get-object', ['--key', latestKey, file]);
+        } catch (error) {
+            if (/\(NoSuchKey\)/.test(error.message)) {
+                return;
+            }
+            if (requiresExistingObjectCheck(error)) {
+                // A broken CLI error message cannot distinguish missing from denied.
+                // Only an authenticated, explicitly empty listing proves absence.
+                const listing = JSON.parse(
+                    s3('list-objects-v2', [
+                        '--prefix',
+                        latestKey,
+                        '--max-keys',
+                        '1',
+                        '--output',
+                        'json',
+                    ]),
+                );
+                if (
+                    listing?.KeyCount === 0 &&
+                    listing.IsTruncated === false &&
+                    Array.isArray(listing.Contents ?? []) &&
+                    (listing.Contents ?? []).length === 0
+                ) {
+                    return;
+                }
+            }
+            throw error;
+        }
+        const published = JSON.parse(readFileSync(file, 'utf8'));
+        if (compareVersions(metadata.version, published.version) <= 0) {
+            throw new Error(
+                'This version has already been released through the update feed; bump the app version. Published objects were not overwritten.',
+            );
+        }
+    }
+    // The macos-release concurrency group serializes the entire publication.
+    // Never run independent publishers against the same release destination.
+    function putReleaseFile(name, contents, contentType) {
         const file = join(staging, name);
         writeFileSync(file, contents);
-        try {
+        function put(condition) {
             s3('put-object', [
                 '--key',
                 `${keyPrefix}/${name}`,
                 '--body',
                 file,
-                '--if-none-match',
+                ...condition,
-                '*',
                 '--content-type',
                 contentType,
                 '--cache-control',
-                'public, max-age=31536000, immutable',
+                'no-cache, max-age=0, must-revalidate',
                 '--content-md5',
                 createHash('md5').update(contents).digest('base64'),
                 '--metadata',
                 `sha256=${sha256(contents)}`,
             ]);
+        }
+        try {
+            put(['--if-none-match', '*']);
         } catch (error) {
-            if (!/\(PreconditionFailed\)|\(412\)/.test(error.message)) {
+            if (!requiresExistingObjectCheck(error)) {
                 throw error;
             }
             const existing = join(staging, `existing-${name}`);
-            s3('get-object', ['--key', `${keyPrefix}/${name}`, existing]);
+            const response = JSON.parse(
+                s3('get-object', [
+                    '--key',
+                    `${keyPrefix}/${name}`,
+                    '--output',
+                    'json',
+                    existing,
+                ]),
+            );
             if (sha256(readFileSync(existing)) !== sha256(contents)) {
-                throw new Error(
+                assertUnpublishedRelease();
-                    `Published ${name} differs; bump the app version. Existing objects were not overwritten.`,
+                put(['--if-match', conditionalEtag(response.ETag)]);
-                );
             }
         }
     }
@@ -246,7 +332,7 @@ export async function publishMacos({
             ],
         ];
         for (const [name, contents, type] of files) {
-            putImmutable(name, contents, type);
+            putReleaseFile(name, contents, type);
             await verifyPublic(name, contents);
         }
         // Completion metadata is written only after every public artifact matches.
@@ -263,7 +349,7 @@ export async function publishMacos({
                 2,
             ) + '\n',
         );
-        putImmutable('release.json', manifest, 'application/json');
+        putReleaseFile('release.json', manifest, 'application/json');
         await verifyPublic('release.json', manifest);
         const latest = Buffer.from(
             JSON.stringify(
@@ -277,10 +363,8 @@ export async function publishMacos({
                 2,
             ) + '\n',
         );
-        putImmutable('update.json', latest, 'application/json');
+        putReleaseFile('update.json', latest, 'application/json');
         await verifyPublic('update.json', latest);
-        const latestPrefix = `${storage.prefix}/${metadata.target}`;
-        const latestKey = `${latestPrefix}/latest.json`;
         const latestFile = join(staging, 'latest.json');
         writeFileSync(latestFile, latest);
         function publishLatest(condition) {
@@ -301,7 +385,7 @@ export async function publishMacos({
         try {
             publishLatest(['--if-none-match', '*']);
         } catch (error) {
-            if (!/\(PreconditionFailed\)|\(412\)/.test(error.message)) {
+            if (!requiresExistingObjectCheck(error)) {
                 throw error;
             }
             const previousFile = join(staging, 'previous-latest.json');
@@ -330,12 +414,7 @@ export async function publishMacos({
                     );
                 }
             } else {
-                if (!response.ETag) {
+                publishLatest(['--if-match', conditionalEtag(response.ETag)]);
-                    throw new Error(
-                        'Cannot atomically update the feed without its ETag.',
-                    );
-                }
-                publishLatest(['--if-match', response.ETag]);
             }
         }
         await verifyPublic(

native/src-tauri/Cargo.lock

@@ -1770,7 +1770,7 @@ dependencies = [
 
 [[package]]
 name = "kanbangit-native"
-version = "0.1.3"
+version = "0.1.5"
 dependencies = [
  "semver",
  "serde",

native/src-tauri/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "kanbangit-native"
-version = "0.1.3"
+version = "0.1.5"
 description = "KanbanGit native application"
 edition = "2021"
 publish = false

native/src-tauri/src/desktop.rs

@@ -308,7 +308,7 @@ pub fn builder() -> tauri::Builder<tauri::Wry> {
         }));
         let menu = MenuBuilder::new(app)
             .item(
-                &SubmenuBuilder::new(app, en::APP_NAME)
+                &SubmenuBuilder::with_id(app, "app-menu", en::APP_NAME)
                     .about_with_text(
                         en::ABOUT,
                         Some(about_metadata(app.package_info().version.to_string())),

native/src-tauri/src/lib.rs

@@ -20,6 +20,9 @@ pub use desktop::{builder, context};
 #[cfg(target_os = "ios")]
 pub use ios::{builder, context};
 
+#[cfg(all(target_os = "macos", feature = "smoke-test"))]
+pub use updates::refresh_menu as refresh_update_menu_for_smoke_test;
+
 #[cfg_attr(mobile, tauri::mobile_entry_point)]
 pub fn run() {
     builder().run(context()).expect("Could not start KanbanGit");

native/src-tauri/src/locale.rs

@@ -2,7 +2,6 @@ pub mod en {
     pub const ABOUT: &str = "About KanbanGit";
     pub const CHECK_UPDATES: &str = "Check For Updates…";
     pub const INSTALL_UPDATE: &str = "Install Update…";
-    pub const UPDATE_BADGE: &str = "Update";
     pub const UPDATES: &str = "KanbanGit Updates";
     pub const APP_NAME: &str = "KanbanGit";
     pub const SERVER_SETTINGS: &str = "Server settings…";

native/src-tauri/src/updates.rs

@@ -123,19 +123,28 @@ fn trusted_navigation(url: &Url) -> bool {
         && url.username().is_empty()
         && url.password().is_none()
 }
+pub fn refresh_menu(app: &AppHandle, available: bool, busy: bool) {
+    if let Some(menu) = app
+        .menu()
+        .and_then(|menu| menu.get("app-menu"))
+        .and_then(|item| {
+            item.as_submenu()
+                .and_then(|menu| menu.get("install-update"))
+        })
+    {
+        if let Some(item) = menu.as_menuitem() {
+            let _ = item.set_enabled(available && !busy);
+        }
+    }
+}
 pub fn refresh(app: &AppHandle) {
     let (view, available, busy) = {
         let state = app.state::<Mutex<State>>();
         let state = state.lock().unwrap();
         (state.view.clone(), state.update.is_some(), state.busy())
     };
-    if let Some(menu) = app.menu().and_then(|m| m.get("install-update")) {
+    refresh_menu(app, available, busy);
-        if let Some(item) = menu.as_menuitem() {
-            let _ = item.set_enabled(available && !busy);
-        }
-    }
     if let Some(window) = app.get_webview_window("updates") {
-        let _ = window.set_badge_label(available.then(|| crate::locale::en::UPDATE_BADGE.into()));
         if let Ok(json) = serde_json::to_string(&view) {
             let _ = window.eval(format!("window.updateStatus?.({json})"));
         }

native/src-tauri/tauri.conf.json

@@ -1,7 +1,7 @@
 {
     "$schema": "https://schema.tauri.app/config/2",
     "productName": "KanbanGit",
-    "version": "0.1.3",
+    "version": "0.1.5",
     "identifier": "de.kanbangit.desktop",
     "build": {
         "frontendDist": "../ui"
@@ -25,7 +25,7 @@
         ],
         "macOS": {
             "minimumSystemVersion": "14.0",
-            "bundleVersion": "3",
+            "bundleVersion": "5",
             "dmg": {
                 "windowSize": {
                     "width": 660,

native/src-tauri/tests/updater_smoke.rs

@@ -1,3 +1,27 @@
+#[cfg(target_os = "macos")]
+#[tauri::command]
+fn updater_smoke_menu(app: tauri::AppHandle) -> Result<(), String> {
+    let submenu = app.menu().unwrap().get("app-menu").unwrap();
+    let item = submenu.as_submenu().unwrap().get("install-update").unwrap();
+    let item = item.as_menuitem().unwrap();
+    for (available, busy, expected) in [
+        (false, false, false), // No update.
+        (true, false, true),   // Available update, also after a retryable failure.
+        (true, true, false),   // Download or installation in progress.
+        (true, false, true),   // Retry after a failed download.
+        (false, true, false),  // A new check clears the previous update.
+        (false, false, false), // Up to date.
+    ] {
+        kanbangit_native::refresh_update_menu_for_smoke_test(&app, available, busy);
+        if item.is_enabled().map_err(|error| error.to_string())? != expected {
+            return Err(format!(
+                "Native install menu has wrong state: available={available}, busy={busy}"
+            ));
+        }
+    }
+    Ok(())
+}
+
 #[cfg(target_os = "macos")]
 #[tauri::command]
 fn updater_smoke_report(app: tauri::AppHandle, passed: bool, reason: String) {
@@ -36,6 +60,7 @@ fn main() {
                     const $ = id => document.getElementById(id);
                     for (let i = 0; i < 100 && !$('installed').textContent; i++) await new Promise(r => setTimeout(r, 50));
                     if ($('installed').textContent !== window.expectedInstalled) throw new Error('Actual installed version/build failed: ' + $('installed').textContent);
+                    await window.__TAURI_INTERNALS__.invoke('updater_smoke_menu');
                     const state = { phase: 'current', currentVersion: '0.1.2', build: '2', version: null, notes: null, downloaded: 0, total: null, error: null, preferences: { automatic: true, intervalHours: 6 } };
                     window.updateStatus(state);
                     if (!$('installed').textContent.includes('0.1.2 (build 2)') || !$('install').hidden || $('check').disabled) throw new Error('Current version state failed');
@@ -64,7 +89,10 @@ fn main() {
     context.config_mut().identifier = format!("de.kanbangit.smoke.updates.{}", std::process::id());
     let app = kanbangit_native::builder()
         .manage(passed.clone())
-        .invoke_handler(tauri::generate_handler![updater_smoke_report])
+        .invoke_handler(tauri::generate_handler![
+            updater_smoke_report,
+            updater_smoke_menu
+        ])
         .plugin(plugin)
         .build(context)
         .expect("App must start");

native/tests/hetzner-conditional.test.js

@@ -0,0 +1,117 @@
+import assert from 'node:assert/strict';
+import { spawnSync } from 'node:child_process';
+import { randomUUID } from 'node:crypto';
+import { mkdtempSync, readFileSync, rmSync, writeFileSync } from 'node:fs';
+import { tmpdir } from 'node:os';
+import { join } from 'node:path';
+import process from 'node:process';
+import test from 'node:test';
+import { conditionalEtag } from '../publish-macos.mjs';
+
+test(
+    'Hetzner conditional writes accept a bare ETag and reject a stale ETag',
+    {
+        skip: process.env.KANBANGIT_S3_INTEGRATION !== '1',
+    },
+    () => {
+        const bucket = process.env.AWS_BUCKET;
+        assert(bucket, 'Set AWS_BUCKET to a test bucket');
+        const directory = mkdtempSync(join(tmpdir(), 'kanbangit-s3-etag-'));
+        const key = `kanbangit-integration-tests/${randomUUID()}.txt`;
+        const file = join(directory, 'object.txt');
+        const downloaded = join(directory, 'downloaded.txt');
+        const run = (operation, args) => {
+            const result = spawnSync(
+                'aws',
+                [
+                    '--debug',
+                    '--endpoint-url',
+                    process.env.AWS_ENDPOINT,
+                    '--region',
+                    process.env.AWS_DEFAULT_REGION,
+                    '--no-cli-pager',
+                    's3api',
+                    operation,
+                    '--bucket',
+                    bucket,
+                    '--key',
+                    key,
+                    ...args,
+                ],
+                { encoding: 'utf8', timeout: 30000 },
+            );
+            // Never expose debug headers: they contain the signed Authorization header.
+            return {
+                status: result.status,
+                stdout: result.stdout,
+                codes: [
+                    ...(result.stderr || '').matchAll(/<Code>([^<]*)<\/Code>/g),
+                ].map((match) => match[1]),
+            };
+        };
+        let created = false;
+        try {
+            writeFileSync(file, 'first');
+            const initial = run('put-object', [
+                '--body',
+                file,
+                '--if-none-match',
+                '*',
+            ]);
+            assert.equal(initial.status, 0, `Create failed: ${initial.codes}`);
+            created = true;
+            const read = run('get-object', ['--output', 'json', downloaded]);
+            assert.equal(read.status, 0, `Read failed: ${read.codes}`);
+            const etag = JSON.parse(read.stdout).ETag;
+            const quoted = run('put-object', [
+                '--body',
+                file,
+                '--if-match',
+                etag,
+            ]);
+            console.log(
+                `Quoted ETag result: exit ${quoted.status}, S3 ${quoted.codes.join(', ')}`,
+            );
+            const bare = conditionalEtag(etag);
+            writeFileSync(file, 'second');
+            const updated = run('put-object', [
+                '--body',
+                file,
+                '--if-match',
+                bare,
+            ]);
+            assert.equal(
+                updated.status,
+                0,
+                `Bare ETag replacement failed: ${updated.codes}`,
+            );
+            writeFileSync(file, 'stale writer');
+            const stale = run('put-object', [
+                '--body',
+                file,
+                '--if-match',
+                bare,
+            ]);
+            assert.notEqual(stale.status, 0);
+            assert(
+                stale.codes.includes('PreconditionFailed'),
+                `Unexpected stale error: ${stale.codes}`,
+            );
+            assert.equal(run('get-object', [downloaded]).status, 0);
+            assert.equal(readFileSync(downloaded, 'utf8'), 'second');
+        } finally {
+            try {
+                if (created) {
+                    const cleanup = run('delete-object', []);
+                    assert.equal(
+                        cleanup.status,
+                        0,
+                        `Cleanup failed: ${cleanup.codes}`,
+                    );
+                }
+            } finally {
+                rmSync(directory, { recursive: true, force: true });
+            }
+        }
+    },
+);

native/tests/macos-workflow.test.js

@@ -75,7 +75,7 @@ function fixture(t) {
         );
         return { ...result, output: readFileSync(output, 'utf8') };
     };
-    return { run, git, checkout, commit };
+    return { run, git, checkout, remote, commit };
 }
 
 test('release selection succeeds using Git alone without an administrative API token', (t) => {
@@ -111,6 +111,39 @@ test('manual release on main accepts an existing tag without moving it', (t) =>
     });
     assert.equal(result.status, 0, result.stderr);
     assert.equal(f.git(f.checkout, 'rev-parse', 'macos-v1.2.3'), f.commit);
+    assert.doesNotMatch(workflow, /inputs\.mode|RELEASE_MODE|\n {2}resume:/);
+    assert.match(workflow, /--ci --target .* --bundles app,dmg/);
+    assert.match(workflow, /node native\/macos-ci.mjs package/);
+    assert.match(workflow, /node native\/publish-macos.mjs upload/);
+});
+
+test('a moved macOS tag selects the new main commit for a full rebuild', (t) => {
+    const f = fixture(t);
+    f.git(
+        f.remote,
+        '-c',
+        'commit.gpgsign=false',
+        'commit',
+        '--allow-empty',
+        '-m',
+        'Fix failed release',
+    );
+    const rebuilt = f.git(f.remote, 'rev-parse', 'HEAD');
+    f.git(f.remote, 'tag', '--force', 'macos-v1.2.3');
+    f.git(
+        f.checkout,
+        'fetch',
+        '--force',
+        'origin',
+        'refs/tags/macos-v1.2.3:refs/tags/macos-v1.2.3',
+    );
+    const result = f.run();
+    assert.equal(result.status, 0, result.stderr);
+    assert.equal(result.output, `commit=${rebuilt}\ntag=macos-v1.2.3\n`);
+    assert.notEqual(rebuilt, f.commit);
+    assert.match(workflow, /tags:\n\s+- "macos-v\*"/);
+    assert.match(workflow, /^ {2}group: macos-release$/m);
+    assert.match(workflow, /^ {2}cancel-in-progress: false$/m);
 });
 
 test('release DMG packaging disables Finder automation in the Tauri action environment', () => {
@@ -127,6 +160,7 @@ test('release DMG packaging disables Finder automation in the Tauri action envir
 });
 
 for (const [name, overrides] of [
+    ['wrong tag case', { GITHUB_REF: 'refs/tags/macOS-V1.2.3' }],
     ['web release tag', { GITHUB_REF: 'refs/tags/v1.2.3' }],
     ['missing tag', { GITHUB_REF: 'refs/tags/macos-v9.9.9' }],
     [

native/tests/publish-macos.test.js

@@ -1,14 +1,64 @@
 import assert from 'node:assert/strict';
 import { Buffer } from 'node:buffer';
+import { spawnSync } from 'node:child_process';
 import { createHash } from 'node:crypto';
 import { mkdtempSync, readFileSync, rmSync, writeFileSync } from 'node:fs';
 import { tmpdir } from 'node:os';
 import { join } from 'node:path';
+import process from 'node:process';
 import test from 'node:test';
-import { publishMacos, storageConfiguration } from '../publish-macos.mjs';
+import { fileURLToPath } from 'node:url';
+import {
+    conditionalEtag,
+    publishMacos,
+    storageConfiguration,
+} from '../publish-macos.mjs';
 import { signedFixture } from './updater-fixture.mjs';
 
-function fixture(t) {
+test('publisher rejects the removed resume command before accessing storage', () => {
+    const result = spawnSync(
+        process.execPath,
+        [
+            fileURLToPath(new URL('../publish-macos.mjs', import.meta.url)),
+            'resume',
+        ],
+        { encoding: 'utf8' },
+    );
+    assert.equal(result.status, 1);
+    assert.equal(result.stdout, '');
+    assert.match(
+        result.stderr,
+        /Use config or upload; upload requires RELEASE_DIRECTORY/,
+    );
+});
+
+test('conditional writes use bare S3 ETags without weakening the condition', () => {
+    const etag = 'b88312b96169f4b2098a4cc43b0abb6a';
+    for (const value of [etag, `"${etag}"`, `${etag}-2`, `"${etag}-2"`]) {
+        assert.equal(conditionalEtag(value), value.replaceAll('"', ''));
+    }
+    for (const invalid of [
+        undefined,
+        null,
+        '',
+        '*',
+        '"*"',
+        `W/"${etag}"`,
+        `"${etag}`,
+        `${etag}"`,
+        `${etag},${etag}`,
+        `${etag}\r\n`,
+        {},
+        42,
+    ]) {
+        assert.throws(() => conditionalEtag(invalid), /valid S3 ETag/);
+    }
+});
+
+function fixture(
+    t,
+    conflictMessage = 'aws failed: (PreconditionFailed) object exists',
+) {
     const directory = mkdtempSync(join(tmpdir(), 'kanbangit-upload-test-'));
     t.after(() => rmSync(directory, { recursive: true, force: true }));
     const metadata = {
@@ -49,7 +99,7 @@ function fixture(t) {
         const operation = args[args.indexOf('s3api') + 1];
         const value = (name) => args[args.indexOf(name) + 1];
         const key = value('--key');
-        events.push({ operation, key });
+        events.push({ operation, key, args });
         if (operation === 'get-bucket-versioning') {
             assert.equal(value('--output'), 'json');
             return '';
@@ -60,18 +110,24 @@ function fixture(t) {
             }
             if (objects.has(key)) {
                 if (!args.includes('--if-match')) {
-                    throw new Error(
+                    throw new Error(conflictMessage);
-                        'aws failed: (PreconditionFailed) object exists',
-                    );
                 }
-                assert.equal(value('--if-match'), '"previous-etag"');
+                assert.equal(
+                    value('--if-match'),
+                    'b88312b96169f4b2098a4cc43b0abb6a',
+                );
             }
             objects.set(key, readFileSync(value('--body')));
             return '{}';
         }
         if (operation === 'get-object') {
+            if (!objects.has(key)) {
+                throw new Error('aws failed: (NoSuchKey) object missing');
+            }
             writeFileSync(args.at(-1), objects.get(key));
-            return JSON.stringify({ ETag: '"previous-etag"' });
+            return JSON.stringify({
+                ETag: '"b88312b96169f4b2098a4cc43b0abb6a"',
+            });
         }
         throw new Error(`Unexpected S3 operation: ${operation}`);
     };
@@ -103,7 +159,7 @@ function fixture(t) {
     };
 }
 
-test('uploads immutable files and writes completion record after public verification', async (t) => {
+test('uploads revalidated files and writes completion record after public verification', async (t) => {
     const f = fixture(t);
     const url = await publishMacos(f);
     assert.equal(
@@ -115,6 +171,14 @@ test('uploads immutable files and writes completion record after public verifica
         8,
     );
     assert.equal(f.objects.size, 8);
+    for (const event of f.events.filter(
+        (event) => event.operation === 'put-object',
+    )) {
+        assert.equal(
+            event.args[event.args.indexOf('--cache-control') + 1],
+            'no-cache, max-age=0, must-revalidate',
+        );
+    }
     assert(f.events.at(-1).key.endsWith('/latest.json'));
     assert.equal(
         f.events.at(-1).key,
@@ -177,14 +241,20 @@ test('retry accepts byte-identical objects without replacing them', async (t) =>
     );
 });
 
-test('different existing release is never overwritten', async (t) => {
+for (const published of ['1.2.3', '1.2.4']) {
-    const f = fixture(t);
+    test(`published release stays protected when the feed is at ${published}`, async (t) => {
-    const key = `releases/macos/${f.metadata.target}/1.2.3/${f.metadata.filename}`;
+        const f = fixture(t);
-    f.objects.set(key, Buffer.from('previous version content'));
+        const key = `releases/macos/${f.metadata.target}/1.2.3/${f.metadata.filename}`;
-    await assert.rejects(publishMacos(f), /bump the app version/);
+        f.objects.set(key, Buffer.from('previous version content'));
-    assert.equal(f.objects.get(key).toString(), 'previous version content');
+        f.objects.set(
-    assert.equal(f.objects.size, 1);
+            `releases/macos/${f.metadata.target}/latest.json`,
-});
+            Buffer.from(JSON.stringify({ version: published })),
+        );
+        await assert.rejects(publishMacos(f), /bump the app version/);
+        assert.equal(f.objects.get(key).toString(), 'previous version content');
+        assert.equal(f.objects.size, 2);
+    });
+}
 
 test('checksum mismatch aborts before contacting S3', async (t) => {
     const f = fixture(t);
@@ -239,7 +309,7 @@ for (const failure of ['private', 'wrong-content', 'network']) {
     });
 }
 
-test('a partial upload can resume with the same files', async (t) => {
+test('a partial upload can be retried with the same files', async (t) => {
     const f = fixture(t);
     const run = f.run;
     f.run = (command, args) => {
@@ -258,6 +328,203 @@ test('a partial upload can resume with the same files', async (t) => {
     assert.equal(f.objects.size, 8);
 });
 
+function rebuild(f) {
+    const updater = Buffer.from('rebuilt signed update');
+    const signing = signedFixture(updater);
+    f.publicKey = signing.publicKey;
+    f.metadata.notes = 'Fixed build of the same version';
+    for (const [name, contents] of [
+        [f.metadata.filename, Buffer.from('rebuilt disk image')],
+        [f.metadata.updaterFilename, updater],
+    ]) {
+        writeFileSync(join(f.directory, name), contents);
+        writeFileSync(
+            join(f.directory, `${name}.sha256`),
+            `${createHash('sha256').update(contents).digest('hex')}  ${name}\n`,
+        );
+    }
+    writeFileSync(
+        join(f.directory, `${f.metadata.updaterFilename}.sig`),
+        signing.signature,
+    );
+}
+
+for (const previous of [null, '1.0.0']) {
+    for (const interruptedFile of ['.sha256', '/latest.json']) {
+        test(`rebuild replaces unfinished ${interruptedFile} release with previous feed ${previous}`, async (t) => {
+            const f = fixture(t);
+            const latestKey = `releases/macos/${f.metadata.target}/latest.json`;
+            const previousBytes =
+                previous === null
+                    ? undefined
+                    : Buffer.from(JSON.stringify({ version: previous }));
+            if (previousBytes) {
+                f.objects.set(latestKey, previousBytes);
+            }
+            const run = f.run;
+            f.run = (command, args) => {
+                if (
+                    args.includes('put-object') &&
+                    args[args.indexOf('--key') + 1].endsWith(interruptedFile)
+                ) {
+                    throw new Error('upload interrupted');
+                }
+                return run(command, args);
+            };
+            await assert.rejects(publishMacos(f), /upload interrupted/);
+            assert.deepEqual(f.objects.get(latestKey), previousBytes);
+            rebuild(f);
+            f.events.length = 0;
+            let promoted = false;
+            f.run = (command, args) => {
+                if (!promoted) {
+                    assert.deepEqual(f.objects.get(latestKey), previousBytes);
+                }
+                const result = run(command, args);
+                if (args.includes('put-object') && args.includes(latestKey)) {
+                    promoted = true;
+                }
+                return result;
+            };
+            await publishMacos(f);
+            assert.equal(f.objects.size, 8);
+            assert.equal(JSON.parse(f.objects.get(latestKey)).version, '1.2.3');
+            assert.equal(
+                JSON.parse(f.objects.get(latestKey)).notes,
+                f.metadata.notes,
+            );
+            for (const name of [
+                f.metadata.filename,
+                `${f.metadata.filename}.sha256`,
+                f.metadata.updaterFilename,
+                `${f.metadata.updaterFilename}.sig`,
+                `${f.metadata.updaterFilename}.sha256`,
+            ]) {
+                assert.deepEqual(
+                    f.objects.get(
+                        `releases/macos/${f.metadata.target}/1.2.3/${name}`,
+                    ),
+                    readFileSync(join(f.directory, name)),
+                );
+            }
+            const published = [...f.objects.entries()];
+            rebuild(f);
+            await assert.rejects(publishMacos(f), /already been released/);
+            assert.deepEqual([...f.objects.entries()], published);
+        });
+    }
+}
+
+test('failure after promoting the feed still protects that version from rebuilding', async (t) => {
+    const f = fixture(t);
+    const fetchPublic = f.fetchPublic;
+    f.fetchPublic = async (url, options) =>
+        url.endsWith('/latest.json')
+            ? { ok: false, status: 403 }
+            : fetchPublic(url, options);
+    await assert.rejects(publishMacos(f), /HTTP 403/);
+    const published = [...f.objects.entries()];
+    rebuild(f);
+    await assert.rejects(publishMacos(f), /already been released/);
+    assert.deepEqual([...f.objects.entries()], published);
+});
+
+test('a concurrent change to a partial artifact is not overwritten', async (t) => {
+    const f = fixture(t);
+    const key = `releases/macos/${f.metadata.target}/1.2.3/${f.metadata.filename}`;
+    f.objects.set(key, Buffer.from('unfinished old build'));
+    const run = f.run;
+    f.run = (command, args) => {
+        if (args.includes('--if-match')) {
+            assert(args.includes(key));
+            f.objects.set(key, Buffer.from('concurrent winner'));
+            throw new Error('(PreconditionFailed) concurrent replacement');
+        }
+        return run(command, args);
+    };
+    await assert.rejects(publishMacos(f), /concurrent replacement/);
+    assert.equal(f.objects.get(key).toString(), 'concurrent winner');
+    assert.equal(f.objects.size, 1);
+});
+
+for (const failure of [
+    'AccessDenied',
+    'network failure',
+    'invalid JSON',
+    'invalid version',
+]) {
+    test(`cannot replace a partial artifact when the feed check has ${failure}`, async (t) => {
+        const f = fixture(t);
+        const key = `releases/macos/${f.metadata.target}/1.2.3/${f.metadata.filename}`;
+        const latestKey = `releases/macos/${f.metadata.target}/latest.json`;
+        f.objects.set(key, Buffer.from('unfinished old build'));
+        f.objects.set(
+            latestKey,
+            Buffer.from(
+                failure === 'invalid version' ? '{"version":"invalid"}' : '{',
+            ),
+        );
+        const originals = [...f.objects.entries()];
+        const run = f.run;
+        f.run = (command, args) => {
+            if (
+                args.includes('get-object') &&
+                args.includes(latestKey) &&
+                !failure.startsWith('invalid')
+            ) {
+                throw new Error(failure);
+            }
+            return run(command, args);
+        };
+        await assert.rejects(publishMacos(f));
+        assert.deepEqual([...f.objects.entries()], originals);
+    });
+}
+
+for (const listing of [
+    { KeyCount: 0, IsTruncated: false },
+    { KeyCount: 1, IsTruncated: false, Contents: [{ Key: 'latest.json' }] },
+    {},
+    { KeyCount: 0, IsTruncated: true },
+    { KeyCount: 0, IsTruncated: false, Contents: '' },
+    'AccessDenied',
+]) {
+    test(`ambiguous feed read error needs a proven empty listing: ${JSON.stringify(listing)}`, async (t) => {
+        const f = fixture(t);
+        const key = `releases/macos/${f.metadata.target}/1.2.3/${f.metadata.filename}`;
+        const latestKey = `releases/macos/${f.metadata.target}/latest.json`;
+        f.objects.set(key, Buffer.from('unfinished old build'));
+        const run = f.run;
+        f.run = (command, args) => {
+            if (args.includes('get-object') && args.includes(latestKey)) {
+                throw new Error(
+                    "argument of type 'NoneType' is not a container or iterable",
+                );
+            }
+            if (args.includes('list-objects-v2')) {
+                assert.equal(args[args.indexOf('--prefix') + 1], latestKey);
+                if (listing === 'AccessDenied') {
+                    throw new Error('AccessDenied');
+                }
+                return JSON.stringify(listing);
+            }
+            return run(command, args);
+        };
+        if (
+            listing.KeyCount === 0 &&
+            listing.IsTruncated === false &&
+            !('Contents' in listing)
+        ) {
+            await publishMacos(f);
+            assert.equal(f.objects.size, 8);
+        } else {
+            await assert.rejects(publishMacos(f), /NoneType|AccessDenied/);
+            assert.equal(f.objects.get(key).toString(), 'unfinished old build');
+            assert.equal(f.objects.size, 1);
+        }
+    });
+}
+
 for (const status of [403, 404, 408, 429, 500, 502, 503, 504, 'network']) {
     test(`temporary public download failure ${status} recovers before completion`, async (t) => {
         const f = fixture(t);
@@ -378,13 +645,13 @@ test('rejects a corrupt updater archive before publishing any object', async (t)
     assert.equal(f.objects.size, 0);
 });
 
-test('atomically promotes a newer feed only after all immutable objects are public', async (t) => {
+test('atomically promotes a newer feed only after all release files are public', async (t) => {
     const f = fixture(t);
     const latestKey = `releases/macos/${f.metadata.target}/latest.json`;
     f.objects.set(latestKey, Buffer.from(JSON.stringify({ version: '1.0.0' })));
     await publishMacos(f);
     assert.equal(JSON.parse(f.objects.get(latestKey)).version, '1.2.3');
-    const immutableVerified = f.events.findIndex(
+    const releaseVerified = f.events.findIndex(
         (event) =>
             event.operation === 'public-get' &&
             event.key.endsWith('/update.json'),
@@ -392,7 +659,7 @@ test('atomically promotes a newer feed only after all immutable objects are publ
     const latestPut = f.events.findIndex(
         (event) => event.operation === 'put-object' && event.key === latestKey,
     );
-    assert(latestPut > immutableVerified);
+    assert(latestPut > releaseVerified);
 });
 
 for (const previous of [
@@ -427,3 +694,90 @@ test('concurrent feed replacement fails without overwriting the winner', async (
     await assert.rejects(publishMacos(f), /concurrent publication/);
     assert.equal(JSON.parse(f.objects.get(key)).version, '2.0.0');
 });
+
+for (const message of [
+    "aws failed (exit 255). aws: [ERROR]: argument of type 'NoneType' is not a container or iterable",
+    "aws failed (exit 255). argument of type 'NoneType' is not iterable",
+]) {
+    test(`empty S3 error message permits verified promotion and identical retry: ${message}`, async (t) => {
+        const f = fixture(t, message);
+        const key = `releases/macos/${f.metadata.target}/latest.json`;
+        f.objects.set(key, Buffer.from(JSON.stringify({ version: '1.0.0' })));
+        await publishMacos(f);
+        assert.equal(JSON.parse(f.objects.get(key)).version, '1.2.3');
+        const published = [...f.objects.entries()];
+        await publishMacos(f);
+        assert.deepEqual([...f.objects.entries()], published);
+    });
+
+    test(`empty S3 error cannot replace a published release: ${message}`, async (t) => {
+        const f = fixture(t, message);
+        const key = `releases/macos/${f.metadata.target}/1.2.3/${f.metadata.filename}`;
+        f.objects.set(key, Buffer.from('different existing release'));
+        f.objects.set(
+            `releases/macos/${f.metadata.target}/latest.json`,
+            Buffer.from(JSON.stringify({ version: '1.2.3' })),
+        );
+        await assert.rejects(publishMacos(f), /bump the app version/);
+        assert.equal(f.objects.size, 2);
+        assert.equal(
+            f.objects.get(key).toString(),
+            'different existing release',
+        );
+    });
+
+    for (const previous of [
+        { version: '2.0.0' },
+        { version: '1.2.3', notes: 'different' },
+    ]) {
+        test(`empty S3 error cannot bypass feed conflict checks ${previous.version}: ${message}`, async (t) => {
+            const f = fixture(t, message);
+            const key = `releases/macos/${f.metadata.target}/latest.json`;
+            const original = Buffer.from(JSON.stringify(previous));
+            f.objects.set(key, original);
+            await assert.rejects(publishMacos(f), /downgrade|differs/);
+            assert.deepEqual(f.objects.get(key), original);
+        });
+    }
+
+    test(`empty S3 error aborts when existing contents cannot be read: ${message}`, async (t) => {
+        const f = fixture(t, message);
+        const run = f.run;
+        f.run = (command, args) => {
+            if (args.includes('put-object')) {
+                throw new Error(message);
+            }
+            if (args.includes('get-object')) {
+                throw new Error('AccessDenied');
+            }
+            return run(command, args);
+        };
+        await assert.rejects(publishMacos(f), /S3 get-object .*AccessDenied/);
+        assert.equal(f.objects.size, 0);
+    });
+
+    test(`empty S3 error during conditional replacement preserves a concurrent winner: ${message}`, async (t) => {
+        const f = fixture(t, message);
+        const key = `releases/macos/${f.metadata.target}/latest.json`;
+        f.objects.set(key, Buffer.from(JSON.stringify({ version: '1.0.0' })));
+        const run = f.run;
+        let attempts = 0;
+        f.run = (command, args) => {
+            if (args.includes('--if-match')) {
+                attempts++;
+                f.objects.set(
+                    key,
+                    Buffer.from(JSON.stringify({ version: '2.0.0' })),
+                );
+                throw new Error(message);
+            }
+            return run(command, args);
+        };
+        await assert.rejects(
+            publishMacos(f),
+            /S3 put-object .*latest.json: .*NoneType/,
+        );
+        assert.equal(attempts, 1);
+        assert.equal(JSON.parse(f.objects.get(key)).version, '2.0.0');
+    });
+}