ci: stop the weekly flake.lock bot from running the whole pipeline (#5539)

nix-flake-update opens a PR every Sunday that changes flake.lock and nothing
else. flake.lock is consumed only by Nix packaging — cargo never reads it — yet
it was in no paths filter, so each of those PRs ran the full Continuous
Integration pipeline and the merge then ran Build and Release too. Added to all
four lists that have to agree: ci.yml's push and pull_request paths-ignore,
build.yml's push paths-ignore, and ci-docs-only.yml's paths.

The cron stays. flake.lock still has consumers — anyone running `nix build` or
`nix develop` — so stopping the updates would remove the workflow's output, not
just its CI cost.

Those four lists drifting is a silent failure, so scripts/check_ci_paths_sync.sh
now asserts the pair that matters: ci.yml's pull_request paths-ignore must equal
ci-docs-only.yml's paths. An entry present only in the first means a PR touching
those files triggers neither workflow, nobody reports "Test and Lint" or "Quick
Checks", and the PR waits on a required check forever. It also asserts both
companion job names still exist, since renaming one produces the same hang. The
push list is not compared: no required check is reported for push events.

Also in this cleanup:

- nix-flake-update's GITHUB_TOKEN drops to contents: read. The branch push and
  the pull request are both made by update-flake-lock with the
  FLAKE_UPDATE_TOKEN PAT, so the write scopes were an unused repo-write
  credential on an unattended weekly job.
- build.yml's build_docker dispatch input is documented as advisory. docker.yml
  triggers on workflow_run and requires the triggering event to be a tag push,
  so a manual dispatch never reaches it whatever this input says.
- The nine disabled workflow files get a banner saying so. Their
  disabled_manually state lives in GitHub's UI and is invisible when reading the
  file, which has already misled one audit into treating dead workflows as live.

Refs: rustfs/backlog#1598, rustfs/backlog#1603

.github/workflows/build.yml

@@ -50,12 +50,18 @@ on:
       - "**/*.svg"
       - ".gitignore"
       - ".dockerignore"
+      - "flake.lock"
   schedule:
     - cron: "0 1 * * 0" # Weekly on Sunday 01:00 UTC (staggered after the ci.yml midnight cron)
   workflow_dispatch:
     inputs:
       build_docker:
-        description: "Build and push Docker images after binary build"
+        # Advisory only. docker.yml triggers on workflow_run and its job-level
+        # condition requires the triggering event to be a tag push, so a manual
+        # dispatch of this workflow never produces images regardless of this
+        # value. Kept because the summary step reports it; wiring it up would
+        # mean teaching docker.yml's version parser a second event shape.
+        description: "Build and push Docker images after binary build (ignored: dispatch runs never reach docker.yml)"
         required: false
         default: true
         type: boolean

.github/workflows/ci-docs-only.yml

@@ -53,6 +53,7 @@ on:
       - ".github/workflows/build.yml"
       - ".github/workflows/docker.yml"
       - ".github/workflows/audit.yml"
+      - "flake.lock"
 
 permissions:
   contents: read
@@ -110,6 +111,8 @@ jobs:
 
       - name: Check no planning docs committed
         run: ./scripts/check_no_planning_docs.sh
+      - name: Check CI paths stay in sync
+        run: ./scripts/check_ci_paths_sync.sh
 
   test-and-lint:
     name: Test and Lint

.github/workflows/ci.yml

@@ -33,6 +33,7 @@ on:
       - ".github/workflows/build.yml"
       - ".github/workflows/docker.yml"
       - ".github/workflows/audit.yml"
+      - "flake.lock"
   pull_request:
     types: [ opened, synchronize, reopened, closed ]
     branches: [ main ]
@@ -54,6 +55,7 @@ on:
       - ".github/workflows/build.yml"
       - ".github/workflows/docker.yml"
       - ".github/workflows/audit.yml"
+      - "flake.lock"
   merge_group:
     types: [ checks_requested ]
   schedule:
@@ -142,6 +144,8 @@ jobs:
 
       - name: Check no planning docs committed
         run: ./scripts/check_no_planning_docs.sh
+      - name: Check CI paths stay in sync
+        run: ./scripts/check_ci_paths_sync.sh
 
   test-and-lint:
     name: Test and Lint

.github/workflows/e2e-s3tests.yml

@@ -45,6 +45,13 @@
 # The PR gate (ci.yml s3-implemented-tests) is unaffected: it avoids Docker
 # via DEPLOY_MODE=binary and defers all pip setup to run.sh's self-bootstrap.
 
+# DISABLED. This workflow is switched off in the repository's Actions settings
+# (state: disabled_manually) and does not run on any trigger, including its cron
+# and workflow_dispatch. That state lives in GitHub's UI and is invisible when
+# reading this file, which has already misled at least one audit — hence this
+# banner. Re-enabling is a UI action; anyone doing so should first check that the
+# workflow still matches the current CI layout. See rustfs/backlog#1603.
+#
 name: e2e-s3tests
 
 on:

.github/workflows/fuzz.yml

@@ -12,6 +12,13 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
+# DISABLED. This workflow is switched off in the repository's Actions settings
+# (state: disabled_manually) and does not run on any trigger, including its cron
+# and workflow_dispatch. That state lives in GitHub's UI and is invisible when
+# reading this file, which has already misled at least one audit — hence this
+# banner. Re-enabling is a UI action; anyone doing so should first check that the
+# workflow still matches the current CI layout. See rustfs/backlog#1603.
+#
 name: Fuzz
 
 on:

.github/workflows/issue-translator.yml

@@ -12,6 +12,13 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
+# DISABLED. This workflow is switched off in the repository's Actions settings
+# (state: disabled_manually) and does not run on any trigger, including its cron
+# and workflow_dispatch. That state lives in GitHub's UI and is invisible when
+# reading this file, which has already misled at least one audit — hence this
+# banner. Re-enabling is a UI action; anyone doing so should first check that the
+# workflow still matches the current CI layout. See rustfs/backlog#1603.
+#
 name: "issue-translator"
 on:
   issue_comment:

.github/workflows/minio-interop.yml

@@ -23,6 +23,13 @@
 # Runner: GitHub-hosted `ubuntu-latest`. It reliably ships Docker + Python,
 # unlike the self-hosted fleet, whose pods drift in Docker/pip availability
 # (see the infra note in e2e-s3tests.yml). Nightly + manual only.
+# DISABLED. This workflow is switched off in the repository's Actions settings
+# (state: disabled_manually) and does not run on any trigger, including its cron
+# and workflow_dispatch. That state lives in GitHub's UI and is invisible when
+# reading this file, which has already misled at least one audit — hence this
+# banner. Re-enabling is a UI action; anyone doing so should first check that the
+# workflow still matches the current CI layout. See rustfs/backlog#1603.
+#
 name: minio-interop
 
 on:

.github/workflows/mint.yml

@@ -45,6 +45,13 @@
 # docker-capable self-hosted `dind-sm-standard-2` label was the alternative but
 # has fewer cores and reintroduces fleet-state risk for no reliability gain.
 
+# DISABLED. This workflow is switched off in the repository's Actions settings
+# (state: disabled_manually) and does not run on any trigger, including its cron
+# and workflow_dispatch. That state lives in GitHub's UI and is invisible when
+# reading this file, which has already misled at least one audit — hence this
+# banner. Re-enabling is a UI action; anyone doing so should first check that the
+# workflow still matches the current CI layout. See rustfs/backlog#1603.
+#
 name: mint
 
 on:

.github/workflows/nix-flake-update.yml

@@ -19,9 +19,12 @@ on:
   schedule:
     - cron: '0 5 * * 0' # Weekly on Sunday 05:00 UTC (staggered after the midnight ci/build crons)
 
+# GITHUB_TOKEN only needs to read the repository here: the branch push and the
+# pull request are both created by update-flake-lock using the
+# FLAKE_UPDATE_TOKEN PAT below, not by this token. Leaving write on it hands a
+# repo-write credential to an unattended weekly job that does not use it.
 permissions:
-  contents: write
-  pull-requests: write
+  contents: read
 
 concurrency:
   group: ${{ github.workflow }}-${{ github.ref }}

.github/workflows/nix.yml

@@ -12,6 +12,13 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
+# DISABLED. This workflow is switched off in the repository's Actions settings
+# (state: disabled_manually) and does not run on any trigger, including its cron
+# and workflow_dispatch. That state lives in GitHub's UI and is invisible when
+# reading this file, which has already misled at least one audit — hence this
+# banner. Re-enabling is a UI action; anyone doing so should first check that the
+# workflow still matches the current CI layout. See rustfs/backlog#1603.
+#
 name: Nix CI
 
 on:

.github/workflows/performance-ab.yml

@@ -22,6 +22,13 @@
 # a deliberate correctness cost (e.g. the #4221 fsync durability fix) is
 # recorded but does not block (rustfs/backlog#935 correction 1).
 
+# DISABLED. This workflow is switched off in the repository's Actions settings
+# (state: disabled_manually) and does not run on any trigger, including its cron
+# and workflow_dispatch. That state lives in GitHub's UI and is invisible when
+# reading this file, which has already misled at least one audit — hence this
+# banner. Re-enabling is a UI action; anyone doing so should first check that the
+# workflow still matches the current CI layout. See rustfs/backlog#1603.
+#
 name: Performance A/B
 
 on:

.github/workflows/schedule-failure-alert-drill.yml

@@ -24,6 +24,13 @@
 # The run itself is expected to end red (the forced failure); only the
 # alert-on-failure job result matters.
 
+# DISABLED. This workflow is switched off in the repository's Actions settings
+# (state: disabled_manually) and does not run on any trigger, including its cron
+# and workflow_dispatch. That state lives in GitHub's UI and is invisible when
+# reading this file, which has already misled at least one audit — hence this
+# banner. Re-enabling is a UI action; anyone doing so should first check that the
+# workflow still matches the current CI layout. See rustfs/backlog#1603.
+#
 name: Schedule Failure Alert Drill
 
 on:

.github/workflows/stale.yml

@@ -12,6 +12,13 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
+# DISABLED. This workflow is switched off in the repository's Actions settings
+# (state: disabled_manually) and does not run on any trigger, including its cron
+# and workflow_dispatch. That state lives in GitHub's UI and is invisible when
+# reading this file, which has already misled at least one audit — hence this
+# banner. Re-enabling is a UI action; anyone doing so should first check that the
+# workflow still matches the current CI layout. See rustfs/backlog#1603.
+#
 name: "Mark stale issues"
 on:
   schedule:

scripts/check_ci_paths_sync.sh

@@ -0,0 +1,83 @@
+#!/usr/bin/env bash
+# ci.yml's pull_request paths-ignore and ci-docs-only.yml's paths must be equal.
+#
+# ci-docs-only.yml exists to report the required checks for pull requests that
+# ci.yml skips. The two lists are the complement of each other, so any drift
+# breaks one of two ways, both silent:
+#
+#   - an entry only in ci.yml's paths-ignore: a PR touching only those files
+#     triggers neither workflow, nobody reports "Test and Lint" or "Quick
+#     Checks", and the PR waits on a required check forever;
+#   - an entry only in ci-docs-only.yml's paths: both workflows run, which is
+#     merely wasteful — but it also means the lists no longer describe the same
+#     intent, and the next edit is made against a wrong assumption.
+#
+# The push paths-ignore in ci.yml is deliberately NOT compared: no required
+# check is reported for push events, so it does not have to pair with anything.
+#
+# Also asserts ci-docs-only.yml still declares both companion job names, since a
+# rename there produces exactly the permanent-pending failure above.
+#
+# Usage: scripts/check_ci_paths_sync.sh
+set -euo pipefail
+
+cd "$(dirname "$0")/.."
+
+CI=".github/workflows/ci.yml"
+DOCS=".github/workflows/ci-docs-only.yml"
+
+# Print the quoted list items that follow $2 within the block introduced by $1.
+# Both files keep these as a flat list of quoted scalars, so no YAML parser is
+# needed and the script stays dependency-free like its check_* siblings.
+extract() {
+    local file="$1" event="$2" key="$3"
+    awk -v event="$event" -v key="$key" '
+        $0 ~ "^  " event ":[[:space:]]*$" { in_event = 1; next }
+        in_event && /^  [a-z_]+:[[:space:]]*$/ { in_event = 0 }
+        in_event && $0 ~ "^    " key ":[[:space:]]*$" { in_list = 1; next }
+        in_list {
+            if ($0 ~ /^      - /) {
+                item = $0
+                sub(/^      - /, "", item)
+                gsub(/^"|"$/, "", item)
+                print item
+                next
+            }
+            if ($0 !~ /^[[:space:]]*#/ && $0 !~ /^[[:space:]]*$/) in_list = 0
+        }
+    ' "$file" | sort
+}
+
+ci_list="$(extract "$CI" "pull_request" "paths-ignore")"
+docs_list="$(extract "$DOCS" "pull_request" "paths")"
+
+if [ -z "$ci_list" ] || [ -z "$docs_list" ]; then
+    echo "ERROR: could not read one of the path lists — did the file structure change?" >&2
+    echo "  $CI pull_request.paths-ignore: $(printf '%s' "$ci_list" | grep -c . || true) entries" >&2
+    echo "  $DOCS pull_request.paths: $(printf '%s' "$docs_list" | grep -c . || true) entries" >&2
+    exit 1
+fi
+
+status=0
+
+if ! diff_out="$(diff <(printf '%s\n' "$ci_list") <(printf '%s\n' "$docs_list"))"; then
+    echo "ERROR: $CI pull_request paths-ignore and $DOCS paths have drifted." >&2
+    echo "  '<' is only in $CI, '>' is only in $DOCS:" >&2
+    printf '%s\n' "$diff_out" | sed 's/^/    /' >&2
+    status=1
+fi
+
+for job_name in "Test and Lint" "Quick Checks"; do
+    if ! grep -q "name: ${job_name}\$" "$DOCS"; then
+        echo "ERROR: $DOCS no longer declares a job named '${job_name}'." >&2
+        echo "  It is a required status check; without a companion job here, a" >&2
+        echo "  docs-only PR waits on it forever." >&2
+        status=1
+    fi
+done
+
+if [ "$status" -ne 0 ]; then
+    exit 1
+fi
+
+echo "OK: ci.yml and ci-docs-only.yml path lists agree ($(printf '%s\n' "$ci_list" | wc -l | tr -d ' ') entries)"