Move the release signing baseline to 3.1.6 and catch lightweight tags in CI

The 3.1.5 tag was created server-side by publishing the GitHub release,
which can only produce a lightweight ref, so it carries no signature and
git verify-tag fails on it. Rather than force-move a published tag, state
that signing starts at 3.1.6 and cut that tag locally with git tag -s
before the release is published.

vtag.yml now fails the run when the pushed tag is not a tag object, so the
same mistake shows up as a red check on the release instead of arriving as
a user report. The mirror step runs first, so v<tag> is still created; its
early "already exists" return became an else branch so the check is never
skipped.

https://github.com/acmesh-official/acme.sh/issues/7273

.github/workflows/vtag.yml

@@ -6,6 +6,9 @@ name: Mirror version tag
 # pointing to the same object, so both forms exist.
 # No retrigger loop: the tag filter never matches a "v"-prefixed tag, and
 # refs created with GITHUB_TOKEN do not fire workflows anyway.
+# The job mirrors first and then fails when the pushed tag is lightweight,
+# which is what the release form produces: that tag can never carry a
+# signature, so the failure has to be loud.
 
 on:
   push:
@@ -26,19 +29,39 @@ jobs:
           REPO: ${{ github.repository }}
           TAG: ${{ github.ref_name }}
         run: |
-          if gh api "repos/$REPO/git/ref/tags/v$TAG" >/dev/null 2>&1; then
-            echo "Tag v$TAG already exists, nothing to do."
-            exit 0
-          fi
           # Mirror the object the pushed tag actually points at: the commit
           # for a lightweight tag, the tag object itself for an annotated or
           # signed one. Pointing the mirror at the commit would strip the
           # signature, so "git verify-tag v3.1.3" would fail while
           # "git verify-tag 3.1.3" succeeds.
-          sha="$(gh api "repos/$REPO/git/ref/tags/$TAG" --jq .object.sha)"
+          _ref="$(gh api "repos/$REPO/git/ref/tags/$TAG" --jq '.object.sha + " " + .object.type')"
+          sha="${_ref%% *}"
+          objtype="${_ref##* }"
           if [ -z "$sha" ] || [ "$sha" = "null" ]; then
             echo "Could not resolve refs/tags/$TAG"
             exit 1
           fi
+          if gh api "repos/$REPO/git/ref/tags/v$TAG" >/dev/null 2>&1; then
+            echo "Tag v$TAG already exists, nothing to do."
+          else
             gh api "repos/$REPO/git/refs" -f ref="refs/tags/v$TAG" -f sha="$sha"
             echo "Created tag v$TAG -> $sha"
+          fi
+
+      - name: Check that the tag is signable
+        env:
+          GH_TOKEN: ${{ github.token }}
+          REPO: ${{ github.repository }}
+          TAG: ${{ github.ref_name }}
+        run: |
+          # A release published from the GitHub UI creates the tag server-side
+          # as a lightweight ref, which points straight at a commit and can
+          # never carry a signature (3.1.5 shipped that way, see issue 7273).
+          # The tag has to be created locally with "git tag -s" and pushed
+          # BEFORE the release is published, then selected on the release form.
+          objtype="$(gh api "repos/$REPO/git/ref/tags/$TAG" --jq .object.type)"
+          if [ "$objtype" != "tag" ]; then
+            echo "::error::refs/tags/$TAG points at a $objtype, not a tag object. It is a lightweight tag and carries no signature. Recreate it locally with 'git tag -s $TAG' and push it before publishing the release."
+            exit 1
+          fi
+          echo "refs/tags/$TAG is a tag object."

README.md

@@ -233,7 +233,7 @@ acme.sh -h
 
 #### 🔏 Verify a Release
 
-Release tags from `3.1.5` on are signed with the maintainer's SSH key. The
+Release tags from `3.1.6` on are signed with the maintainer's SSH key. The
 signing happens on the maintainer's machine, so the private key is never
 available to CI. The public half is [`allowed_signers`](allowed_signers) in
 this repository. From a clone:
@@ -243,7 +243,7 @@ git config gpg.ssh.allowedSignersFile allowed_signers
 ```
 
 ```bash
-git verify-tag 3.1.5
+git verify-tag 3.1.6
 ```
 
 The signature covers the tag object, which pins the commit and therefore the
@@ -251,10 +251,10 @@ whole tree, so a good signature verifies every file at that release and no
 separate tarball checksum is needed. Build a tarball from the verified tag:
 
 ```bash
-git archive --format=tar.gz --prefix=acme.sh-3.1.5/ 3.1.5 > acme.sh-3.1.5.tar.gz
+git archive --format=tar.gz --prefix=acme.sh-3.1.6/ 3.1.6 > acme.sh-3.1.6.tar.gz
 ```
 
-> ⚠️ Tags up to `3.1.4` predate the signing key and are unsigned.
+> ⚠️ Tags up to `3.1.5` are unsigned.
 
 ---
 

acme.sh

@@ -1,6 +1,6 @@
 #!/usr/bin/env sh
 
-VER=3.1.5
+VER=3.1.6
 
 PROJECT_NAME="acme.sh"