Download the uv build the Pi can actually run

Raspberry Pi OS ships a 64-bit kernel with a 32-bit userland, so uname -m - and
therefore ansible_architecture - reports aarch64 on a box whose /bin/ls is
ELF32 ARM and which has no /lib/ld-linux-aarch64.so.1. The aarch64 uv tarball
unpacked happily and then failed three tasks later with

    /usr/local/bin/uv: No such file or directory

which is the dynamic loader missing, not the file, and points at entirely the
wrong thing. Pick the target triple from ansible_userspace_bits instead, which
is the fact that tells the truth, and key the install directory on the triple as
well as the version - otherwise `creates:` would keep a wrong-architecture
binary in place forever. Then run `uv --version` right after installing it, so a
bad download fails where the cause is visible.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

roles/pi_musicmouse/defaults/main.yml

@@ -8,6 +8,21 @@ pi_musicmouse_repo: "ssh://git@git.bauer.tech:2222/martin/musicmouse.git"
 pi_musicmouse_python_version: "3.13"
 pi_musicmouse_uv_version: "0.12.10"
 
+# Which uv build to download. Raspberry Pi OS ships a 64-bit kernel with a 32-bit
+# userland, so `uname -m` (and therefore ansible_architecture) says aarch64 on a box
+# that can only run armhf binaries - the aarch64 build installs fine and then fails to
+# exec with "No such file or directory", which is the dynamic loader missing, not the
+# file. ansible_userspace_bits is the fact that tells the truth.
+pi_musicmouse_uv_target: >-
+  {{ 'armv7-unknown-linux-gnueabihf'
+     if (ansible_architecture in ['aarch64', 'armv7l', 'armv6l'] and ansible_userspace_bits == '32')
+     else _pi_musicmouse_uv_targets[ansible_architecture] }}
+_pi_musicmouse_uv_targets:
+  aarch64: aarch64-unknown-linux-gnu
+  armv7l: armv7-unknown-linux-gnueabihf
+  armv6l: armv7-unknown-linux-gnueabihf
+  x86_64: x86_64-unknown-linux-gnu
+
 # Where to check out the repo on the *control machine* to build the frontend (npm isn't
 # installed on the Pi - see README). Keyed by version so different hosts on different
 # versions don't clobber each other's build.

roles/pi_musicmouse/tasks/main.yml

@@ -11,21 +11,21 @@
 
 - name: Ensure uv install directory exists
   ansible.builtin.file:
-    path: "/opt/uv-{{ pi_musicmouse_uv_version }}"
+    path: "/opt/uv-{{ pi_musicmouse_uv_version }}-{{ pi_musicmouse_uv_target }}"
     state: directory
     mode: "0755"
 
 - name: Download and extract uv {{ pi_musicmouse_uv_version }}
   ansible.builtin.unarchive:
-    src: "https://github.com/astral-sh/uv/releases/download/{{ pi_musicmouse_uv_version }}/uv-aarch64-unknown-linux-gnu.tar.gz"
+    src: "https://github.com/astral-sh/uv/releases/download/{{ pi_musicmouse_uv_version }}/uv-{{ pi_musicmouse_uv_target }}.tar.gz"
-    dest: "/opt/uv-{{ pi_musicmouse_uv_version }}"
+    dest: "/opt/uv-{{ pi_musicmouse_uv_version }}-{{ pi_musicmouse_uv_target }}"
     remote_src: true
     extra_opts: ["--strip-components=1"]
-    creates: "/opt/uv-{{ pi_musicmouse_uv_version }}/uv"
+    creates: "/opt/uv-{{ pi_musicmouse_uv_version }}-{{ pi_musicmouse_uv_target }}/uv"
 
 - name: Symlink uv/uvx into /usr/local/bin
   ansible.builtin.file:
-    src: "/opt/uv-{{ pi_musicmouse_uv_version }}/{{ item }}"
+    src: "/opt/uv-{{ pi_musicmouse_uv_version }}-{{ pi_musicmouse_uv_target }}/{{ item }}"
     dest: "/usr/local/bin/{{ item }}"
     state: link
     force: true
@@ -33,6 +33,12 @@
     - uv
     - uvx
 
+- name: Verify uv runs on this host
+  ansible.builtin.command:
+    cmd: /usr/local/bin/uv --version
+  register: pi_musicmouse_uv_version_out
+  changed_when: false
+
 - name: Checkout Musicmouse repo
   ansible.builtin.git:
     repo: "{{ pi_musicmouse_repo }}"