Fix version regex to pick 'v*' tags

Change-Id: I783d25439ff3b47781d206f7d72fba7575add140

roles/tobiko-ensure-docker-compose/defaults/main.yaml

@@ -1,5 +1,3 @@
 ---
 
 docker_compose_executable: /usr/local/bin/docker-compose
-docker_compose_install_using_pip: true
-docker_compose_install_using_curl: not docker_compose_install_using_pip

roles/tobiko-ensure-docker-compose/tasks/main.yaml

@@ -1,26 +1,40 @@
 ---
 
-- name: "Install latest Docker compose with Pip"
-  become: true
-  shell: |
-    set -x
-    python3 -m pip install docker-compose
-  when: docker_compose_install_using_pip
+- block:
+  - name: install latest Docker compose using pip
+    become: true
+    shell: |
+      set -x
+      python3 -m pip install docker-compose
 
+  - name: get docker compose location path
+    shell: which docker-compose
+    register: get_docker_compose_path
 
-- name: "Install latest Docker compose with Curl"
-  become: true
-  shell: |
-    set -x
-    VERSION=$(
-      git ls-remote https://github.com/docker/compose |
-      grep refs/tags |
-      grep -oE "[0-9]+\.[0-9][0-9]+\.[0-9]+$" |
-      sort --version-sort |
-      tail -n 1)
-    ARCH=$(uname -s)-$(uname -m)
-    URL=https://github.com/docker/compose/releases/download/${VERSION}/docker-compose-${ARCH}
-    mkdir -p $(dirname '{{ docker_compose_executable }}')
-    curl -L ${URL} > '{{ docker_compose_executable }}'
-    chmod +x '{{ docker_compose_executable }}'
-  when: docker_compose_install_using_curl
+  - name: save docker compose path fact
+    set_fact:
+      docker_compose_executable: '{{ get_docker_compose_path.stdout.strip() }}'
+
+  - debug: var=docker_compose_executable
+
+  rescue:
+  - name: install latest Docker compose with Curl
+    become: true
+    shell: |
+      set -x
+      VERSION=$(
+        git ls-remote https://github.com/docker/compose |
+        awk '/refs\/tags\/v/{print $2}' |
+        sort --version-sort |
+        tail -n 1)
+      ARCH=$(uname -s)-$(uname -m)
+      URL=https://github.com/docker/compose/releases/download/${VERSION}/docker-compose-${ARCH}
+      mkdir -p $(dirname '{{ docker_compose_executable }}')
+      curl -L ${URL} > '{{ docker_compose_executable }}'
+      chmod +x '{{ docker_compose_executable }}'
+
+  - name: save docker compose path fact
+    set_fact:
+      docker_compose_executable: '{{ docker_compose_executable }}'
+
+  - debug: var=docker_compose_executable