feature: allow downloading of package by remote host

roles/_common/tasks/install.yml

@@ -46,12 +46,12 @@
     - install
     - "{{ ansible_parent_role_names | first | regex_replace(ansible_collection_name ~ '.', '') }}_install"
 
-- name: "Create localhost binary cache path"
+- name: "Create binary cache path on {{ 'localhost' if (_common_delegate_to_localhost | bool) else 'remote host'}}"
   ansible.builtin.file:
     path: "{{ _common_local_cache_path }}"
     state: directory
     mode: 0755
-  delegate_to: localhost
+  delegate_to: "{{ 'localhost' if (_common_delegate_to_localhost | bool) else omit }}"
   check_mode: false
   become: false
   tags:
@@ -78,7 +78,7 @@
       run_once: true
       when: (_common_checksums_url)
 
-    - name: "Download {{ __common_binary_basename }}"
+    - name: "Download {{ __common_binary_basename }} from {{ _common_binary_url }} on {{ 'localhost' if (_common_delegate_to_localhost | bool) else 'remote host'}}"
       ansible.builtin.get_url:
         url: "{{ _common_binary_url }}"
         dest: "{{ _common_local_cache_path }}/{{ _common_binary_name | default(__common_binary_basename) }}"
@@ -90,17 +90,18 @@
       retries: 5
       delay: 2
       # run_once: true  # <-- this can't be set due to multi-arch support
-      delegate_to: localhost
+      delegate_to: "{{ 'localhost' if (_common_delegate_to_localhost | bool) else omit }}"
       check_mode: false
 
-    - name: "Unpack binary archive {{ __common_binary_basename }}"
+    - name: "Unpack binary archive {{ __common_binary_basename }} on {{ 'localhost' if (_common_delegate_to_localhost | bool) else 'remote host'}}"
       ansible.builtin.unarchive:
         src: "{{ _common_local_cache_path }}/{{ __common_binary_basename }}"
         dest: "{{ _common_local_cache_path }}"
         mode: 0755
         list_files: true
         extra_opts: "{{ _common_binary_unarchive_opts | default(omit, true) }}"
-      delegate_to: localhost
+        remote_src: "{{ not (_common_delegate_to_localhost | bool) }}"
+      delegate_to: "{{ 'localhost' if (_common_delegate_to_localhost | bool) else omit }}"
       check_mode: false
       when: __common_binary_basename is search('\.zip$|\.tar\.gz$')
 
@@ -129,6 +130,7 @@
     mode: 0755
     owner: root
     group: root
+    remote_src: "{{ not (_common_delegate_to_localhost | bool) }}"
   loop: "{{ _common_binaries }}"
   become: true
   notify:

roles/_common/vars/main.yml

@@ -19,6 +19,7 @@ _common_tls_server_config: {}
 _common_http_server_config: {}
 _common_basic_auth_users: {}
 _common_web_listen_address: ""
+_common_delegate_to_localhost: "true"
 # Variables that should not be overwritten
 __common_binary_basename: "{{ _common_binary_url | urlsplit('path') | basename }}"
 __common_github_api_headers: "{{ {'GITHUB_TOKEN': lookup('ansible.builtin.env', 'GITHUB_TOKEN')} if (lookup('ansible.builtin.env', 'GITHUB_TOKEN')) else {} }}"

roles/node_exporter/defaults/main.yml

@@ -33,3 +33,8 @@ node_exporter_system_user: "{{ node_exporter_system_group }}"
 node_exporter_config_dir: "/etc/node_exporter"
 # Local path to stash the archive and its extraction
 node_exporter_local_cache_path: "/tmp/node_exporter-{{ ansible_system | lower }}-{{ _node_exporter_go_ansible_arch }}/{{ node_exporter_version }}"
+# If true (the default) we download node exporter archive and unpack it on localhost, before
+# uploading it to the remote host(s). If false we download and unpack the archive on the remote
+# host directly, which may be useful if the ansible controller host is slower (network-wise)
+# than the remote host.
+node_exporter_localhost_download: true

roles/node_exporter/meta/argument_specs.yml

@@ -82,3 +82,6 @@ argument_specs:
       node_exporter_config_dir:
         description: "Path to directory with node_exporter configuration"
         default: "/etc/node_exporter"
+      node_exporter_localhost_download:
+        description: "Determines if the node exporter package archive is downloaded and extracted on local (true) or remote host (false)"
+        default: true

roles/node_exporter/tasks/main.yml

@@ -21,6 +21,7 @@
     _common_system_user: "{{ node_exporter_system_user }}"
     _common_config_dir: "{{ node_exporter_config_dir }}"
     _common_binary_unarchive_opts: ['--strip-components=1']
+    _common_delegate_to_localhost: "{{ node_exporter_localhost_download }}"
   tags:
     - node_exporter_install