Make OpenWhisk CLI available only via redirect

As was already done with the iOS starter app and the blackbox SDK,
switch to making the cli binaries available via a redirect to the
openwhisk-cli release page instead of copying cli binaries into
the edge container.  As discussed in issue apache#2152 this eliminates
the need for a custom OpenWhisk edge image for downstream deployments.

Also update GoCLINginxTests to check for redirects instead of direct
downloads and remove the cli role and related variable definitions
from ansible.

ansible/edge.yml

@@ -1,10 +1,8 @@
 ---
 # This playbook deploys Openwhisk Edge servers.
 # The edge is usually populated with NGINX serving as proxy.
-# The CLI also gets built and published for downloading from NGINX.  
-# SDKs for blackbox and iOS get published to NGINX also.
+# The CLI and SDKs for blackbox and iOS are available via redirect
 
 - hosts: edge
   roles:
   - nginx
-  - cli

ansible/group_vars/all

@@ -249,7 +249,6 @@ sdk:
 
 cli:
   path: "{{ openwhisk_home }}/bin/wsk"
-  nginxdir: "{{ nginx.confdir }}/cli/go/download"
   dir:
     become: "{{ cli_dir_become | default(false) }}"
 
@@ -290,41 +289,16 @@ catalog_repos:
     version: "HEAD"
     repo_update: "no"
 
+# The version of the openwhisk cli to which we will redirect download requests
 openwhisk_cli_tag: "{{ lookup('ini', 'git_tag section=openwhisk-cli file={{ openwhisk_home }}/ansible/files/package-versions.ini') }}"
 
-# The openwhisk_cli is used to determine how to install the OpenWhisk CLI. The
-# installation_mode can be specified into two modes: remote and local.
-# The mode remote means to download the available binaries from the releases page
-# of the official openwhisk cli repository. The mode local means to build the binaries
-# locally in a directory and get them from the local directory. The default value
-# for openwhisk is local.
-#
-# The name specifies the package name of the binaries in remote mode.
-#
-# The dest_name specifies the package name of the binaries in Nginx in remote mode.
-#
-# The location specifies the official website where Openwhisk CLI is hosted in
-# remote mode or location to save the binaries of the OpenWhisk CLI in local mode.
-#
-
-openwhisk_cli:
-  installation_mode: "{{ cli_installation_mode | default('remote') }}"
-  local:
-    location: "{{ openwhisk_cli_home }}/bin"
-  remote:
-    name: OpenWhisk_CLI
-    dest_name: OpenWhisk_CLI
-    location: "https://github.com/apache/incubator-openwhisk-cli/releases/download/{{ openwhisk_cli_tag }}"
-
-# The list of operating systems for which openwhisk cli binaries are downloaded,
-# if the installation_mode is remote.
+# The list of operating systems for which openwhisk cli binaries are available,
 cli_os:
   - linux
   - mac
   - windows
 
-# The list of architectures for which openwhisk cli binaries are downloaded,
-# if the installation_mode is remote.
+# The list of architectures for which openwhisk cli binaries are available,
 cli_arch:
   - amd64
   - 386

ansible/roles/nginx/templates/nginx.conf.j2

@@ -90,9 +90,18 @@ http {
             return 301 https://github.com/apache/incubator-openwhisk-client-swift/releases/download/0.2.3/starterapp-0.2.3.zip;
         }
 
+        # redirect requests for specific binaries to the matching one from the {{ openwhisk_cli_tag }} openwhisk-cli release.
+{% for os in cli_os %}
+    {% for arch in cli_arch %}
+        location /cli/go/download/{{ os }}/{{ arch }} {
+            return 301 https://github.com/apache/incubator-openwhisk-cli/releases/download/{{ openwhisk_cli_tag }}/OpenWhisk_CLI-{{ openwhisk_cli_tag }}-{{ os }}-{{ arch }}.{% if os == 'linux' %}tgz{% else %}zip{% endif %};
+        }
+    {% endfor %}
+{% endfor %}
+
+        # redirect top-level cli downloads to the {{ openwhisk_cli_tag }} openwhisk-cli release.
         location /cli/go/download {
-            autoindex on;
-            root /etc/nginx;
+            return 301 https://github.com/apache/incubator-openwhisk-cli/releases/{{ openwhisk_cli_tag }};
         }
     }
 }