Add support for a binaries_url parameter (#22)

README.md

@@ -29,6 +29,7 @@ jobs:
       with:
         config: ${{ secrets.KUBE_CONFIG_DATA }}
         version: v1.21.0 # specify kubectl binary version explicitly
+        binaries-url: "https://dl.k8s.io/release/v1.21.0/bin/linux/amd64/kubectl" # specify the download url explicitly
         command: rollout status deployment/my-app
 ```
 
@@ -44,4 +45,6 @@ cat $HOME/.kube/config | base64
 
 `version`: The kubectl version with a 'v' prefix, e.g. `v1.21.0`. It defaults to the latest kubectl binary version available.
 
+`binaries-url`: The url to download the binaries from. It defaults to the official release page if empty.
+
 **Note**: Do not use kubectl config view as this will hide the certificate-authority-data.

action.yml

@@ -7,6 +7,7 @@ runs:
     - ${{ inputs.version }}
     - ${{ inputs.config }}
     - ${{ inputs.command }}
+    - ${{ inputs.binaries-url }}
 branding:
   icon: 'terminal'
   color: 'blue'
@@ -21,3 +22,6 @@ inputs:
   command:
     description: 'kubectl command to run, without the kubectl, e.g. `get pods`'
     required: true
+  binaries-url:
+    description: 'Url to download the binaries from, defaults to the official dl.k8s.io url' 
+    required: false

entrypoint.sh

@@ -5,14 +5,21 @@ set -e
 version="$1"
 config="$2"
 command="$3"
+binaries_url="$4"
 
-if [ "$version" = "latest" ]; then
-  version=$(curl -Ls https://dl.k8s.io/release/stable.txt)
-fi
+if [ -n "$binaries_url" ]; then
+  if [ "$version" = "latest" ]; then
+    version=$(curl -Ls https://dl.k8s.io/release/stable.txt)
+  fi
+
+  echo "using kubectl@$version"
 
-echo "using kubectl@$version"
+  curl -sLO "https://dl.k8s.io/release/$version/bin/linux/amd64/kubectl" -o kubectl
+else
+  echo "downloading kubectl binaries from $binaries_url"
+  curl -sLO $binaries_url -o kubectl
+fi
 
-curl -sLO "https://dl.k8s.io/release/$version/bin/linux/amd64/kubectl" -o kubectl
 chmod +x kubectl
 mv kubectl /usr/local/bin