Merge pull request #5509 from RussellAult/action-without-api

`fluxcd/flux2/action`: Determine latest version without using GitHub API

action/action.yml

@@ -16,23 +16,24 @@ inputs:
     description: "Alternative location for the Flux binary, defaults to path relative to $RUNNER_TOOL_CACHE."
     required: false
   token:
-    description: "Token used to authentication against the GitHub.com API. Defaults to the token from the GitHub context of the workflow."
+    description: "Token used to authenticate against the GitHub.com API."
     required: false
 runs:
   using: composite
   steps:
     - name: "Download the binary to the runner's cache dir"
       shell: bash
+      env:
+        VERSION: "${{ inputs.version }}"
+        FLUX_TOOL_DIR: "${{ inputs.bindir }}"
+        TOKEN: "${{ inputs.token }}"
       run: |
-        VERSION=${{ inputs.version }}
-
-        TOKEN=${{ inputs.token }}
-        if [[ -z "$TOKEN" ]]; then
-          TOKEN=${{ github.token }}
-        fi
-
         if [[ -z "$VERSION" ]] || [[ "$VERSION" = "latest" ]]; then
-          VERSION=$(curl -fsSL -H "Authorization: token ${TOKEN}" https://api.github.com/repos/fluxcd/flux2/releases/latest | grep tag_name | cut -d '"' -f 4)
+          if [[ "${TOKEN}" != '' ]]; then
+            VERSION=$(curl -fsSL -H "Authorization: token ${TOKEN}" https://api.github.com/repos/fluxcd/flux2/releases/latest | grep tag_name | cut -d '"' -f 4)
+          else
+            VERSION=$(curl -w "%{url_effective}\n" -IsSL https://github.com/fluxcd/flux2/releases/latest -o /dev/null | sed 's$^.*/$$')
+          fi
         fi
         if [[ -z "$VERSION" ]]; then
           echo "Unable to determine Flux CLI version"
@@ -59,7 +60,6 @@ runs:
             FLUX_EXEC_FILE="${FLUX_EXEC_FILE}.exe"
         fi
 
-        FLUX_TOOL_DIR=${{ inputs.bindir }}
         if [[ -z "$FLUX_TOOL_DIR" ]]; then
           FLUX_TOOL_DIR="${RUNNER_TOOL_CACHE}/flux2/${VERSION}/${OS}/${ARCH}"
         fi