name: Go Setup + S3 Caching
description: Install Go and configure tailscale/go-cache-plugin for Go builds with an S3-compatible backend in Gitea Actions
author: eric

inputs:
  go-version:
    description: Go version to install (e.g., 1.22, 1.24, stable)
    default: stable
    required: false
  cache:
    description: Enable S3 go-cache-plugin.
    default: "true"
    required: false
  go-cache-plugin-version:
    description: go-cache-plugin version tag or latest.
    default: latest
    required: false
  s3-bucket:
    description: S3 bucket for go cache. Leave empty to use local caching only.
    default: ""
    required: false
  s3-region:
    description: S3 region name.
    default: us-east-1
    required: false
  s3-endpoint:
    description: Optional S3-compatible endpoint URL, for example https://s3.example.com.
    default: ""
    required: false
  s3-path-style:
    description: Enable path-style S3 addressing (useful for MinIO or custom Ceph setups).
    default: "false"
    required: false
  cache-dir:
    description: Local cache directory for go-cache-plugin before uploading/downloading from S3.
    default: ~/.cache/go-cache
    required: false

runs:
  using: composite
  steps:
    - name: Setup Go
      uses: https://gitea.com/actions/setup-go@v4
      with:
        go-version: ${{ inputs.go-version }}
        # Disable default setup-go local cache if we are using our custom S3 caching
        cache: ${{ inputs.s3-bucket == '' }}

    - name: Install go-cache-plugin
      if: ${{ inputs.cache == 'true' && inputs.s3-bucket != '' }}
      shell: bash
      run: |
        echo "Installing custom Cloudflare-compatible go-cache-plugin..."
        cd "${{ github.action_path }}/../../../go-cache-plugin-src"
        go build -o $HOME/go/bin/go-cache-plugin ./cmd/go-cache-plugin

    - name: Configure Go Cache
      if: ${{ inputs.cache == 'true' && inputs.s3-bucket != '' }}
      shell: bash
      run: |
        # Expand cache-dir path
        CACHE_DIR=$(eval echo "${{ inputs.cache-dir }}")
        mkdir -p "$CACHE_DIR"
        
        # Build GOCACHEPROG command with verbose debug logging and metrics
        CMD="$HOME/go/bin/go-cache-plugin -v --metrics --debug=1 --cache-dir=$CACHE_DIR --bucket=${{ inputs.s3-bucket }} --region=${{ inputs.s3-region }}"
        
        if [ -n "${{ inputs.s3-endpoint }}" ]; then
          CMD="$CMD --s3-endpoint-url=${{ inputs.s3-endpoint }}"
        fi
        
        if [ "${{ inputs.s3-path-style }}" = "true" ]; then
          CMD="$CMD --s3-path-style=true"
        fi
        
        echo "Configuring GOCACHEPROG: $CMD"
        echo "GOCACHEPROG=$CMD" >> "$GITHUB_ENV"
        
        # Ensure GOEXPERIMENT=cacheprog is enabled ONLY for Go 1.21-1.23 compatibility
        GO_VER=$(go env GOVERSION | grep -oE '[0-9]+\.[0-9]+' | head -n 1)
        echo "Detected Go version: $GO_VER"
        if [ "$GO_VER" = "1.21" ] || [ "$GO_VER" = "1.22" ] || [ "$GO_VER" = "1.23" ]; then
          echo "Enabling GOEXPERIMENT=cacheprog for compatibility"
          echo "GOEXPERIMENT=cacheprog" >> "$GITHUB_ENV"
        else
          echo "GOEXPERIMENT=cacheprog is not needed or supported in Go 1.24+"
        fi

        # Diagnose secret population
        echo "Diagnosing secrets..."
        echo "SCCACHE_AWS_ACCESS_KEY_ID length: ${#SCCACHE_AWS_ACCESS_KEY_ID}"
        echo "SCCACHE_AWS_SECRET_ACCESS_KEY length: ${#SCCACHE_AWS_SECRET_ACCESS_KEY}"

        # Align with actions-rust: map SCCACHE secrets to standard AWS variables
        if [ -n "$SCCACHE_AWS_ACCESS_KEY_ID" ] && [ -z "${AWS_ACCESS_KEY_ID:-}" ]; then
          echo "AWS_ACCESS_KEY_ID=$SCCACHE_AWS_ACCESS_KEY_ID" >> "$GITHUB_ENV"
        fi
        if [ -n "$SCCACHE_AWS_SECRET_ACCESS_KEY" ] && [ -z "${AWS_SECRET_ACCESS_KEY:-}" ]; then
          echo "AWS_SECRET_ACCESS_KEY=$SCCACHE_AWS_SECRET_ACCESS_KEY" >> "$GITHUB_ENV"
        fi