index.js

const fs = require("fs");
const os = require("os");
const path = require("path");

const core = require("@actions/core");
const gh = require("@actions/github");
const tc = require("@actions/tool-cache");

// Leverage the GitHub Action environment variables to authenticate with GitHub
const octokit = new gh.getOctokit(process.env.GITHUB_TOKEN);

// getRelease returns the octokit release object for the given version
async function getRelease(version) {
  var release;
  try {
    if (version === "latest") {
      release = await octokit.rest.repos.getLatestRelease({
        owner: "hairyhenderson",
        repo: "gomplate",
      });
    } else {
        release = await octokit.rest.repos.getReleaseByTag({
          owner: "hairyhenderson",
          repo: "gomplate",
          tag: version,
        });
    }
  } catch (e) {
    core.setFailed(e);
  }
  return release
}

// arch in [arm, x32, x64...] (https://nodejs.org/api/os.html#os_os_arch)
// return value in [amd64, 386, arm]
function mapArch(arch) {
  const mappings = {
    x32: "386",
    x64: "amd64",
  };
  return mappings[arch] || arch;
}

// os in [darwin, linux, win32...] (https://nodejs.org/api/os.html#os_os_platform)
// return value in [darwin, linux, windows]
function mapOS(os) {
  const mappings = {
    win32: "windows",
  };
  return mappings[os] || os;
}

// getDownloadObject returns an object with the following properties:
//   url: the url to download the tool from
//   binPath: the local path to the downloaded tool
async function getDownloadObject(version) {
  const release = await getRelease(version);
  core.debug("release: " + release.data.name);
  const asset = release.data.assets.find((asset) =>
    asset.name.endsWith(
      `gomplate_${mapOS(os.platform())}-${mapArch(os.arch())}`
    )
  );
  core.debug("asset: " + asset)
  const url = asset.browser_download_url;
  const binPath = path.join("gomplate_linux-amd64");
  core.info("url: " + url);
  core.info("binPath: " + binPath);
  return { url, binPath };
}

// setup downloads the tool and installs it to the given path
async function setup() {
  try {
    // Get version of tool to be installed
    const version = core.getInput("gomplate-version");
    core.debug("version: " + version);

    // Download the specific version of the tool.
    const download = await getDownloadObject(version);
    const pathToCLI = await tc.downloadTool(
      download.url,
      process.env.RUNNER_TEMP + "/gomplate"
    );
    fs.chmodSync(pathToCLI, 0o755); // make the binary executable
    console.log("pathToCLI: " + pathToCLI);

    // Expose the tool by adding it to the PATH
    core.addPath(process.env.RUNNER_TEMP);
  } catch (e) {
    core.setFailed(e);
  }
}

export default setup;

setup();