index.js

const core = require("@actions/core");
const exec = require("@actions/exec");
const io = require("@actions/io");
const fs = require("fs");

const values_list = ["PRIVATE_KEY", "USERNAME", "IP", "PORT", "SHELL"];

// get input values
let { PRIVATE_KEY, USERNAME, IP, PORT, SHELL } = (function () {
  let values = [];
  values_list.forEach((value) => {
    values[value] = core.getInput(value);
  });
  return values;
})();

function create_file(path, content) {
  fs.appendFile(path, content, (err) => {
    if (err) throw err;
  });
}

async function run() {
  try {
    if (PRIVATE_KEY.trim().length == 0) {
      throw "PRIVATE_KEY cannot be empty";
    }
    if (USERNAME.trim().length == 0) {
      throw "USERNAME cannot be empty";
    }
    if (IP.trim().length == 0) {
      throw "IP cannot be empty";
    }
    if (PORT.trim().length == 0) {
      PORT = 22;
    } else {
      PORT = parseInt(PORT);
      if (isNaN(PORT)) {
        throw "invalid PORT";
      }
    }

    // get home dir from environment
    const HOME = process.env["HOME"];
    core.info(HOME);

    // config ssh
    await io.mkdirP(HOME + "/.ssh");
    await create_file(HOME + "/.ssh/deploy.key", PRIVATE_KEY);
    await exec.exec(`ls ${HOME}/.ssh`);
    await exec.exec(`chmod 600 ${HOME}/.ssh/deploy.key`);
    await create_file(
      HOME + "/.ssh/config",
      `Host server\n\
    HostName ${IP}\n\
    User ${USERNAME}\n\
    Port ${PORT}\n\
    IdentityFile ~/.ssh/deploy.key\n\
    StrictHostKeyChecking no\n`
    );

    await exec.exec("ls -al");

    // check if SHELL is not null
    if (SHELL.trim().length != 0) {
      let shells = SHELL.split("\n");
      for (let shell of shells) {
        core.info(shell);
        await exec.exec("ssh server " + shell);
      }
    }
  } catch (error) {
    core.setFailed(error);
  }
}

run();