index.js

const core = require('@actions/core');
const SplitFactory = require('@splitsoftware/splitio').SplitFactory;

const checkInputParam = function (param, errMsg) {
  if (param == '') {
    core.setFailed(errMsg);
    throw errMsg;
  }
};

try {
  const apiKey = core.getInput('api-key');
  checkInputParam(apiKey, 'API Key is required');
  core.debug('api-key: ' + apiKey.substring(0, 5) + '...');

  const key = core.getInput('key');
  checkInputParam(key, 'User/Evaluation key is required');
  core.debug('key: ' + key);

  const splits = core.getMultilineInput('splits');
  core.debug('Splits: ' + splits);

  var factory;
  if (apiKey == 'localhost') {
    factory = SplitFactory({
      core: {
        authorizationKey: apiKey,
      },
      features: '.github/splitio/.split',
    });
  } else {
    factory = SplitFactory({
      core: {
        authorizationKey: apiKey,
      },
    });
  }

  var client = factory.client();

  client.on(client.Event.SDK_READY, async function () {
    var result = client.getTreatments(key, splits);

    for (const splitName in result) {
      if (Object.hasOwnProperty.call(result, splitName)) {
        const treatment = result[splitName];
        // Export env var
        core.exportVariable(splitName, treatment);
      }
    }

    // Set the step output
    //core.setOutput('result', JSON.stringify(result));
    core.setOutput('result', result);

    await client.destroy(); // flush the impressions
    client = null;
  });
} catch (error) {
  core.setFailed(error.message);
}