How should I dry up the following code?

Question

I'm using superagent on a node client to fire POST or PATCH requests like so (it's ugly!):

Between the two code blocks in if-else the only difference is the http verb and the API endpoint, which in case of patch request also has a /:id appended to the url.

if ( typeof resourceId === 'undefined' ){
  request
    .post('http://localhost:8080/api/resources/')
    .send(JSON.stringify(resource_json))
    .set('Accept', 'application/json')
    .set('Content-Type', 'application/json')
    .set('Authorization', 'Token token=3S4pREbMkMoEGG6zHeUJ7Qtt')
    .end(function(err, res) {
      if (!err && res.ok) {
        console.log(chalk.bold.cyan('Resource created successfully'));
        packageJson.resource_id = res.body.id;
        fs.writeFileSync('package.json', JSON.stringify(packageJson));
        process.exit(0);
      }

      var errorMessage;

      if (res && res.status === 401) {
        errorMessage = "Authentication failed! Bad username/password?";
      } else if (err) {
        errorMessage = err;
      } else {
        errorMessage = res.text;
      }
      console.error(chalk.red(errorMessage));
      process.exit(1);
    });
  } else {
  request
    .patch('http://localhost:8080/api/reources/' + resourceId)
    .send(JSON.stringify(resource_json))
    .set('Accept', 'application/json')
    .set('Content-Type', 'application/json')
    .set('Authorization', 'Token token=3S4pREbMkMoEGG6zHeUJ7Qtt')
    .end(function(err, res) {
      if (!err && res.ok) {
        console.log(chalk.bold.cyan('Resource created successfully'));
        packageJson.book_id = res.body.id;
        fs.writeFileSync('package.json', JSON.stringify(packageJson));
        process.exit(0);
      }

      var errorMessage;

      if (res && res.status === 401) {
        errorMessage = "Authentication failed! Bad username/password?";
      } else if (err) {
        errorMessage = err;
      } else {
        errorMessage = res.text;
      }
      console.error(chalk.red(errorMessage));
      process.exit(1);
    });

  }

How can I DRY this up?

Answer 1

Methods can be accessed through a variable.

const baseUrl = 'http://localhost:8080/api/resources/';
const isNew = undefined === resourceId;
const method = isNew ? 'post' : 'patch';
const url = isNew ? baseUrl : basseUrl + resourceId;

request[method](url).send().end();

Or more readable.

const baseUrl = 'http://localhost:8080/api/resources/';
const isNew = undefined === resourceId;
let method, url;

if(isNew) {
    method = 'post'
    url = baseUrl;
} else {
    method = 'patch'
    url = baseUrl + resourceId;
}

request[method](url).send().end();