GUIDE: Using Switch Statement

[dynabler]

Scenario: You want to check for data, but not save the actual data. Instead, you want to save it as your interpretation of data.

For example: You need to know if a page actually exists, but the server doesn't give a hard 404. It rather gives a soft 404 “page does not exist”.

When scraping this type of pages, your final JSON will have status: page does not exist. We want it to be more clean.

The following example checks Twitter for account status and outputs a JSON with status as we see fit.

export default function({ doc }) {
  const name = doc.find('account_username');
  const wrong = doc.find('span:contains("This account doesn’t exist")').text();
  const suspended = doc.find('title').text();
  const locked = doc.find('span:contains("These posts are protected")').text();

  switch(true) {
    case (wrong == "This account doesn’t exist"): {
      return {
        name: name.text().trim(),
        status: "wrong",
      }
    break;
    }
    case (suspended == "Log in to X / X"): {
      return {
        name: name.text().trim(),
        status: "suspended",
      }
    break;
    }
    case (locked == "These posts are protected"): {
      return {
        name: name.text().trim(),
        status: "private",
      }
    break;
    } 
    default: {
      return {
        name: name.text().trim(),
        status: "active",
      }
    }
  }
}

Using a JavaScript Switch statement, we can return/save data as we see fit.