Match string with values from array in express-validation

Question

I am using express-validator to validate input to my API, but I have some problems understanding the matches function. I basically need to be able to figure out if a string matches any of the values in an array of accepted values, like shown below, but it doesn't seem to work. Any suggestions?

var schema = {
  "role": {
    in: 'body',
    matches: {
      options: ["administrator", "editor", "contributor", "user"],
      errorMessage: "Invalid role"
    }
  }
}

req.check(schema)

Answer 1

The matches.options constructs a regex. You can pass in your regex as the first element of the array. Try this:

var schema = {
  "role": {
    in: 'body',
    matches: {
      options: [/\b(?:administrator|editor|contributor|user)\b/],
      errorMessage: "Invalid role"
    }
  }
}

Answer 2

As an alternative you can use this schema:

 var schema = {
  "role": {
    in: 'body',
    isIn: {
      options: [["administrator", "editor", "contributor", "user"]],
      errorMessage: "Invalid role"
    }
  }
}

More on this issue.