Reusing auth logic in different firebase cloud functions-CodePudding

I have these three callable functions that all do an auth check before running their main logic. This doesn't seem very DRY and I would like to know if there was a more clever way to reuse this auth logic?

exports.addComment = functions.https.onCall(async (data, { auth }) => {
  if (auth) {
    //logic to add comment
  } else {
    throw new functions.https.HttpsError(
      "failed-precondition",
      "You must be authenticated"
    );
  }
});

exports.deleteComment = functions.https.onCall(async (data, { auth }) => {
  if (auth) {
    //logic to delete comment
  } else {
    throw new functions.https.HttpsError(
      "failed-precondition",
      "You must be authenticated"
    );
  }
});

exports.updateComment = functions.https.onCall(async (data, { auth }) => {
  if (auth) {
    //logic to update comment
  } else {
    throw new functions.https.HttpsError(
      "failed-precondition",
      "You must be authenticated"
    );
  }
});

CodePudding user response：

i would use here decorator for your scenario.

basically decorator is a function which receives a function and extend it's functionality by wrapping it.

so it would look something like that:

function authDecorator(functionWithLogic) {

   let innerFunc = () => {
      if (auth) {
      return functionWithLogic()
      } else {
      throw new functions.https.HttpsError(
        "failed-precondition",
        "You must be authenticated"
      );
    }
   return innerFunc

}

you can also extend it and pass relevant params to it as needed