Update data in field pre hook

[grimabe]

In my user model I have a password field that I would like to hash when the user is created or updated.
I already achieve to do it with mongoose pre save hook.

But it appears to be only working when creating the document because the update mutation doesn't seems to use the model save method.

So I thought about using the field pre hook like below but I don't know how to update the value.

        password: {
            type: String,
            required: true,
            hooks: {
                pre: (next, root, args, request) => {
                    //replace  with hashed password
                    next();
                },
                post: (next) => next(`********`)
            }
        },

Is there a way to do that ?

Thank you

[tothandras]

Hi @grimabe,
you can change the arguments like:

pre: (next, root, args, ...rest) => {
   // replace  with hashed password
   args.password = hash(args.password)
   next(root, args, ...rest)
}

Give it a try and let me know if it worked or not!

[grimabe]

Hi @tothandras,
Thanks for the answer, I tried exactly the code you wrote but the field is still not modified in the database.

Do you have something else to try ?

[tothandras]

Hi @grimabe,
sorry for the delay. I've just realised that the field hooks are for queries, not mutations. So this is what you need to do (using the example in the project) to change arguments for mutations:

const hooks = {
  mutation: {
    pre(next, args, context, info) {
      if (info.fieldName === 'updateUser') {
        args.name += ' MutationPreHook';
      }
      next(args, context, info);
    }
  }
};
const schema = getSchema([User], { hooks });

Let's see a user:

query {
  users {
    id,
    name
  }
}

Update its name:

mutation {
  updateUser(input: {id: "VXNlcjo1Nzk3YTA0NDdjZjhlMDQ4ODY5ZDRlNGQ=", name: "UserUpdated", clientMutationId: "0"}) {
    changedUser {
      id,
      name
    }
  }
}