同步猫鼬和nodejs操作

Question

As a part of bootcamp course I am going through, I am learning building restful API's along with Mongoose, GraphQL and NodeJs.

Here is my code

resolve (parent, args) {

                let books = new book({
                    name: args.name, 
                    genre: args.genre,
                    authorName: args.authorName
                })    

                let author = new Author({ 
                    name: args.authorName
                })

                book.find( 
                    {
                        name: args.name
                    }, function(error, results) {
                        if (results.length == 0 ) {
                            Author.find(
                                {
                                  name: args.authorName
                                },
                                function (err, result) {
                                    if (result.length == 0) {    
                                    author.save()
                                  }
                                 })
                              }
                              books.save()  
                            })
                    return books
            }

Now, While this works, the problem is that books and author are linked together in GraphQL query and when running the query.

Putting aside the entire story part. I want to return books (or let's say I want to do return books.save()) when the operation in my mongoose is over (since mongoose is async)

I stupidly thought about doing something like this in the end

             books.save()  
                            }).then(() => {
                    return books
                })
            }

but then return books here is returning the promise and not the resolve.

Question: How can I return resolve after my MongoDB operation is over? (or in sync with MongoDB)

Answer 1

1. you need to put the async on the function declare.
2. when you call find on the model, use await instead of passing function callback on find()

Ex: const books = await book.find({name: args.name}) which will return array of books or null