GraphQL Tutorial #17 - Mongoose Models

Key Takeaways

alright then so now we've created an instance of MongoDB online and we've connected to that database now before we start putting data in the database what we need to do is create a model and schema for each data type that will be storing inside that database now I don't want you to get confused with a mongoose schema on MongoDB schema that we're going to create for our data that's being stored in a database and our schema which we pass through in to this thing right here for graph QL this schema is defining our graph and the object types on that graph our mongoose schema is going to define the data that's actually being stored in MongoDB so that MongoDB understands that data right it knows what to expect so again try not to get those two things mixed up they're two different schemas so what I'm going to do first of all is right-click server create a new folder over here and this is going to be called models so this will store our mongoose models are our MongoDB models inside and we're going to make two files one for a book model so I'm going to call this book Jas and also another called author Jas for our author model right because we're going to store two different types of data they're going to be two different collections on MongoDB so let us tackle the book model first of all now the first thing we need to do is create a constant called Mongoose and set that equal to require Mongoose because we're going to need that inside this file to create the schema and model and then we're going to create another constant I'm going to call this schema and I'm going to set this equal to Mongoose dot schema and again if you're not sure exactly what I'm doing here and you need a refresher I would advise you to check out my MongoDB tutorial series the link is gonna be down below anyway now we need to create our schema for the book so let's create a constant first of all and we'll call this book schema like so and set it equal to a new schema all right so that thing right here is this thing right it's Mongoose no scheming so inside this scheme and we need to pass through an object and this object is going to describe the different data types and properties we would expect on a book right so remember we have a name property which is going to be a string simple then we have a genre property which is going to be a string and then finally we also have an author ID which is also going to be a string now we also in this schema file defined an ID property right on the books and we also did on the authors but we don't need to do this in this case because MongoDB or M lab is automatically going to create a new ID for each file that we add to the database so we don't need to worry about defining it right here in the schema all right so that's it we've created that schema now so now MongoDB is going to know the kind of data that we're storing right in this particular collection now what we need to do is export a model so we'll say module 2 exports and set that equal to Mongoose dots model so now we're defining a model right which is akin to a collection in MongoDB and the collection name or model name is going to be bulk and we're going to base this model on a particular schema and it's going to be this thing right here the book schema so let's copy that and paste it right here so what we're doing here is we're saying we're making a model right which means a collection if you like a model refers to a collection in a database so we're going to have a collection which is going to be bulks and this collection inside the database is going to have objects inside of it which look like this this schema so that's what we're doing right here then we're exporting that because later on we're going to use this model to interact with our book collection in MongoDB right so let us copy all of this stock because I don't want to retype everything out and paste it inside here these two can stay the same we're going to need the same for the author and will change book right here too author now the different properties inside an author is going to be the name again which is a string we don't need a genre for an author but we do need an age like so and that is going to be a number this time around not a string a number okay so that's this schema for an author now we want to again export a mongoose model this one is going to be called author and it's going to be based on the author schema so we're making two models here one for the author and one for the book and those models represent those two different types of collections in our MongoDB instance so we're going to store them in different collections we use the author model inside our code to interact with the author collection in a database and we use the book model inside our code to interact with the book collection on MongoDB right so we've created both of those two different models right there awesome so then now we have both of these models defined inside our schema the first thing I want to do is get rid of all this junk we don't need the dummy data anymore and inside here we can comment out all these different resolve function code because we're not going to be looking through those arrays anymore we're going to be connecting to MongoDB to get that data so let's just comment all out all of that junk out and then I'm also just going to imports ready the two models we've just created right here so that we're ready to interact with those collections on MongoDB so at the top right here I'm going to say Const book is equal to require then inside we want to say dot dot says to say go up a level go up out of the current folder because we're currently in the schema folder then we want to jump into the models folder then we want to get the book file right book Jas so we've got the book model now we also want the author model which is equal to require again and this time we're going to go up a folder again to jump out at the schema folder then into models then grab the author file all right so now we have these two models already inside our schema file for our graph so what we can do starting in the next tutorial is start to interact with our collections in MongoDB and add data or query data so we'll start that in the very next tutorial