In your Glitch project, in the file manager on the left side of the screen, is there no file called ‘myApp.js’? If not, you could create the file ‘myApp.js’ using ‘+ New File’ and then paste in the following code (don’t put it in the ‘public’ folder, though):
/**********************************************
* 3. FCC Mongo & Mongoose Challenges
* ==================================
***********************************************/
/** # MONGOOSE SETUP #
/* ================== */
/** 1) Install & Set up mongoose */
// Add `mongodb` and `mongoose` to the project's `package.json`. Then require
// `mongoose`. Store your **mLab** database URI in the private `.env` file
// as `MONGO_URI`. Connect to the database using `mongoose.connect(<Your URI>)`
/** # SCHEMAS and MODELS #
/* ====================== */
/** 2) Create a 'Person' Model */
// First of all we need a **Schema**. Each schema maps to a MongoDB collection
// and defines the shape of the documents within that collection. Schemas are
// building block for Models. They can be nested to create complex models,
// but in this case we'll keep things simple. A model allows you to create
// instances of your objects, called **documents**.
// Create a person having this prototype :
// - Person Prototype -
// --------------------
// name : string [required]
// age : number
// favoriteFoods : array of strings (*)
// Use the mongoose basic *schema types*. If you want you can also add more
// fields, use simple validators like `required` or `unique`, and set
// `default` values. See the [mongoose docs](http://mongoosejs.com/docs/guide.html).
// <Your code here >
var Person /* = <Your Model> */
// **Note**: GoMix is a real server, and in real servers interactions with
// the db are placed in handler functions, to be called when some event happens
// (e.g. someone hits an endpoint on your API). We'll follow the same approach
// in these exercises. The `done()` function is a callback that tells us that
// we can proceed after completing an asynchronous operation such as inserting,
// searching, updating or deleting. It's following the Node convention and
// should be called as `done(null, data)` on success, or `done(err)` on error.
// **Warning** - When interacting with remote services, **errors may occur** !
// - Example -
// var someFunc = function(done) {
// ... do something (risky) ...
// if(error) return done(error);
// done(null, result);
// };
/** # [C]RUD part I - CREATE #
/* ========================== */
/** 3) Create and Save a Person */
// Create a `document` instance using the `Person` constructor you build before.
// Pass to the constructor an object having the fields `name`, `age`,
// and `favoriteFoods`. Their types must be conformant to the ones in
// the Person `Schema`. Then call the method `document.save()` on the returned
// document instance, passing to it a callback using the Node convention.
// This is a common pattern, all the **CRUD** methods take a callback
// function like this as the last argument.
// - Example -
// ...
// person.save(function(err, data) {
// ...do your stuff here...
// });
var createAndSavePerson = function(done) {
done(null /*, data*/);
};
/** 4) Create many People with `Model.create()` */
// Sometimes you need to create many Instances of your Models,
// e.g. when seeding a database with initial data. `Model.create()`
// takes an array of objects like [{name: 'John', ...}, {...}, ...],
// as the 1st argument, and saves them all in the db.
// Create many people using `Model.create()`, using the function argument
// 'arrayOfPeople'.
var createManyPeople = function(arrayOfPeople, done) {
done(null/*, data*/);
};
/** # C[R]UD part II - READ #
/* ========================= */
/** 5) Use `Model.find()` */
// Find all the people having a given name, using `Model.find() -> [Person]`
// In its simplest usage, `Model.find()` accepts a **query** document (a JSON
// object ) as the first argument, and returns an **array** of matches.
// It supports an extremely wide range of search options. Check it in the docs.
// Use the function argument `personName` as search key.
var findPeopleByName = function(personName, done) {
done(null/*, data*/);
};
/** 6) Use `Model.findOne()` */
// `Model.findOne()` behaves like `.find()`, but it returns **only one**
// document, even if there are more. It is especially useful
// when searching by properties that you have declared as unique.
// Find just one person which has a certain food in her favorites,
// using `Model.findOne() -> Person`. Use the function
// argument `food` as search key
var findOneByFood = function(food, done) {
done(null/*, data*/);
};
/** 7) Use `Model.findById()` */
// When saving a document, mongodb automatically add the field `_id`,
// and set it to a unique alphanumeric key. Searching by `_id` is an
// extremely frequent operation, so `moongose` provides a dedicated
// method for it. Find the (only!!) person having a certain Id,
// using `Model.findById() -> Person`.
// Use the function argument 'personId' as search key.
var findPersonById = function(personId, done) {
done(null/*, data*/);
};
/** # CR[U]D part III - UPDATE #
/* ============================ */
/** 8) Classic Update : Find, Edit then Save */
// In the good old days this was what you needed to do if you wanted to edit
// a document and be able to use it somehow e.g. sending it back in a server
// response. Mongoose has a dedicated updating method : `Model.update()`,
// which is directly binded to the low-level mongo driver.
// It can bulk edit many documents matching certain criteria, but it doesn't
// pass the edited document to its callback, only a 'status' message.
// Furthermore it makes validation difficult, because it just
// direcly calls the mongodb driver.
// Find a person by Id ( use any of the above methods ) with the parameter
// `personId` as search key. Add "hamburger" to the list of her `favoriteFoods`
// (you can use Array.push()). Then - **inside the find callback** - `.save()`
// the updated `Person`.
// [*] Hint: This may be tricky if in your `Schema` you declared
// `favoriteFoods` as an `Array` without specifying the type (i.e. `[String]`).
// In that case `favoriteFoods` defaults to `Mixed` type, and you have to
// manually mark it as edited using `document.markModified('edited-field')`
// (http://mongoosejs.com/docs/schematypes.html - #Mixed )
var findEditThenSave = function(personId, done) {
var foodToAdd = 'hamburger';
done(null/*, data*/);
};
/** 9) New Update : Use `findOneAndUpdate()` */
// Recent versions of `mongoose` have methods to simplify documents updating.
// Some more advanced features (i.e. pre/post hooks, validation) beahve
// differently with this approach, so the 'Classic' method is still useful in
// many situations. `findByIdAndUpdate()` can be used when searching by Id.
//
// Find a person by `name` and set her age to `20`. Use the function parameter
// `personName` as search key.
//
// Hint: We want you to return the **updated** document. In order to do that
// you need to pass the options document `{ new: true }` as the 3rd argument
// to `findOneAndUpdate()`. By default the method
// passes the unmodified object to its callback.
var findAndUpdate = function(personName, done) {
var ageToSet = 20;
done(null/*, data*/);
};
/** # CRU[D] part IV - DELETE #
/* =========================== */
/** 10) Delete one Person */
// Delete one person by her `_id`. You should use one of the methods
// `findByIdAndRemove()` or `findOneAndRemove()`. They are similar to the
// previous update methods. They pass the removed document to the cb.
// As usual, use the function argument `personId` as search key.
var removeById = function(personId, done) {
done(null/*, data*/);
};
/** 11) Delete many People */
// `Model.remove()` is useful to delete all the documents matching given criteria.
// Delete all the people whose name is "Mary", using `Model.remove()`.
// Pass to it a query ducument with the "name" field set, and of course a callback.
//
// Note: `Model.remove()` doesn't return the removed document, but a document
// containing the outcome of the operation, and the number of items affected.
// Don't forget to pass it to the `done()` callback, since we use it in tests.
var removeManyPeople = function(done) {
var nameToRemove = "Mary";
done(null/*, data*/);
};
/** # C[R]UD part V - More about Queries #
/* ======================================= */
/** 12) Chain Query helpers */
// If you don't pass the `callback` as the last argument to `Model.find()`
// (or to the other similar search methods introduced before), the query is
// not executed, and can even be stored in a variable for later use.
// This kind of object enables you to build up a query using chaining syntax.
// The actual db search is executed when you finally chain
// the method `.exec()`, passing your callback to it.
// There are many query helpers, here we'll use the most 'famous' ones.
// Find people who like "burrito". Sort them alphabetically by name,
// Limit the results to two documents, and hide their age.
// Chain `.find()`, `.sort()`, `.limit()`, `.select()`, and then `.exec()`,
// passing the `done(err, data)` callback to it.
var queryChain = function(done) {
var foodToSearch = "burrito";
done(null/*, data*/);
};
/** **Well Done !!**
/* You completed these challenges, let's go celebrate !
*/
/** # Further Readings... #
/* ======================= */
// If you are eager to learn and want to go deeper, You may look at :
// * Indexes ( very important for query efficiency ),
// * Pre/Post hooks,
// * Validation,
// * Schema Virtuals and Model, Static, and Instance methods,
// * and much more in the [mongoose docs](http://mongoosejs.com/docs/)
//----- **DO NOT EDIT BELOW THIS LINE** ----------------------------------
exports.PersonModel = Person;
exports.createAndSavePerson = createAndSavePerson;
exports.findPeopleByName = findPeopleByName;
exports.findOneByFood = findOneByFood;
exports.findPersonById = findPersonById;
exports.findEditThenSave = findEditThenSave;
exports.findAndUpdate = findAndUpdate;
exports.createManyPeople = createManyPeople;
exports.removeById = removeById;
exports.removeManyPeople = removeManyPeople;
exports.queryChain = queryChain;
If that doesn’t work try doing this exercise again by opening up a new Glitch project from the fCC link on the page titled " Introduction to the MongoDB and Mongoose Challenges"
Maybe even try it in a different browser. Switching from Chrome to Firefox made things different for me just now; in Chrome, the ‘myApp.js’ file was missing and the ‘server.js’ file had only the message ‘This document has been deleted outside of the editor.’ With Firefox, both files were there. I can’t explain why at the moment, though.