Mongoose Relationships Lab

Objective: Add embedded comment data and referenced author data to your microblog project.

Each post "has one" author and "has many" comments.

Basic Challenges

Models

Goal: set up or update schema and models in models file

  1. Create a schema and a model for Comment data. The Comment schema should include at least the text of the comment.

  2. Create a schema and a model for Author data. The Author schema should include at least the name of the author.

  3. Update the Post schema to include a list of embedded Comments.

  4. Update the Post schema to include a reference to one Author. If you have an author attribute, replace it.

File connection hints:

  • In the solutions, we add all of the schemas and models to one file and rename it from post.js to models.js.

  • We then update the export line to say module.exports.Post = Post;. (We also add a few export lines.)

  • In the server code, we create a variable called db to hold all of the model module exports:

    var db = require('./models/models');

    This replaces where we directly required './models/posts' and created a Post variable.

  • In the server code, we now access all of our models as attributes of db. Here's an example:

    db.Post.find(function(err, posts){
   console.log(posts);
});

Server Code

Goal: update old routes to accommodate new author format

  1. Update your route to get all blog posts, GET /api/posts. When the server receives a request at this route, it should:

    • find all of the posts from the database

    • populate all of the post's author information

    • send back all the posts as the JSON response

  2. Update your route to create a new blog post, POST /api/posts. When the server receives a request at this route, it should:

    • create and save a new author record

    • create a new post

    • save the new author record's _id as the new post's author

    • save the new post

    • send the new post as the JSON response

Goal: add basic routes for making and reading embedded comments

  1. Make a route to read the comments on one blog post: GET /api/posts/:postid/comments. When the server receives a request at this route, it should:

    • query the database to find the post indicated by the id

    • send the post's comments as the JSON response

  2. Make a route to create a new comment on a blog post: POST /api/posts/:postid/comments. When the server receives a request at this route, it should:

    • query the database to find the post indicated by the id

    • create a new comment record

    • add the new comment to the post's list of embedded comments

    • save the changes to the post

    • send the new comment as the JSON response

Goal: add basic routes for referenced authors

  1. Make a route to get all authors: GET /api/authors. When the server receives a request at this route, it should:

    • query the database to find all authors

    • send the authors as the JSON response

  2. Make a route to create a new author: POST /api/authors. When the server receives a request at this route, it should:

    • make a new author

    • save the new author in the database

    • send the new author as the JSON response

  1. Make a route to assign a specific author to a specific post: PUT /api/posts/:postid/authors/:authorid. When the server receives a request at this route, it should:

    • query the database to find the author (to make sure the id actually matches an author)

    • query the database to find the post

    • update the post to reference the author

    • save the updated post

    • send the updated post as the JSON response

Stretch Challenges: Server Code

  1. Make a route to update a single comment: PUT /api/posts/:postid/comments/:commentid. When the server receives a request at this route, it should:

    • query the database to find the comment indicated by the id

    • update the comment

    • save the comment

    • send the updated comment as a JSON response

  2. Make a route to delete a single comment: DELETE /api/posts/:postid/comments/:commentid. When the server receives a request at this route, it should:

    • query the database to find and the post indicated by the id

    • remove the specified comment from the post's list of embedded Comments

    • query the database to find and remove the comment

    • send the deleted comment as the JSON response (or send a status 200 - your choice)

Stretch Challenges: Client-Side Code

Goal: update old requests to accommodate new author format

When the server sends back post data, the post objects now look like this:

{
    "_id": "55a5835042964888612bc16f",
    "author": {
        "_id": "55a5835042964888612bc16e",
        "name": "Oscar Wilde",
        "__v": 0
    },
    "text": "I can resist everything except temptation.",
    "__v": 0,
    "comments": []
}

We'll need to update the client side code to account for the new format of author -- it's not a string any more; it's an object. In particular, wherever author appears in our template, we'll need to change that to use the author's name.

Goal: Update your view to show all the comments on a post when the post is clicked.

  1. Set up a place in your index.html to display comments. Hint: How about a new column off to one side that shows all the comments for the last clicked post?

    two-column wireframe suggestion

  2. Add a click event listener to tell when a post is clicked. Hint: check out the delete button click event listeners in one of the sample projects.

  3. Update your click event listener to include an AJAX call to GET all the comments for the blog post from your API when a post is clicked.

  4. Use jQuery and Underscore templating to render the comments in the view.

Note: You may notice some bugs (for example, comments don't disappear when you delete their post). Don't worry about them for now.

Goal: display a new comment form when the post is clicked.

  1. Set up a place in your index.html to display the new comment form. Hint: How about over in the comments div?

  2. Update your post click event listener to use jQuery and Underscore templating to render the form in the view.

  3. Add a jQuery submit event handler on the form.

  4. Update your new comment form event handler to POST the data to your API. Hint: which route creates a new comment for a post?

Readings and Submission

Evening Reading

Read Salted Password Hashing - Doing it Right, sections: "What is password hashing?", "How Hashes are Cracked", "Adding Salt".

Submission

Submit the link for your microblog repo on github, along with any comments, in the HW form.