Ada-C13 / ada-pets-node

Ada Pets Node

At a Glance

• Individual, stage 1 project.
• Due before class, Friday, April 10
• Submit this project with a PR

Learning Goals

• Reading and understanding existing JavaScript code
• Using axios to read data from an API in JavaScript
• Parsing through an API response in JavaScript and extracting desired information
• Using axios to write data to an API in JavaScript

Introduction

Ada Lovelace is starting a pet rescue service advertising pets in need of rescue via an API and is building a CLI app. This app should load the list of pets automatically and present a menu with options. The user should be able to list all pets, select a pet and see details, add new pets and remove a pet from the App once adopted.

She's managed to figure out the CLI parts on her own but needs your help with the API requests.

Setup

1. Fork and clone this repository
2. Run npm install to install dependencies
3. Run the app with node src/main.js

Layout

You will be adding your code to src/adaPets.js. All of the functions you need to implement are currently there, just with empty bodies.

There are two other files that we've provided that you won't need to change src/main.js and src/result.js. They are worth taking a quick look at but don't worry too much if you don't understand them fully.

• src/main.js is the actual driver code for the CLI app. If you want to manually test your code you can use this.
• src/result.js is the library we've written to handle results and errors for this app. It provides three functions, two of which you will use and one of which you're going to see in the tests. Every helper function should make sure to call setResult or setError before each return. What we pass into setResult and setError will be detailed per wave.
  • setResult call this function to set the result of your function. We use this because Axios is asynchronous.
  • setError call this function to indicate an error in your function. Again, we use this because Axios is asynchronous.
  • If it takes too long for your code to produce a result (like say because you haven't written it yet) it will time out.

Note: Because Axios is asynchronous we will need to use setResult instead of returning results and setError instead of throwing errors.

Testing Requirements

There are tests for each of the waves in the test/ directory, there is one file per wave. For example you can run the Wave 1 tests with jest test/wave1.test.js.

Use the tests to help you verify each wave's completion. We expect by project submission that all tests will pass.

Wave 0: Familiarize Yourself with the Pets API

We will be using a simulated API for this exercise called json-server. This node package will take a JSON file and use it to generate a RESTful API.

You can look at the package.json file and see this section

"scripts": {
    "test": "jest",
    "server": "json-server --watch pets.json"
  },

This means you can start the API server by typing $ npm run server. This will start the API on port 3000.

You can preview it by going to http://localhost:3000/pets.

In Postman, try to make a few API calls to verify how it works including:

• Listing all the pets
• Listing a single pet by ID
• Adding a pet
• Updating a Pet

Notice how the pets.json file changes.

Answer the following questions to guide through familiarizing yourself with the API:

Remember, all requests that we make have a verb and a path.

1. What is the verb and path of the request to get a list of pets from this API?
2. The response of this request should be a list of pets. What kind of data structure is the list of pets? What is the status code of this request? Test it with Postman.
3. What is the verb and path of the request to get the details of a single pet from this API?
4. What are the query parameters of this request?
5. Test with Postman:
   • What kind of data structure is the details of a single, valid pet? What is the status code of this request?
   • What do we get back if we give an invalid pet id? What is the status code of this request?
6. What is the verb and path of the request to create a new pet using this API?
7. What are the parameters we can pass into this request? Which parameters are required? Which are optional?
8. When a pet is successfully created, we get back a response. What is the data structure of this response? What is the status code?
9. After we create a pet, we can verify that the pet was created from the response. We can also verify that the pet was created and added to the list of pets another way. What else can we do?

Important Provided Functions

setResult

This function is used to indicate that your function has actually produced a meaningful result. (This is necessary because of the asynchronous nature of JavaScript input/output.)

If you return a value instead of calling setResult (or setError) then your tests will time out (fail because you took too long to produce a result).

setError

This function is used to indicate that your function has produced an error. (Again, this is necessary because of the asynchronous nature of JavaScript input/output.)

You should use this function instead of throwing an error from your functions.

A note on tests: Many of the tests that expect you to set an error will validate not only that your code produced an error but also that it had an error message that included specific words using regular expressions.

Wave 1: List Pets

Before we start doing things like looking at individual pets we want to be able to get a list of all of the pets.

To do this fill out the listPets function. This will need to make a call to the Pets API and should setResult a list of objects containing (at least) the pet's id and name and should call setError with an error message if the request fails.

You can run the Wave 1 tests with jest test/wave1.test.js. Once these are passing move on to Wave 2.

These tests use a mocking library to do what we used VCR to do in Ruby. In each test you'll see a mock.onGet or mock.onPost to set up what should happen for that particular test before the actual assertions.

Function to complete

• listPets
  • setResult should be passed the array of pets.
  • setError should be passed an error message. (You may need to write this message.)

Wave 2: Details

We now want to be able to look at individual pets. Like in Slack CLI we're going to want to select a given pet before we ask for details on one. To do this we're going to fill out a few functions that we're creating within a closure. There is a provided function selectPet that will prompt you for a pet's id and save it.

To do this you will need to fill out the petDetails function. This will need to make a call to the Pets API and should setResult and object with details for the pet and should call setError with an error message if the request fails.

You can run the Wave 2 tests with jest test/wave2.test.js. Once these are passing move on to Wave 3.

Function to complete

• showDetails
  • setResult should be passed the Object that represents the pet.
  • setError should be passed an error message. (You may need to write this message.)

Wave 3: Remove Pet

Once a pet is adopted we don't still want to show it on the list. (We don't want people fighting over the same pet after all 😉.)

To do this fill out the removePet function. This will need to call to the Pets API to remove the pet. This should setResult with a success message if this works and should call setError with an error message if the request fails.

You can run the Wave 3 tests with jest test/wave3.test.js. Once these are passing move on to Wave 4.

Function to complete

• removePet
  • setResult should be passed a success message. (You may need to write this message.)
  • setError should be passed an error message. (You may need to write this message.)

Wave 4: Add a Pet

Sometimes we'll have new pets that want to be adopted.

To do this fill out the addPet function. This will need to call the Pets API to add the pet. This should setResult with a success message if this works and should call setError with an error message if the request fails.

You can run the Wave 4 tests with jest test/wave4.test.js. Once these are passing you're done! 🎉

Function to complete

• addPet
  • setResult should be passed the new pet (from the API).
  • setError should be passed an error message. (You may need to write this message.)