Notes

APIs

  • allow you to connect to other applications
  • stands for Application Programming Interface
    • interface for code/computers to talk to one another
    • from wikipedia: '...is a set of routines, protocols, and tools for building software and applications'
  • Web APIs generally communicate via HTTP --- these are what most people mean when they just say API
  • can have non web APIs for things like connecting to hard drives, video cards, etc.

Web APIs

Data Formats

  • when we use the internet, we make an HTTP request and get HTML back
  • APIs don't respond with HTML because that is the info about the structure of a page --- they respond with data
  • they use simple data formats like XML and JSON

XML

  • Extended Markup Language
  • syntactically similar to HTML, but it doesn't describe presentation like HTML
  • example:
    <person>
  <age>21</age>
  <name>Travis</name>
  <city>Los Angeles</city>
</person>
  • it just describes key/value pairs, can be nested
  • can put whatever you want in the tags

JSON

  • Javascript Object Notation
  • JSON looks exactly like Javascript objects, but everything is a string
  • example:
    {
  "person": {
    "age": "21",
    "name": "Travis",
    "city": "Los Angeles"
  }
}
  • has become much more popular than XML because you are often calling info in javascript --- since JSON is very similar to javascript it is easier to quickly use the data you get back
    • most likely to find XML in older APIs --- very rare in anything new
  • usually shorter than XML

Making API Requests with Node

  • curl is a way to make a request from the terminal
  • in apps for The Web Developer Bootcamp, we will use either the 'axios package' or the 'request package' via Node
  • axios is a promise based package
  • see repo the-web-developer-bootcamp/12_api/axios_lesson for examples with notes

RESTful API (REST API)

  • REST stands for REpresentational State Transfer, which is an architectural style and approach to communications often used in web services development
  • REST is a mapping between HTTP routes and CRUD --- it is a pattern of routes
  • following RESTful route conventions makes code reliable because everyone interacting with it will understand the architecture/patterns it follows --- but it is just a convention, so you can break it if you want

RESTful Routes

example table of the 7 RESTful routes:

Name         url/path         HTTP verb      Mongoose Method           Purpose
                                       
==================================================================================================
INDEX        /dogs            GET            Dog.find()                Display a list of all dogs
--------------------------------------------------------------------------------------------------
NEW          /dogs/new        GET            N/A                       Show new dog form
CREATE       /dogs            POST           Dog.create()              Create a new dog, then
                                                                                redirect
--------------------------------------------------------------------------------------------------
SHOW         /dogs/:id        GET            Dog.findById()            Shows info about one
                                                                                specific dog
--------------------------------------------------------------------------------------------------
EDIT         /dogs/:id/edit   GET            Dog.findById()            Show edit form for one dog
UPDATE       /dogs/:id        PUT            Dog.findByIDAndUpdate()   Update a particular dog, 
                                                                                then redirect
--------------------------------------------------------------------------------------------------
DESTROY      /dogs/:id        DELETE         Dog.findByIdAndRemove()   Delete a particular dog, 
                                                                                then redirect
  • CRUD:
    • Create routes: NEW, CREATE
    • Read routes: INDEX, SHOW
    • Update routes: EDIT, UPDATE
    • Destroy routes: DELETE
  • the 3 routes that redirect are the 3 non-GET requests
  • SHOW/UPDATE/DESTROY and INDEX/CREATE have the same paths/urls, but they are very different because of their different HTTP verbs (GET/PUT/DELETE and GET/POST)
  • see examples in repo: the-web-developer-bootcamp/14_RESTful_blog_app_project

Nested Routes

  • want to add comments to specific dogs --- but can't just add /comments/new and /comments to achieve this because those aren't associated to a dog
  • example table showing the original NEW/CREATE routes and the new NESTED NEW/CREATE routes to add comments: 
Name       url/path                 HTTP verb     Mongoose Method       Purpose
                                       
==================================================================================================
INDEX      /dogs                    GET           Dog.find()            Display a list of all dogs
--------------------------------------------------------------------------------------------------
NEW        /dogs/new                GET           N/A                   Show new dog form
NEW        /dogs/:id/comments/new   GET                                 Show new comment form
CREATE     /dogs                    POST          Dog.create()          Create a new dog, then
                                                                              redirect
CREATE     /dogs/:id/comments       POST          Dog.findById()        Associate with a dog
                                                  Comment.create()      Create a new comment
                                                                        Save them both 
--------------------------------------------------------------------------------------------------
SHOW       /dogs/:id                GET           Dog.findById()        Shows info about one
                                                                              specific dog

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