Hypertext Transfer Protocol

# HTTP and REST
            ## Accessing Online Data

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## Request/Response Cycle 
 <dl>
 <dt>HTTP Request</dt>
 <dd>A request for a resource from the browser to a server.</dd>
 <dt>HTTP Response</dt>
 <dd>A response from a server to the browser containing either a requested resource or the result of an operation.</dd>
 </dl>

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## HTTP Terminology
 <dl>
 <dt>Resource</dt>
 <dd>The target of a Request, such as an HTML document, JSON data, image, etc.</dd>
 <dt>Method</dt>
 <dd>A CRUD operation performed on a resource: 
 <ul>
 <li>POST (Create)</li>
 <li>GET (Read)</li>
 <li>PUT (Update)</li>
 <li>DELETE (Delete)</li>
 </ul>
 </dd>
 </dl>

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## Example Request/Response
            1. The browser makes a GET Request for a URL.
            2. The server receives the Request and finds the Resource such as a file, image or data.
            3. The server sends the Resource back as a Response.
            4. The browser receives the Response and might:
                - display a page/image/etc, OR;
                - load JSON data with Javascript.

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## Anatomy of a URL
 See: <a href="https://developer.mozilla.org/en-US/docs/Learn/Common_questions/What_is_a_URL" target="_blank">What is a URL?</a>

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 ### Protocol
 https://example.com/users?name=tony

### Domain
 https://example.com/users?name=tony

### Path (Endpoint)
 https://example.com/users?name=tony

### Query Parameter
 https://example.com/users?name=tony

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## REST APIs
            A standard method of using HTTP to transfer data and/or perform actions between a browser and a server.

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### REST Terminology
 <dl>
 <dt>Endpoint</dt>
 <dd>A fancy name for a URL Path.</dd>
 <dt>Route</dt>
 <dd>An HTTP Method paired with an Endpoint.</dd>
 <dt>Path Segment</dt>
 <dd>The bits of text located between the slashes (<code>/</code>) in a URL Path: /path/to/file</dd>
 <dt>Route Parameter</dt>
 <dd>A variable passed as a Path Segment in a URL.</dd>
 </dl>

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 ### Route Examples (GET)
 Reading Static Files
 <ul class="code no-bullet">
 <li>GET /about-us/index.html</li>
 <li>GET /css/main.css</li>
 <li>GET /images/logo.png</li>
 </ul>

List of articles (JSON data)
 GET /api/articles

Single article (JSON data)
 GET /api/articles/some-title

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### Other Route Examples
 Create a new article:
 POST /api/articles

Update a single article:
 PUT /api/articles/some-title

Delete a single article:
 DELETE /api/articles/some-title

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### API Design & Documentation
 Route Parameters
 
 <ul class="code no-bullet">
 <li>GET /api/users/:id</li>
 <li>PUT /api/users/:id</li>
 <li>GET /api/articles/:slug</li>
 <li>PUT /api/articles/:slug</li>
 </ul>

Sorting
 GET /api/articles?sort=desc

Pagination
 GET /api/articles?page=2&per_page=10

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## Further Reading
 - <a href="https://hevodata.com/learn/crud-vs-rest/" target="_blank">CRUD vs REST Guide: Operations Simplified 101</a>
 - Video: <a href="https://www.youtube.com/watch?v=lsMQRaeKNDk" target="_blank">What is a REST API?</a>