Hatchways Back-end Assessment

Data Source

You will be building an API that requires you to fetch data from this API:

• Request:

  Route: [https://api.hatchways.io/assessment/blog/posts] Method: GET
  Query Parameters:

  Field	Type	Description
  Tag	String(Required)	The tag associated with the blog post.

Notice that the parameter is a query parameter - you can read more about query parameters here. An example of sending the tag parameter is https://api.hatchways.io/assessment/blog/posts?tag=tech. Our API can only filter one tag at a time - notice that the field “tag” is singular and not plural. It will return a JSON object with an array of blog posts. An example response is:

{
    "posts": [
    {
        "id": 1,
        "author": "Rylee Paul",
        "authorId": 9,
        "likes": 960,
        "popularity": 0.13,
        "reads": 50361,
        "tags": [ "tech", "health" ]
    }, ...

API Requirements

You need the following routes in your API:

Route 1:

• Request:

  Route: [/api/ping]
  Method: GET
  Query Parameters:
  Response body (JSON):

      {
          "success": true
      }
  

    Response status code: 200
  

Route 2:

• Request:

  Route: [/api/posts]
  Method: GET
  Query Parameters:
  

  | Field     	| Type             	| Description                                                                                                    	| Default 	| Example      	|
  |-----------	|------------------	|----------------------------------------------------------------------------------------------------------------	|---------	|--------------	|
  | tags      	| String(Required) 	| The tag associated with the blog post.                                                                         	| N/A     	| science,tech 	|
  | sortBy    	| String(optional) 	| The field to sort the posts by. The acceptable fields are:<br>● id<br>● reads<br>● likes<br>● popularity 	| id      	| popularity   	|
  | direction 	| String(optional) 	| The direction for sorting. The acceptable fields are:<br>● desc<br>● asc                                 	| asc     	| asc          	|
  

• Successful Response: The API response will be a list of all the blog posts that have at least one tag specified in the tags parameter. The sortBy parameter specifies which field should be used to sort the returned results. This is an optional parameter, with a default value of id. The direction parameter specifies if the results should be returned in ascending order (if the value is "asc") or descending order (if the value is "desc"). The default value of the direction parameter is asc.

  Here is how the response should look:

  Here is how the response should look: Response body (JSON):

  {
      "posts": [
      {
          "id": 1,
          "author": "Rylee Paul",
          "authorId": 9,
          "likes": 960,
          "popularity": 0.13,
          "reads": 50361,
          "tags": [ "tech", "health" ]
      },
      ...
      ]
  }
  

  Response status code: 200

• Error Responses: If tags parameter is not present: Response body (JSON):

  {
      "error": "Tags parameter is required"
  }
  

  Response status code: 400 If a sortBy or direction are invalid values, specify an error like below: Response body (JSON):

  {
      "error": "sortBy parameter is invalid"
  }
  

  Response status code: 400

Here is what you will need to do to complete this task:

• For every tag specified in the tags parameter, fetch the posts with that tag using the Hatchways API (make a separate API request for every tag specified)
• Combine all the results from the API requests above and remove all the repeated posts (try to be efficient when doing this)
• You will get a better score on our assessment if you can make concurrent requests to the API (making the requests in parallel) (we understand that this job is easier in some languages vs. others)

We have provided an API with the correct solution. This should only be used to verify your results. Do not call this API in your application. Here it is in action: [https://api.hatchways.io/assessment/solution/posts?tags=history,tech&sortBy=likes&d irection=desc]

Step 3

An important part of development is testing. In this step, we want to see tests written for your routes. Do not use the solutions API route to perform testing in this step. Think about the different ways to test the app, and the best way to get good coverage.

Step 4 (Bonus!)

Making API calls to other servers can be expensive. How can you reduce the number of calls you make to a server? You can cache the results of an API call on your server. Try to implement a server side cache to our API. Two tips are

1. keep it simple
2. feel free to use existing libraries/frameworks.