Node.js Express: API & CLI Apps

Implementing the "GET POST BY ID" RouteImplementing the "GET POST BY ID" Route

We will explore implementing the "GET POST BY ID" route within the postsRoutes.js file. This route fetches and returns a specific post based on its unique identifier (id) provided as part of the URL.


The term 'database' specifically pertains to the posts.json file located in the database folder.

Route Definition

The code below defines the "GET POST BY ID" route using router.get():

  • This route is configured to handle HTTP GET requests.
  • The route path /post/:id includes a parameter :id, which captures the post ID from the URL.

Extracting the Post ID

We extract the post ID from the request parameters using

This line captures the :id value from the URL, making it available for further processing.

Finding the Post in the Database

Next, we search for the post with the matching ID in the database:

  • We use the asynchronous readData function to retrieve data from the JSON file.
  • The find() method is employed to locate a post with a matching ID within the retrieved data.
  • The post variable holds the found post or undefined if no match is found.

Handling the Response

We handle the response based on whether a post was found or not:

  • If no post was found (i.e., post is undefined), we send a 404 response along with an error message, indicating that the requested post was not found.
  • If a post was found, we send the post as the response with a status code of 200 (OK).

Error Handling

We wrap the route code in a try-catch block to handle potential errors during data retrieval or request processing. Any errors that occur are logged to the console for debugging purposes:

Complete code of the postsRoutes.js file at this step

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Section 4. Chapter 6