View MongoDB Data - Sinatra

Create an application file

At the root level of your project, create a file called app.rb. Paste the following contents into the app.rb file to load the necessary gems and your configuration file:

require 'sinatra'
require 'mongoid'
Mongoid.load!(File.join(File.dirname(__FILE__), 'config', 'mongoid.yml'))

Create a data model

In the app.rb file, create a model called Restaurant to represent data from the sample restaurants collection in the sample_restaurants database:

class Restaurant
  include Mongoid::Document
  field :name, type: String
  field :cuisine, type: String
  field :borough, type: String
end

Generate a view

Create a view to display your data in a specified way by using HTML and Ruby.

At the root level of your project, create a directory called views. Then, create a file called list_restaurants.erb. Paste the following code into the list_restaurants.erb file:

<!DOCTYPE html>
<html>
<head>
    <title>Restaurants List</title>
</head>
<body>
    <h1>Restaurants List</h1>
    <table border="1">
        <tr>
            <th>Name</th>
            <th>Cuisine</th>
            <th>Borough</th>
        </tr>
        <% @restaurants.each do |restaurant| %>
        <tr>
            <td><%= restaurant.name %></td>
            <td><%= restaurant.cuisine %></td>
            <td><%= restaurant.borough %></td>
        </tr>
        <% end %>
    </table>
</body>
</html>

Add a web route

In the app.rb file, add a get route called list_restaurants, as shown in the following code:

get '/list_restaurants' do
    @restaurants = Restaurant
        .where(name: /earth/i)
    erb :list_restaurants
end

This route retrieves Restaurant documents in which the value of the name field contains the string "earth". The route uses the list_restaurants view to render the results.

(Optional) View your results as JSON documents

Instead of generating a view to render your results, you can use the to_json method to display your results in JSON format.

Replace the list_restaurants route in the app.rb file with the following code to return the results as JSON documents:

get '/list_restaurants' do
    restaurants = Restaurant
        .where(name: /earth/i)
    restaurants.to_json
end

Start your Sinatra application

Run the following command from the application root directory to start your Ruby web server:

bundle exec ruby app.rb

After the server starts, it outputs the following message indicating that the application is running on port 4567:

[2024-10-01 12:36:49] INFO  WEBrick 1.8.2
[2024-10-01 12:36:49] INFO  ruby 3.2.5 (2024-07-26) [arm64-darwin23]
== Sinatra (v4.0.0) has taken the stage on 4567 for development with backup from WEBrick
[2024-10-01 12:36:49] INFO  WEBrick::HTTPServer#start: pid=79176 port=4567

View the restaurant data

Open the URL http://localhost:4567/list_restaurants in your web browser. The page shows a list of restaurants and details about each of them:

Note

If you run into issues, ask for help in the MongoDB Stack Overflow tag or the MongoDB Reddit community. You can also submit feedback by using the Rate this page tab on the right side of this page.

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