Using Cloud SQL for PostgreSQL with PHP

This part of the PHP Bookshelf tutorial shows how to create, read, update, and delete structured data in Google Cloud SQL for PostgreSQL.

This page is part of a multi-page tutorial. To start from the beginning and see instructions for setting up, go to PHP Bookshelf App.

Creating a Cloud SQL instance and database

Install the SQL proxy

Download and install the Cloud SQL Proxy. The Cloud SQL Proxy is used to connect to your Cloud SQL instance when running locally.

Linux 64-bit

  1. Download the proxy:
    wget https://dl.google.com/cloudsql/cloud_sql_proxy.linux.amd64 -O cloud_sql_proxy
    
  2. Make the proxy executable:
    chmod +x cloud_sql_proxy
    

Linux 32-bit

  1. Download the proxy:
    wget https://dl.google.com/cloudsql/cloud_sql_proxy.linux.386 -O cloud_sql_proxy
    
  2. Make the proxy executable:
    chmod +x cloud_sql_proxy
    

OS X 64-bit

  1. Download the proxy:
    curl -o cloud_sql_proxy https://dl.google.com/cloudsql/cloud_sql_proxy.darwin.amd64
    
  2. Make the proxy executable:
    chmod +x cloud_sql_proxy
    

OS X 32-bit

  1. Download the proxy:
    curl -o cloud_sql_proxy https://dl.google.com/cloudsql/cloud_sql_proxy.darwin.386
    
  2. Make the proxy executable:
    chmod +x cloud_sql_proxy
    

Windows 64-bit

Right-click https://dl.google.com/cloudsql/cloud_sql_proxy_x64.exe and select "Save link as..." to download the proxy, renaming it to cloud_sql_proxy.exe.

Windows 32-bit

Right-click https://dl.google.com/cloudsql/cloud_sql_proxy_x86.exe and select "Save link as..." to download the proxy, renaming it to cloud_sql_proxy.exe.
If your operating system is not included here, you can also compile the proxy from source.

Create a Cloud SQL instance

  1. Create a Cloud SQL for PostgreSQL instance.

    Name the instance library or similar. It can take a few minutes for the instance to be ready. After the instance is ready, it should be visible in the instances list.

  2. Now use the Cloud SDK from command line to run the following command. Copy the value shown for connectionName for the next step.
    gcloud sql instances describe [YOUR_INSTANCE_NAME]

    The connectionName value is in the format [PROJECT_NAME]:[REGION_NAME]:[INSTANCE_NAME].

Initialize your Cloud SQL instance

  1. Start the Cloud SQL Proxy using the connectionName from the previous step.

    Linux/Mac OS X

    ./cloud_sql_proxy -instances="[YOUR_INSTANCE_CONNECTION_NAME]"=tcp:5432

    Windows

    cloud_sql_proxy.exe -instances="[YOUR_INSTANCE_CONNECTION_NAME]"=tcp:5432

    Replace [YOUR_INSTANCE_CONNECTION_NAME] with the value of connectionName that you recorded in the previous step.

    This step establishes a connection from your local computer to your Cloud SQL instance for local testing purposes. Keep the Cloud SQL Proxy running the entire time you test your application locally.

  2. Next you create a new Cloud SQL user and database.

    CONSOLE

    1. Create a new database using the GCP Console for your Cloud SQL instance library. For example, you can use the name bookshelf.
    2. Create a new user using the GCP Console for your Cloud SQL instance library.

    POSTGRES CLIENT

    1. In a separate command-line tab, install the Postgres client.
      sudo apt-get install postgresql
      
    2. Use the Postgres client or similar program to connect to your instance. When prompted, use the root password you configured.
      psql --host 127.0.0.1 --user postgres --password
      
    3. Create the required databases, users, and access permissions in your Cloud SQL database using the commands below. Replace [POSTGRES_USER] and [POSTGRES_PASSWORD] with your desired username and password.
      CREATE DATABASE bookshelf;
      CREATE USER [POSTGRES_USER] WITH PASSWORD '[POSTGRES_PASSWORD]';
      GRANT ALL PRIVILEGES ON DATABASE bookshelf TO [POSTGRES_USER];
      GRANT ALL PRIVILEGES ON ALL TABLES IN SCHEMA public TO [POSTGRES_USER];
      

Configuring settings

  1. Go to the getting-started-php/2-structured-data directory, and copy the settings.yml.dist file:

    cp config/settings.yml.dist config/settings.yml
    
  2. Open config/settings.yml for editing.

  3. Replace YOUR_PROJECT_ID with your project ID.

  4. Set the value of bookshelf_backend to postgres.

  5. Set the values of cloudsql_connection_name, cloudsql_database_name, cloudsql_user, cloudsql_password, and cloudsql_port to the appropriate values for your Cloud SQL instance. Since you are using postgres, you should use port 5432. For example:

    cloudsql_connection_name: your_project_name:your_region:your_instance
    cloudsql_database_name: bookshelf
    cloudsql_user: phpapp
    cloudsql_password: password
    cloudsql_port: 5432
    
  6. Save and close settings.yml.

You also need to update app.yaml before deploying:

  1. Open app.yaml for editing.

  2. Uncomment the beta_settings and cloud_sql_instances lines. Set the value of cloud_sql_instances to the value you used for cloudsql_connection_name in config/settings.yml. It should be in the format your_project_name:your_region:your_instance.

  3. Save and close app.yaml.

Installing dependencies

In the 2-structured-data directory, enter this command.

composer install

Running the app on your local machine

  1. Start a local web server:

    php -S localhost:8000 -t web
    
  2. In your web browser, enter this address.

    http://localhost:8000

Now you can browse the app's web pages and add, edit, and delete books.

Deploying the app to the App Engine flexible environment

  1. Deploy the sample app:

    gcloud app deploy
    
  2. In your web browser, enter this address. Replace [YOUR_PROJECT_ID] with your project ID:

    https://[YOUR_PROJECT_ID].appspot.com
    

    If you update your app, you can deploy the updated version by entering the same command you used to deploy the app the first time. The new deployment creates a new version of your app and promotes it to the default version. The older versions of your app remain, as do their associated VM instances. Be aware that all of these app versions and VM instances are billable resources.

    You can reduce costs by deleting the non-default versions of your app.

    To delete an app version:

    1. In the Cloud Platform Console, go to the App Engine Versions page.

      Go to the Versions page

    2. Click the checkbox next to the non-default app version you want to delete.
    3. Click the Delete button at the top of the page to delete the app version.

    For complete information about cleaning up billable resources, see the Cleaning up section in the final step of this tutorial.

    Application structure

    This diagram shows the app's components and how they fit together.

    Bookshelf app deployment process and structure

    Understanding the code

    Previously, you edited settings.yml and set the value of bookshelf_backend to postgres. This tells the app to load the Sql class, which is defined in src/DataModel/Sql.php. The Sql class wraps the PDO API, and is responsible for storing books in your Cloud SQL database.

    This code in controllers.php defines and registers a handler for the GET '/books' route. The $model variable is an instance of the Sql class. The $model->listBooks method returns an array that contains an array of books and a cursor. Then the Twig template engine renders the list of books according to the list.html.twig template:

    $app->get('/books/', function (Request $request) use ($app) {
        /** @var DataModelInterface $model */
        $model = $app['bookshelf.model'];
        /** @var Twig_Environment $twig */
        $twig = $app['twig'];
        $token = $request->query->get('page_token');
        $bookList = $model->listBooks($app['bookshelf.page_size'], $token);
    
        return $twig->render('list.html.twig', array(
            'books' => $bookList['books'],
            'next_page_token' => $bookList['cursor'],
        ));
    });

    Here is the Twig template for listing books that are retrieved from the Cloud SQL database. The template receives an array variable named books. For each book in the array, it displays the title and author. The template also receives a next_page_token variable that determines whether the More button is displayed.

    {% for book in books %}
    <div class="media">
      <a href="/books/{{book.id}}">
        <div class="media-left">
          <img src="http://placekitten.com/g/128/192">
        </div>
        <div class="media-body">
          <h4>{{book.title}}</h4>
          <p>{{book.author}}</p>
        </div>
      </a>
    </div>
    {% else %}
    <p>No books found</p>
    {% endfor %}

    This code defines and registers a handler for the GET '/books/{id}' route, where {id} is the ID of an individual book. The handler calls the $model->read method to get the specified book from Cloud SQL. The Twig template engine renders the book according to the view.html.twig template:

    $app->get('/books/{id}', function ($id) use ($app) {
        /** @var DataModelInterface $model */
        $model = $app['bookshelf.model'];
        $book = $model->read($id);
        if (!$book) {
            return new Response('', Response::HTTP_NOT_FOUND);
        }
        /** @var Twig_Environment $twig */
        $twig = $app['twig'];
    
        return $twig->render('view.html.twig', array('book' => $book));
    });

    The view.html.twig template receives a variable named book, and displays the book's title, publication date, author, and description.

    <div class="media">
      <div class="media-body">
        <h4 class="book-title">
          {{book.title}}
          <small>{{book.published_date}}</small>
        </h4>
        <h5 class="book-author">By {{book.author|default('Unknown', True)}}</h5>
        <p class="book-description">{{book.description}}</p>
      </div>
    </div>

    When the user clicks Add book, the handler for GET /books/add displays a form for entering the title, author and other information about a book. When the user clicks Save, the handler for POST /books/add gets the new book from the request, and calls $model->create to store the book in Cloud SQL:

    $app->get('/books/add', function () use ($app) {
        /** @var Twig_Environment $twig */
        $twig = $app['twig'];
    
        return $twig->render('form.html.twig', array(
            'action' => 'Add',
            'book' => array(),
        ));
    });
    
    $app->post('/books/add', function (Request $request) use ($app) {
        /** @var DataModelInterface $model */
        $model = $app['bookshelf.model'];
        $book = $request->request->all();
        $id = $model->create($book);
    
        return $app->redirect("/books/$id");
    });

    Here's the template for the book entry form:

    {% extends "base.html.twig" %}
    
    {% block content %}
    <h3>{{action}} book</h3>
    
    <form method="POST" enctype="multipart/form-data">
    
      <div class="form-group">
        <label for="title">Title</label>
        <input type="text" name="title" id="title" value="{{book.title}}" class="form-control"/>
      </div>
    
      <div class="form-group">
        <label for="author">Author</label>
        <input type="text" name="author" id="author" value="{{book.author}}" class="form-control"/>
      </div>
    
      <div class="form-group">
        <label for="published_date">Date Published</label>
        <input type="text" name="published_date" id="published_date" value="{{book.published_date}}" class="form-control"/>
      </div>
    
      <div class="form-group">
        <label for="description">Description</label>
        <textarea name="description" id="description" class="form-control">{{book.description}}</textarea>
      </div>
    
      <button id="submit" type="submit" class="btn btn-success">Save</button>
    </form>
    
    {% endblock %}

    The sample code includes additional handlers for editing and deleting individual books:

    $app->get('/books/{id}/edit', function ($id) use ($app) {
        /** @var DataModelInterface $model */
        $model = $app['bookshelf.model'];
        $book = $model->read($id);
        if (!$book) {
            return new Response('', Response::HTTP_NOT_FOUND);
        }
        /** @var Twig_Environment $twig */
        $twig = $app['twig'];
    
        return $twig->render('form.html.twig', array(
            'action' => 'Edit',
            'book' => $book,
        ));
    });
    
    $app->post('/books/{id}/edit', function (Request $request, $id) use ($app) {
        $book = $request->request->all();
        $book['id'] = $id;
        /** @var DataModelInterface $model */
        $model = $app['bookshelf.model'];
        if (!$model->read($id)) {
            return new Response('', Response::HTTP_NOT_FOUND);
        }
        if ($model->update($book)) {
            return $app->redirect("/books/$id");
        }
    
        return new Response('Could not update book');
    });
    $app->post('/books/{id}/delete', function ($id) use ($app) {
        /** @var DataModelInterface $model */
        $model = $app['bookshelf.model'];
        $book = $model->read($id);
        if ($book) {
            $model->delete($id);
    
            return $app->redirect('/books/', Response::HTTP_SEE_OTHER);
        }
    
        return new Response('', Response::HTTP_NOT_FOUND);
    });

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