Add postgres samples

appengine/cloudsql/README.md

@@ -3,8 +3,11 @@
 This sample demonstrates how to use [Google Cloud SQL][sql] (or any other SQL
 server) on [Google App Engine Flexible][flexible].
 
+This sample has instructions for both [MySQL][mysql] and [Postgres][postgres].
+
 ## Setup
 
+### General steps
 Before you can run or deploy the sample, you will need to do the following:
 
 1. In order for some of the commands below to work, you need to enable the
@@ -26,6 +29,10 @@ SDK use the following command:
     where `[YOUR_INSTANCE_NAME]` is the name you chose in step 1 and
     `[YOUR_INSTANCE_ROOT_PASSWORD]` is a password of your choice.
 
+1. Using the [Cloud SQL console][sql_console], select your Cloud SQL instance.
+Then, create a [user][user] (using the button in the *Access Control* > *Users* tab) and a
+[database][database] (using the button in the *Databases* tab).
+
 1. Create and download a [Service Account][service] for your project. You will
 use this service account to connect to your Cloud SQL instance locally.
 
@@ -35,51 +42,60 @@ use this service account to connect to your Cloud SQL instance locally.
 machine:
 
         ./cloud_sql_proxy \
-            -instances=[YOUR_INSTANCE_CONNECTION_NAME]=tcp:3306 \
+            -instances=[YOUR_INSTANCE_CONNECTION_NAME]=tcp:[PORT] \
             -credential_file=PATH_TO_YOUR_SERVICE_ACCOUNT_JSON_FILE
 
     where `[YOUR_INSTANCE_CONNECTION_NAME]` is the connection name of your
     instance on its Overview page in the Google Cloud Platform Console, or use
-    `[YOUR_PROJECT_ID]:[YOUR_REGION]:[YOUR_INSTANCE_NAME]`.
+    `[YOUR_PROJECT_ID]:[YOUR_REGION]:[YOUR_INSTANCE_NAME]`. If you're using
+    MySQL, `[PORT]` will be `3306`; for Postgres, it will be `5432`.
 
-1. Use the MySQL command line tools (or a management tool of your choice) to
-create a [new user][user] and [database][database] for your application:
+1. In a separate terminal, set the `SQL_USER`, `SQL_PASSWORD`, and `SQL_DATABASE` environment
+variables to their respective values. This allows your local app to connect to your Cloud SQL
+instance through the proxy.
 
-        mysql -h 127.0.0.1 -P 3306 -u root -p
-          mysql> create database `YOUR_DATABASE`;
-          mysql> create user 'YOUR_USER'@'%' identified by 'PASSWORD';
-          mysql> grant all on YOUR_DATABASE.* to 'YOUR_USER'@'%';
+    export SQL_USER="..."
+    export SQL_PASSWORD="..."
+    export SQL_DATABASE="..."
 
-1. Set the `MYSQL_USER`, `MYSQL_PASSWORD`, and `MYSQL_DATABASE` environment
-variables (see below). This allows your local app to connect to your Cloud SQL
-instance through the proxy.
+### Choosing a SQL client
+Choose which database connector to use via the `SQL_CLIENT` environment variable.
+
+To use MySQL, set it to `mysql`:
+
+    export SQL_CLIENT="mysql"
+
+To use Postgres, set it to `pg`:
+
+    export SQL_CLIENT="pg"
 
-1. Update the values in in `app.yaml` with your instance configuration.
+### Final setup steps
+1. Update the values in `app.yaml` with your instance configuration.
 
 1. Finally, run `createTables.js` to ensure that the database is properly
 configured and to create the tables needed for the sample.
 
-## Running locally
+### Running locally
 
 Refer to the [top-level README](../README.md) for instructions on running and deploying.
 
 It's recommended to follow the instructions above to run the Cloud SQL proxy.
-You will need to set the following environment variables via your shell before
-running the sample:
+You will need to set the appropriate environment variables (as shown above) and
+run the following commands via your shell to run the sample:
 
-    export MYSQL_USER="YOUR_USER"
-    export MYSQL_PASSWORD="YOUR_PASSWORD"
-    export MYSQL_DATABASE="YOUR_DATABASE"
     npm install
     npm start
 
 [sql]: https://cloud.google.com/sql/
 [flexible]: https://cloud.google.com/appengine
 [gen]: https://cloud.google.com/sql/docs/create-instance
 [console]: https://console.developers.google.com
+[sql_console]: https://console.developers.google.com/sql/instances/
 [sdk]: https://cloud.google.com/sdk
 [service]: https://cloud.google.com/sql/docs/external#createServiceAccount
 [proxy]: https://cloud.google.com/sql/docs/external#install
 [start]: https://cloud.google.com/sql/docs/external#6_start_the_proxy
 [user]: https://cloud.google.com/sql/docs/create-user
 [database]: https://cloud.google.com/sql/docs/create-database
+[mysql]: https://www.mysql.com/downloads/
+[postgres]: https://www.postgresql.org/download/

appengine/cloudsql/app.yaml

@@ -17,11 +17,12 @@ env: flex
 
 # [START env]
 env_variables:
-  MYSQL_USER: YOUR_USER
-  MYSQL_PASSWORD: YOUR_PASSWORD
-  MYSQL_DATABASE: YOUR_DATABASE
+  SQL_USER: YOUR_USER
+  SQL_PASSWORD: YOUR_PASSWORD
+  SQL_DATABASE: YOUR_DATABASE
   # e.g. my-awesome-project:us-central1:my-cloud-sql-instance
   INSTANCE_CONNECTION_NAME: YOUR_INSTANCE_CONNECTION_NAME
+  SQL_CLIENT: YOUR_SQL_CLIENT # either 'pg' or 'mysql' (all lowercase)
 # [END env]
 
 # [START cloudsql_settings]

appengine/cloudsql/createTables.js

@@ -13,71 +13,86 @@
  * limitations under the License.
  */
 
+'use strict';
+
+// Require process, so we can mock environment variables
+const process = require('process');
+
 // [START createTables]
 // [START setup]
-const mysql = require('mysql');
+const Knex = require('knex');
 const prompt = require('prompt');
 // [END setup]
 
 // [START createTable]
-const SQL_STRING = `CREATE TABLE visits (
-  id INT UNSIGNED NOT NULL AUTO_INCREMENT,
-  timestamp DATETIME NULL,
-  userIp VARCHAR(46) NULL,
-  PRIMARY KEY (id)
-);`;
-
 /**
  * Create the "visits" table.
  *
- * @param {object} connection A mysql connection object.
- * @param {function} callback The callback function.
+ * @param {object} knex A Knex client object.
  */
-function createTable (connection, callback) {
-  connection.query(SQL_STRING, callback);
+function createTable (knex) {
+  return knex.schema.createTable('visits', (table) => {
+    table.increments();
+    table.timestamp('timestamp');
+    table.string('userIp');
+  })
+  .then(() => {
+    console.log(`Successfully created 'visits' table.`);
+    return knex;
+  })
+  .catch((err) => {
+    console.error(`Failed to create 'visits' table:`, err);
+    return knex;
+  });
 }
 // [END createTable]
 
 // [START getConnection]
-const FIELDS = ['user', 'password', 'database'];
-
 /**
  * Ask the user for connection configuration and create a new connection.
- *
- * @param {function} callback The callback function.
  */
-function getConnection (callback) {
-  prompt.start();
-  prompt.get(FIELDS, (err, config) => {
-    if (err) {
-      callback(err);
-      return;
-    }
-
-    const user = encodeURIComponent(config.user);
-    const password = encodeURIComponent(config.password);
-    const database = encodeURIComponent(config.database);
+function getConnection () {
+  const FIELDS = ['user', 'password', 'database'];
+  return new Promise((resolve, reject) => {
+    prompt.start();
+    prompt.get(FIELDS, (err, config) => {
+      if (err) {
+        return reject(err);
+      }
 
-    const uri = `mysql://${user}:${password}@127.0.0.1:3306/${database}`;
-    callback(null, mysql.createConnection(uri));
+      // Connect to the database
+      return resolve(Knex({
+        client: process.env.SQL_CLIENT,
+        connection: config
+      }));
+    });
   });
 }
 // [END getConnection]
 
-// [START main]
-getConnection((err, connection) => {
-  if (err) {
-    console.error(err);
-    return;
-  }
-  createTable(connection, (err, result) => {
-    connection.end();
-    if (err) {
-      console.error(err);
-      return;
-    }
-    console.log(result);
-  });
-});
-// [END main]
+exports.main = function () {
+  // [START main]
+  getConnection()
+    .then((knex) => {
+      return createTable(knex);
+    })
+    .then((knex) => {
+      return knex.destroy();
+    })
+    .catch((err, knex) => {
+      console.error(`Failed to create database connection:`, err);
+      if (knex) {
+        knex.destroy();
+      }
+    });
+  // [END main]
+};
 // [END createTables]
+
+// Get type of SQL client to use
+const sqlClient = process.env.SQL_CLIENT;
+if (sqlClient === 'pg' || sqlClient === 'mysql') {
+  exports.main();
+} else {
+  throw new Error(`The SQL_CLIENT environment variable must be set to lowercase 'pg' or 'mysql'.`);
+}

appengine/cloudsql/package.json

@@ -24,7 +24,9 @@
   },
   "dependencies": {
     "express": "4.15.2",
+    "knex": "^0.13.0",
     "mysql": "2.13.0",
+    "pg": "^6.2.3",
     "prompt": "1.0.0"
   },
   "devDependencies": {
@@ -35,19 +37,18 @@
     "test": {
       "app": {
         "requiredEnvVars": [
-          "MYSQL_USER",
-          "MYSQL_PASSWORD",
-          "MYSQL_DATABASE",
-          "YOUR_INSTANCE_CONNECTION_NAME"
+          "SQL_CLIENT",
+          "SQL_USER",
+          "SQL_PASSWORD",
+          "SQL_DATABASE",
+          "INSTANCE_CONNECTION_NAME"
         ],
         "msg": "Last 10 visits:",
-        "args": ["server.js"]
-      },
-      "deploy": {
-        "substitutions": "YOUR_USER=$MYSQL_USER,YOUR_PASSWORD=$MYSQL_PASSWORD,YOUR_DATABASE=$MYSQL_DATABASE,YOUR_INSTANCE_CONNECTION_NAME=$INSTANCE_CONNECTION_NAME"
+        "substitutions": "YOUR_SQL_CLIENT=$SQL_CLIENT,YOUR_USER=$SQL_USER,YOUR_PASSWORD=$SQL_PASSWORD,YOUR_DATABASE=$SQL_DATABASE,YOUR_INSTANCE_CONNECTION_NAME=$INSTANCE_CONNECTION_NAME",
+        "args": [
+          "server.js"
+        ]
       }
-    },
-    "requiresKeyFile": true,
-    "requiresProjectId": true
+    }
   }
 }