Integrate Azure Database for PostgreSQL with Service Connector

For .NET, there's not a plugin or library to support passwordless connections. You can get an access token for the managed identity or service principal using client library like Azure.Identity. Then you can use the access token as the password to connect to the database. When using the code below, uncomment the part of the code snippet for the authentication type you want to use.

using Azure.Identity;
using Azure.Core;
using Npgsql;

// Uncomment the following lines corresponding to the authentication type you want to use.
// For system-assigned identity.
// var sqlServerTokenProvider = new DefaultAzureCredential();

// For user-assigned identity.
// var sqlServerTokenProvider = new DefaultAzureCredential(
//     new DefaultAzureCredentialOptions
//     {
//         ManagedIdentityClientId = Environment.GetEnvironmentVariable("AZURE_POSTGRESQL_CLIENTID");
//     }
// );

// For service principal.
// var tenantId = Environment.GetEnvironmentVariable("AZURE_POSTGRESQL_TENANTID");
// var clientId = Environment.GetEnvironmentVariable("AZURE_POSTGRESQL_CLIENTID");
// var clientSecret = Environment.GetEnvironmentVariable("AZURE_POSTGRESQL_CLIENTSECRET");
// var sqlServerTokenProvider = new ClientSecretCredential(tenantId, clientId, clientSecret);

// Acquire the access token. 
AccessToken accessToken = await sqlServerTokenProvider.GetTokenAsync(
    new TokenRequestContext(scopes: new string[]
    {
        "https://ossrdbms-aad.database.windows.net/.default"
    }));

// Combine the token with the connection string from the environment variables provided by Service Connector.
string connectionString =
    $"{Environment.GetEnvironmentVariable("AZURE_POSTGRESQL_CONNECTIONSTRING")};Password={accessToken.Token}";

// Establish the connection.
using (var connection = new NpgsqlConnection(connectionString))
{
    Console.WriteLine("Opening connection using access token...");
    connection.Open();
}

1. Add the following dependencies in your pom.xml file:

   <dependency>
       <groupId>org.postgresql</groupId>
       <artifactId>postgresql</artifactId>
       <version>42.3.6</version>
   </dependency>
   <dependency>
       <groupId>com.azure</groupId>
       <artifactId>azure-identity-extensions</artifactId>
       <version>1.1.5</version>
   </dependency>
   

2. Get the connection string from environment variables and add the plugin name to connect to the database:

   import java.sql.*;
   
   String url = System.getenv("AZURE_POSTGRESQL_CONNECTIONSTRING");
   String pluginName = "com.Azure.identity.extensions.jdbc.postgresql.AzurePostgresqlAuthenticationPlugin";  
   Connection connection = DriverManager.getConnection(url + "&authenticationPluginClassName=" + pluginName);
   

For more information, see the following resources:

• Tutorial: Connect to PostgreSQL Database from a Java Quarkus Container App without secrets using a managed identity
• Tutorial: Connect to a PostgreSQL Database from Java Tomcat App Service without secrets using a managed identity
• Quickstart: Use Java and JDBC with Azure Database for PostgreSQL Flexible Server
• Migrate an application to use passwordless connections with Azure Database for PostgreSQL

For a Spring application, if you create a connection with option --client-type springboot, Service Connector sets the properties spring.datasource.azure.passwordless-enabled, spring.datasource.url, and spring.datasource.username to Azure Spring Apps.

Update your application following the tutorial Bind an Azure Database for PostgreSQL to your application in Azure Spring Apps. Remember to remove the spring.datasource.password configuration property if it was set before and add the correct dependencies to your Spring application.

For more tutorials, see Use Spring Data JDBC with Azure Database for PostgreSQL and Tutorial: Deploy a Spring application to Azure Spring Apps with a passwordless connection to an Azure database.

1. Install dependencies.

   pip install azure-identity
   pip install psycopg2-binary
   pip freeze > requirements.txt # Save the dependencies to a file
   

2. Get access token using azure-identity library and use the token as password. Get connection information from the environment variables added by Service Connector. When using the code below, uncomment the part of the code snippet for the authentication type you want to use.

   from azure.identity import DefaultAzureCredential
   import psycopg2
   
   # Uncomment the following lines corresponding to the authentication type you want to use.
   # For system-assigned identity.
   # cred = DefaultAzureCredential()
   
   # For user-assigned identity.
   # managed_identity_client_id = os.getenv('AZURE_POSTGRESQL_CLIENTID')
   # cred = ManagedIdentityCredential(client_id=managed_identity_client_id)   
   
   # For service principal.
   # tenant_id = os.getenv('AZURE_POSTGRESQL_TENANTID')
   # client_id = os.getenv('AZURE_POSTGRESQL_CLIENTID')
   # client_secret = os.getenv('AZURE_POSTGRESQL_CLIENTSECRET')
   # cred = ClientSecretCredential(tenant_id=tenant_id, client_id=client_id, client_secret=client_secret)
   
   # Acquire the access token
   accessToken = cred.get_token('https://ossrdbms-aad.database.windows.net/.default')
   
   # Combine the token with the connection string from the environment variables added by Service Connector to establish the connection.
   conn_string = os.getenv('AZURE_POSTGRESQL_CONNECTIONSTRING')
   conn = psycopg2.connect(conn_string + ' password=' + accessToken.token) 
   

1. Install dependencies.

   pip install azure-identity
   

2. Get access token using azure-identity library using environment variables added by Service Connector. When using the code below, uncomment the part of the code snippet for the authentication type you want to use.

   from azure.identity import DefaultAzureCredential
   import psycopg2
   
   # Uncomment the following lines corresponding to the authentication type you want to use.
   # For system-assigned identity.
   # credential = DefaultAzureCredential()
   
   # For user-assigned identity.
   # managed_identity_client_id = os.getenv('AZURE_POSTGRESQL_CLIENTID')
   # cred = ManagedIdentityCredential(client_id=managed_identity_client_id)    
   
   # For service principal.
   # tenant_id = os.getenv('AZURE_POSTGRESQL_TENANTID')
   # client_id = os.getenv('AZURE_POSTGRESQL_CLIENTID')
   # client_secret = os.getenv('AZURE_POSTGRESQL_CLIENTSECRET')
   # cred = ClientSecretCredential(tenant_id=tenant_id, client_id=client_id, client_secret=client_secret)
   
   # Acquire the access token.
   accessToken = cred.get_token('https://ossrdbms-aad.database.windows.net/.default')
   

3. In setting file, get Azure PostgreSQL database information from environment variables added by Service Connector service. Use accessToken acquired in previous step to access the database.

   # In your setting file, eg. settings.py
   host = os.getenv('AZURE_POSTGRESQL_HOST')
   user = os.getenv('AZURE_POSTGRESQL_USER')
   password = accessToken.token # this is accessToken acquired from above step.
   database = os.getenv('AZURE_POSTGRESQL_NAME')
   
   DATABASES = {
       'default': {
           'ENGINE': 'django.db.backends.postgresql_psycopg2',
           'NAME': database,
           'USER': user,
           'PASSWORD': password,
           'HOST': host,
           'PORT': '5432',  # Port is 5432 by default 
           'OPTIONS': {'sslmode': 'require'},
       }
   }
   

1. Install dependencies.

   go get github.com/lib/pq
   go get "github.com/Azure/azure-sdk-for-go/sdk/azidentity"
   go get "github.com/Azure/azure-sdk-for-go/sdk/azcore"
   

2. In code, get access token using azidentity, then use it as password to connect to Azure PostgreSQL along with connection information provided by Service Connector. When using the code below, uncomment the part of the code snippet for the authentication type you want to use.

   import (
   "database/sql"
   "fmt"
   "os"
   
   "context"
   
   "github.com/Azure/azure-sdk-for-go/sdk/azcore/policy"
   "github.com/Azure/azure-sdk-for-go/sdk/azidentity"
   
    _ "github.com/lib/pq"
   )    
   
   // Uncomment the following lines corresponding to the authentication type you want to use.
   // For system-assigned identity.
   // cred, err := azidentity.NewDefaultAzureCredential(nil)
   
   // For user-assigned identity.
   // clientid := os.Getenv("AZURE_POSTGRESQL_CLIENTID")
   // azidentity.ManagedIdentityCredentialOptions.ID := clientid
   // options := &azidentity.ManagedIdentityCredentialOptions{ID: clientid}
   // cred, err := azidentity.NewManagedIdentityCredential(options)
   
   // For service principal.
   // clientid := os.Getenv("AZURE_POSTGRESQL_CLIENTID")
   // tenantid := os.Getenv("AZURE_POSTGRESQL_TENANTID")
   // clientsecret := os.Getenv("AZURE_POSTGRESQL_CLIENTSECRET")
   // cred, err := azidentity.NewClientSecretCredential(tenantid, clientid, clientsecret, &azidentity.ClientSecretCredentialOptions{})
   
   if err != nil {
       // error handling
   }
   
   // Acquire the access token
   ctx, cancel := context.WithTimeout(context.Background(), 30*time.Second)
   token, err := cred.GetToken(ctx, policy.TokenRequestOptions{
       Scopes: []string("https://ossrdbms-aad.database.windows.net/.default"),
   })
   
   // Combine the token with the connection string from the environment variables added by Service Connector to establish the connection.
   connectionString := os.Getenv("AZURE_POSTGRESQL_CONNECTIONSTRING") + " password=" + token.Token
   
   conn, err := sql.Open("postgres", connectionString)
    if err != nil {
    	panic(err)
    }
   
    conn.Close()
   

1. Install dependencies.

   npm install --save @azure/identity
   npm install --save pg
   

2. In code, get the access token using @azure/identity and PostgreSQL connection information from environment variables added by Service Connector service. Combine them to establish the connection. When using the code below, uncomment the part of the code snippet for the authentication type you want to use.

   import { DefaultAzureCredential, ClientSecretCredential } from "@azure/identity";
   const { Client } = require('pg');
   
   // Uncomment the following lines corresponding to the authentication type you want to use.  
   // For system-assigned identity.
   // const credential = new DefaultAzureCredential();
   
   // For user-assigned identity.
   // const clientId = process.env.AZURE_POSTGRESQL_CLIENTID;
   // const credential = new DefaultAzureCredential({
   //     managedIdentityClientId: clientId
   // });
   
   // For service principal.
   // const tenantId = process.env.AZURE_POSTGRESQL_TENANTID;
   // const clientId = process.env.AZURE_POSTGRESQL_CLIENTID;
   // const clientSecret = process.env.AZURE_POSTGRESQL_CLIENTSECRET;
   
   // Acquire the access token.
   var accessToken = await credential.getToken('https://ossrdbms-aad.database.windows.net/.default');
   
   // Use the token and the connection information from the environment variables added by Service Connector to establish the connection.
   (async () => {
   const client = new Client({
       host: process.env.AZURE_POSTGRESQL_HOST,
       user: process.env.AZURE_POSTGRESQL_USER,
       password: accesstoken.token,
       database: process.env.AZURE_POSTGRESQL_DATABASE,
       port: Number(process.env.AZURE_POSTGRESQL_PORT) ,
       ssl: process.env.AZURE_POSTGRESQL_SSL
   });
   await client.connect();
   
   await client.end();
   })();
   

For PHP, there's not a plugin or library for passwordless connections. You can get an access token for the managed identity or service principal and use it as the password to connect to the database. The access token can be acquired using Azure REST API.

1. In code, get the access token using REST API with your favorite library.

   For user-assigned identity and system-assigned identity, App Service and Container Apps provides an internally accessible REST endpoint to retrieve tokens for managed identities by defining two environment variables: IDENTITY_ENDPOINT and IDENTITY_HEADER. For more information, see REST endpoint reference. Get the access token by making an HTTP GET request to the identity endpoint, and use https://ossrdbms-aad.database.windows.net as resource in the query. For user-assigned identity, please include the client ID from the environment variables added by Service Connector in the query as well.

   For service principal, refer to the Azure AD service-to-service access token request to see the details of how to acquire access token. Make the POST request the scope of https://ossrdbms-aad.database.windows.net/.default and with the tenant ID, client ID and client secret of the service principal from the environment variables added by Service Connector.

2. Combine the access token and the PostgreSQL connection sting from environment variables added by Service Connector service to establish the connection.

   <?php
   $conn_string = sprintf("%s password=", getenv('AZURE_POSTGRESQL_CONNECTIONSTRING'), $access_token);
   $dbconn = pg_connect($conn_string);
   ?>
   

For Ruby, there's not a plugin or library for passwordless connections. You can get an access token for the managed identity or service principal and use it as the password to connect to the database. The access token can be acquired using Azure REST API.

1. Install dependencies.

   gem install pg
   

2. In code, get the access token using REST API and PostgreSQL connection information from environment variables added by Service Connector service. Combine them to establish the connection. When using the code below, uncomment the part of the code snippet for the authentication type you want to use.

   App service and container Apps provides an internally accessible REST endpoint to retrieve tokens for managed identities. For more information, see REST endpoint reference.

   require 'pg'
   require 'dotenv/load'
   require 'net/http'
   require 'json'
   
   # Uncomment the following lines corresponding to the authentication type you want to use.
   # For system-assigned identity.
   # uri = URI(ENV['IDENTITY_ENDPOINT'] + '?resource=https://ossrdbms-aad.database.windows.net&api-version=2019-08-01')
   # res = Net::HTTP.get_response(uri, {'X-IDENTITY-HEADER' => ENV['IDENTITY_HEADER'], 'Metadata' => 'true'})  
   
   # For user-assigned identity.
   # uri = URI(ENV[IDENTITY_ENDPOINT] + '?resource=https://ossrdbms-aad.database.windows.net&api-version=2019-08-01&client-id=' + ENV['AZURE_POSTGRESQL_CLIENTID'])
   # res = Net::HTTP.get_response(uri, {'X-IDENTITY-HEADER' => ENV['IDENTITY_HEADER'], 'Metadata' => 'true'})  
   
   # For service principal
   # uri = URI('https://login.microsoftonline.com/' + ENV['AZURE_POSTGRESQL_TENANTID'] + '/oauth2/v2.0/token')
   # params = {
   #     :grant_type => 'client_credentials',
   #     :client_id: => ENV['AZURE_POSTGRESQL_CLIENTID'],
   #     :client_secret => ENV['AZURE_POSTGRESQL_CLIENTSECRET'],
   #     :scope => 'https://ossrdbms-aad.database.windows.net/.default'
   # }
   # req = Net::HTTP::POST.new(uri)
   # req.set_form_data(params)
   # req['Content-Type'] = 'application/x-www-form-urlencoded'
   # res = Net::HTTP.start(uri.hostname, uri.port, :use_ssl => true) do |http|
   #   http.request(req)
   
   parsed = JSON.parse(res.body)
   access_token = parsed["access_token"]
   
   # Use the token and the connection string from the environment variables added by Service Connector to establish the connection.
   conn = PG::Connection.new(
       connection_string: ENV['AZURE_POSTGRESQL_CONNECTIONSTRING'] + " password="  + access_token,
   )
   

   Refer to the Azure AD service-to-service access token request to see more details of how to acquire access token for service principal.

For other languages, use the connection properties that Service Connector sets to the environment variables to connect the database. For environment variable details, see Integrate Azure Database for PostgreSQL with Service Connector.

For .NET, there's not a plugin or library to support passwordless connections. You can get an access token for the managed identity or service principal using client library like Azure.Identity. Then you can use the access token as the password to connect to the database. When using the code below, uncomment the part of the code snippet for the authentication type you want to use.

using Azure.Identity;
using Azure.Core;
using Npgsql;

// Uncomment the following lines corresponding to the authentication type you want to use.
// For system-assigned identity.
// var sqlServerTokenProvider = new DefaultAzureCredential();

// For user-assigned identity.
// var sqlServerTokenProvider = new DefaultAzureCredential(
//     new DefaultAzureCredentialOptions
//     {
//         ManagedIdentityClientId = Environment.GetEnvironmentVariable("AZURE_POSTGRESQL_CLIENTID");
//     }
// );

// For service principal.
// var tenantId = Environment.GetEnvironmentVariable("AZURE_POSTGRESQL_TENANTID");
// var clientId = Environment.GetEnvironmentVariable("AZURE_POSTGRESQL_CLIENTID");
// var clientSecret = Environment.GetEnvironmentVariable("AZURE_POSTGRESQL_CLIENTSECRET");
// var sqlServerTokenProvider = new ClientSecretCredential(tenantId, clientId, clientSecret);

// Acquire the access token. 
AccessToken accessToken = await sqlServerTokenProvider.GetTokenAsync(
    new TokenRequestContext(scopes: new string[]
    {
        "https://ossrdbms-aad.database.windows.net/.default"
    }));

// Combine the token with the connection string from the environment variables provided by Service Connector.
string connectionString =
    $"{Environment.GetEnvironmentVariable("AZURE_POSTGRESQL_CONNECTIONSTRING")};Password={accessToken.Token}";

// Establish the connection.
using (var connection = new NpgsqlConnection(connectionString))
{
    Console.WriteLine("Opening connection using access token...");
    connection.Open();
}

1. Add the following dependencies in your pom.xml file:

   <dependency>
       <groupId>org.postgresql</groupId>
       <artifactId>postgresql</artifactId>
       <version>42.3.6</version>
   </dependency>
   <dependency>
       <groupId>com.azure</groupId>
       <artifactId>azure-identity-extensions</artifactId>
       <version>1.1.5</version>
   </dependency>
   

2. Get the connection string from environment variables and add the plugin name to connect to the database:

   import java.sql.*;
   
   String url = System.getenv("AZURE_POSTGRESQL_CONNECTIONSTRING");
   String pluginName = "com.Azure.identity.extensions.jdbc.postgresql.AzurePostgresqlAuthenticationPlugin";  
   Connection connection = DriverManager.getConnection(url + "&authenticationPluginClassName=" + pluginName);
   

For more information, see the following resources:

• Tutorial: Connect to PostgreSQL Database from a Java Quarkus Container App without secrets using a managed identity
• Tutorial: Connect to a PostgreSQL Database from Java Tomcat App Service without secrets using a managed identity
• Quickstart: Use Java and JDBC with Azure Database for PostgreSQL Flexible Server
• Migrate an application to use passwordless connections with Azure Database for PostgreSQL

For a Spring application, if you create a connection with option --client-type springboot, Service Connector sets the properties spring.datasource.azure.passwordless-enabled, spring.datasource.url, and spring.datasource.username to Azure Spring Apps.

Update your application following the tutorial Bind an Azure Database for PostgreSQL to your application in Azure Spring Apps. Remember to remove the spring.datasource.password configuration property if it was set before and add the correct dependencies to your Spring application.

For more tutorials, see Use Spring Data JDBC with Azure Database for PostgreSQL and Tutorial: Deploy a Spring application to Azure Spring Apps with a passwordless connection to an Azure database.

1. Install dependencies.

   pip install azure-identity
   pip install psycopg2-binary
   pip freeze > requirements.txt # Save the dependencies to a file
   

2. Get access token using azure-identity library and use the token as password. Get connection information from the environment variables added by Service Connector. When using the code below, uncomment the part of the code snippet for the authentication type you want to use.

   from azure.identity import DefaultAzureCredential
   import psycopg2
   
   # Uncomment the following lines corresponding to the authentication type you want to use.
   # For system-assigned identity.
   # cred = DefaultAzureCredential()
   
   # For user-assigned identity.
   # managed_identity_client_id = os.getenv('AZURE_POSTGRESQL_CLIENTID')
   # cred = ManagedIdentityCredential(client_id=managed_identity_client_id)   
   
   # For service principal.
   # tenant_id = os.getenv('AZURE_POSTGRESQL_TENANTID')
   # client_id = os.getenv('AZURE_POSTGRESQL_CLIENTID')
   # client_secret = os.getenv('AZURE_POSTGRESQL_CLIENTSECRET')
   # cred = ClientSecretCredential(tenant_id=tenant_id, client_id=client_id, client_secret=client_secret)
   
   # Acquire the access token
   accessToken = cred.get_token('https://ossrdbms-aad.database.windows.net/.default')
   
   # Combine the token with the connection string from the environment variables added by Service Connector to establish the connection.
   conn_string = os.getenv('AZURE_POSTGRESQL_CONNECTIONSTRING')
   conn = psycopg2.connect(conn_string + ' password=' + accessToken.token) 
   

1. Install dependencies.

   pip install azure-identity
   

2. Get access token using azure-identity library using environment variables added by Service Connector. When using the code below, uncomment the part of the code snippet for the authentication type you want to use.

   from azure.identity import DefaultAzureCredential
   import psycopg2
   
   # Uncomment the following lines corresponding to the authentication type you want to use.
   # For system-assigned identity.
   # credential = DefaultAzureCredential()
   
   # For user-assigned identity.
   # managed_identity_client_id = os.getenv('AZURE_POSTGRESQL_CLIENTID')
   # cred = ManagedIdentityCredential(client_id=managed_identity_client_id)    
   
   # For service principal.
   # tenant_id = os.getenv('AZURE_POSTGRESQL_TENANTID')
   # client_id = os.getenv('AZURE_POSTGRESQL_CLIENTID')
   # client_secret = os.getenv('AZURE_POSTGRESQL_CLIENTSECRET')
   # cred = ClientSecretCredential(tenant_id=tenant_id, client_id=client_id, client_secret=client_secret)
   
   # Acquire the access token.
   accessToken = cred.get_token('https://ossrdbms-aad.database.windows.net/.default')
   

3. In setting file, get Azure PostgreSQL database information from environment variables added by Service Connector service. Use accessToken acquired in previous step to access the database.

   # In your setting file, eg. settings.py
   host = os.getenv('AZURE_POSTGRESQL_HOST')
   user = os.getenv('AZURE_POSTGRESQL_USER')
   password = accessToken.token # this is accessToken acquired from above step.
   database = os.getenv('AZURE_POSTGRESQL_NAME')
   
   DATABASES = {
       'default': {
           'ENGINE': 'django.db.backends.postgresql_psycopg2',
           'NAME': database,
           'USER': user,
           'PASSWORD': password,
           'HOST': host,
           'PORT': '5432',  # Port is 5432 by default 
           'OPTIONS': {'sslmode': 'require'},
       }
   }
   

1. Install dependencies.

   go get github.com/lib/pq
   go get "github.com/Azure/azure-sdk-for-go/sdk/azidentity"
   go get "github.com/Azure/azure-sdk-for-go/sdk/azcore"
   

2. In code, get access token using azidentity, then use it as password to connect to Azure PostgreSQL along with connection information provided by Service Connector. When using the code below, uncomment the part of the code snippet for the authentication type you want to use.

   import (
   "database/sql"
   "fmt"
   "os"
   
   "context"
   
   "github.com/Azure/azure-sdk-for-go/sdk/azcore/policy"
   "github.com/Azure/azure-sdk-for-go/sdk/azidentity"
   
    _ "github.com/lib/pq"
   )    
   
   // Uncomment the following lines corresponding to the authentication type you want to use.
   // For system-assigned identity.
   // cred, err := azidentity.NewDefaultAzureCredential(nil)
   
   // For user-assigned identity.
   // clientid := os.Getenv("AZURE_POSTGRESQL_CLIENTID")
   // azidentity.ManagedIdentityCredentialOptions.ID := clientid
   // options := &azidentity.ManagedIdentityCredentialOptions{ID: clientid}
   // cred, err := azidentity.NewManagedIdentityCredential(options)
   
   // For service principal.
   // clientid := os.Getenv("AZURE_POSTGRESQL_CLIENTID")
   // tenantid := os.Getenv("AZURE_POSTGRESQL_TENANTID")
   // clientsecret := os.Getenv("AZURE_POSTGRESQL_CLIENTSECRET")
   // cred, err := azidentity.NewClientSecretCredential(tenantid, clientid, clientsecret, &azidentity.ClientSecretCredentialOptions{})
   
   if err != nil {
       // error handling
   }
   
   // Acquire the access token
   ctx, cancel := context.WithTimeout(context.Background(), 30*time.Second)
   token, err := cred.GetToken(ctx, policy.TokenRequestOptions{
       Scopes: []string("https://ossrdbms-aad.database.windows.net/.default"),
   })
   
   // Combine the token with the connection string from the environment variables added by Service Connector to establish the connection.
   connectionString := os.Getenv("AZURE_POSTGRESQL_CONNECTIONSTRING") + " password=" + token.Token
   
   conn, err := sql.Open("postgres", connectionString)
    if err != nil {
    	panic(err)
    }
   
    conn.Close()
   

1. Install dependencies.

   npm install --save @azure/identity
   npm install --save pg
   

2. In code, get the access token using @azure/identity and PostgreSQL connection information from environment variables added by Service Connector service. Combine them to establish the connection. When using the code below, uncomment the part of the code snippet for the authentication type you want to use.

   import { DefaultAzureCredential, ClientSecretCredential } from "@azure/identity";
   const { Client } = require('pg');
   
   // Uncomment the following lines corresponding to the authentication type you want to use.  
   // For system-assigned identity.
   // const credential = new DefaultAzureCredential();
   
   // For user-assigned identity.
   // const clientId = process.env.AZURE_POSTGRESQL_CLIENTID;
   // const credential = new DefaultAzureCredential({
   //     managedIdentityClientId: clientId
   // });
   
   // For service principal.
   // const tenantId = process.env.AZURE_POSTGRESQL_TENANTID;
   // const clientId = process.env.AZURE_POSTGRESQL_CLIENTID;
   // const clientSecret = process.env.AZURE_POSTGRESQL_CLIENTSECRET;
   
   // Acquire the access token.
   var accessToken = await credential.getToken('https://ossrdbms-aad.database.windows.net/.default');
   
   // Use the token and the connection information from the environment variables added by Service Connector to establish the connection.
   (async () => {
   const client = new Client({
       host: process.env.AZURE_POSTGRESQL_HOST,
       user: process.env.AZURE_POSTGRESQL_USER,
       password: accesstoken.token,
       database: process.env.AZURE_POSTGRESQL_DATABASE,
       port: Number(process.env.AZURE_POSTGRESQL_PORT) ,
       ssl: process.env.AZURE_POSTGRESQL_SSL
   });
   await client.connect();
   
   await client.end();
   })();
   

For PHP, there's not a plugin or library for passwordless connections. You can get an access token for the managed identity or service principal and use it as the password to connect to the database. The access token can be acquired using Azure REST API.

1. In code, get the access token using REST API with your favorite library.

   For user-assigned identity and system-assigned identity, App Service and Container Apps provides an internally accessible REST endpoint to retrieve tokens for managed identities by defining two environment variables: IDENTITY_ENDPOINT and IDENTITY_HEADER. For more information, see REST endpoint reference. Get the access token by making an HTTP GET request to the identity endpoint, and use https://ossrdbms-aad.database.windows.net as resource in the query. For user-assigned identity, please include the client ID from the environment variables added by Service Connector in the query as well.

   For service principal, refer to the Azure AD service-to-service access token request to see the details of how to acquire access token. Make the POST request the scope of https://ossrdbms-aad.database.windows.net/.default and with the tenant ID, client ID and client secret of the service principal from the environment variables added by Service Connector.

2. Combine the access token and the PostgreSQL connection sting from environment variables added by Service Connector service to establish the connection.

   <?php
   $conn_string = sprintf("%s password=", getenv('AZURE_POSTGRESQL_CONNECTIONSTRING'), $access_token);
   $dbconn = pg_connect($conn_string);
   ?>
   

For Ruby, there's not a plugin or library for passwordless connections. You can get an access token for the managed identity or service principal and use it as the password to connect to the database. The access token can be acquired using Azure REST API.

1. Install dependencies.

   gem install pg
   

2. In code, get the access token using REST API and PostgreSQL connection information from environment variables added by Service Connector service. Combine them to establish the connection. When using the code below, uncomment the part of the code snippet for the authentication type you want to use.

   App service and container Apps provides an internally accessible REST endpoint to retrieve tokens for managed identities. For more information, see REST endpoint reference.

   require 'pg'
   require 'dotenv/load'
   require 'net/http'
   require 'json'
   
   # Uncomment the following lines corresponding to the authentication type you want to use.
   # For system-assigned identity.
   # uri = URI(ENV['IDENTITY_ENDPOINT'] + '?resource=https://ossrdbms-aad.database.windows.net&api-version=2019-08-01')
   # res = Net::HTTP.get_response(uri, {'X-IDENTITY-HEADER' => ENV['IDENTITY_HEADER'], 'Metadata' => 'true'})  
   
   # For user-assigned identity.
   # uri = URI(ENV[IDENTITY_ENDPOINT] + '?resource=https://ossrdbms-aad.database.windows.net&api-version=2019-08-01&client-id=' + ENV['AZURE_POSTGRESQL_CLIENTID'])
   # res = Net::HTTP.get_response(uri, {'X-IDENTITY-HEADER' => ENV['IDENTITY_HEADER'], 'Metadata' => 'true'})  
   
   # For service principal
   # uri = URI('https://login.microsoftonline.com/' + ENV['AZURE_POSTGRESQL_TENANTID'] + '/oauth2/v2.0/token')
   # params = {
   #     :grant_type => 'client_credentials',
   #     :client_id: => ENV['AZURE_POSTGRESQL_CLIENTID'],
   #     :client_secret => ENV['AZURE_POSTGRESQL_CLIENTSECRET'],
   #     :scope => 'https://ossrdbms-aad.database.windows.net/.default'
   # }
   # req = Net::HTTP::POST.new(uri)
   # req.set_form_data(params)
   # req['Content-Type'] = 'application/x-www-form-urlencoded'
   # res = Net::HTTP.start(uri.hostname, uri.port, :use_ssl => true) do |http|
   #   http.request(req)
   
   parsed = JSON.parse(res.body)
   access_token = parsed["access_token"]
   
   # Use the token and the connection string from the environment variables added by Service Connector to establish the connection.
   conn = PG::Connection.new(
       connection_string: ENV['AZURE_POSTGRESQL_CONNECTIONSTRING'] + " password="  + access_token,
   )
   

   Refer to the Azure AD service-to-service access token request to see more details of how to acquire access token for service principal.

For other languages, use the connection properties that Service Connector sets to the environment variables to connect the database. For environment variable details, see Integrate Azure Database for PostgreSQL with Service Connector.

1. Install dependencies. Follow the guidance to install Npgsql
2. In code, get the PostgreSQL connection string from environment variables added by Service Connector service. To set TSL configurations for PostgreSQL server, refer to these steps.

   using System;
   using Npgsql;
   
   string connectionString = Environment.GetEnvironmentVariable("AZURE_POSTGRESQL_CONNECTIONSTRING");
   using (NpgsqlConnection connection = new NpgsqlConnection(connectionString))
   {
       connection.Open();
   }
   

1. Install dependencies. Follow the guidance to install pgJDBC.
2. In code, get the PostgreSQL connection string from environment variables added by Service Connector service. To set TSL configurations for PostgreSQL server, refer to these steps.

   import java.sql.Connection;
   import java.sql.DriverManager;
   import java.sql.SQLException;
   
   String connectionString = System.getenv("AZURE_POSTGRESQL_CONNECTIONSTRING");
   Connection connection = null;
   try {
       connection = DriverManager.getConnection(connectionString);
       System.out.println("Connection successful!");
   } catch (SQLException e){
       System.out.println(e.getMessage());
   }
   

1. Install the Spring Cloud Azure Starter JDBC PostgreSQL module by adding the following dependencies to your pom.xml file. Find the version of Spring Cloud Azure here.

   <dependencyManagement>
       <dependencies>
           <dependency>
               <groupId>com.azure.spring</groupId>
               <artifactId>spring-cloud-azure-dependencies</artifactId>
               <version>4.11.0</version>
               <type>pom</type>
               <scope>import</scope>
           </dependency>
           <dependency>
               <groupId>com.azure.spring</groupId>
               <artifactId>spring-cloud-azure-starter-jdbc-postgresql</artifactId>
           </dependency>
       </dependencies>
   </dependencyManagement>
   

2. Set up a Spring App application, more details in this section. To set TSL configurations for PostgreSQL server, refer to these steps.

1. Install dependencies. Follow the guidance to install psycopg2.
2. In code, get the PostgreSQL connection information from environment variables added by Service Connector service. To set TSL configurations for PostgreSQL server, refer to these steps.

   import os
   import psycopg2
   
   connection_string = os.getenv('AZURE_POSTGRESQL_CONNECTIONSTRING')
   connection = psycopg2.connect(connection_string)
   print("Connection established")
   
   connection.close()
   

1. Install dependencies. Follow the guidance to install Django and psycopg2.

   pip install django
   pip install psycopg2
   

2. In setting file, get the PostgreSQL database information from environment variables added by Service Connector service. To set TSL configurations for PostgreSQL server, refer to these steps.

   # in your setting file, eg. settings.py
   host = os.getenv('AZURE_POSTGRESQL_HOST')
   user = os.getenv('AZURE_POSTGRESQL_USER')
   password = os.getenv('AZURE_POSTGRESQL_PASSWORD')
   database = os.getenv('AZURE_POSTGRESQL_NAME')
   
   DATABASES = {
       'default': {
           'ENGINE': 'django.db.backends.postgresql_psycopg2',
           'NAME': database,
           'USER': user,
           'PASSWORD': password,
           'HOST': host,
           'PORT': '5432',  # Port is 5432 by default 
           'OPTIONS': {'sslmode': 'require'},
       }
   }
   

1. Install dependencies.

   go get github.com/lib/pq
   

2. In code, get the PostgreSQL connection string from environment variables added by Service Connector service. To set TSL configurations for PostgreSQL server, refer to these steps.

   import (
   "database/sql"
   "fmt"
   "os"
   
    _ "github.com/lib/pq"
   )
   
   connectionString := os.Getenv("AZURE_POSTGRESQL_CONNECTIONSTRING")
   conn, err := sql.Open("postgres", connectionString)
    if err != nil {
    	panic(err)
    }
   
    conn.Close()
   

1. Install dependencies.

   npm install pg dotenv
   

2. In code, get the PostgreSQL connection information from environment variables added by Service Connector service. To set TSL configurations for PostgreSQL server, refer to these steps.

   const { Client } = require('pg');
   
   (async () => {
    const client = new Client({
        host: process.env.AZURE_POSTGRESQL_HOST,
        user: process.env.AZURE_POSTGRESQL_USER,
        password: process.env.AZURE_POSTGRESQL_PASSWORD,
        database: process.env.AZURE_POSTGRESQL_DATABASE,
        port: Number(process.env.AZURE_POSTGRESQL_PORT) ,
        ssl: process.env.AZURE_POSTGRESQL_SSL
    });
    await client.connect();
   
    await client.end();
   })();
   

1. In code, get the PostgreSQL connection information from environment variables added by Service Connector service. To set TSL configurations for PostgreSQL server, refer to these steps.

   <?php
   $conn_string = getenv('AZURE_POSTGRESQL_CONNECTIONSTRING');
   $dbconn = pg_connect($conn_string);
   ?>
   

1. Install dependencies.

   gem install pg
   

2. In code, get the PostgreSQL connection information from environment variables added by Service Connector service. To set TSL configurations for PostgreSQL server, refer to these steps.

   require 'pg'
   require 'dotenv/load'
   
   begin
       conn = PG::Connection.new(
           connection_string: ENV['AZURE_POSTGRESQL_CONNECTIONSTRING'],
       )
   rescue PG::Error => e
       puts e.message
   
   ensure
       connection.close if connection
   end
   

For other languages, use the connection properties that Service Connector sets to the environment variables to connect the database. For environment variable details, see Integrate Azure Database for PostgreSQL with Service Connector.

For .NET, there's not a plugin or library to support passwordless connections. You can get an access token for the managed identity or service principal using client library like Azure.Identity. Then you can use the access token as the password to connect to the database. When using the code below, uncomment the part of the code snippet for the authentication type you want to use.

using Azure.Identity;
using Azure.Core;
using Npgsql;

// Uncomment the following lines corresponding to the authentication type you want to use.
// For system-assigned identity.
// var sqlServerTokenProvider = new DefaultAzureCredential();

// For user-assigned identity.
// var sqlServerTokenProvider = new DefaultAzureCredential(
//     new DefaultAzureCredentialOptions
//     {
//         ManagedIdentityClientId = Environment.GetEnvironmentVariable("AZURE_POSTGRESQL_CLIENTID");
//     }
// );

// For service principal.
// var tenantId = Environment.GetEnvironmentVariable("AZURE_POSTGRESQL_TENANTID");
// var clientId = Environment.GetEnvironmentVariable("AZURE_POSTGRESQL_CLIENTID");
// var clientSecret = Environment.GetEnvironmentVariable("AZURE_POSTGRESQL_CLIENTSECRET");
// var sqlServerTokenProvider = new ClientSecretCredential(tenantId, clientId, clientSecret);

// Acquire the access token. 
AccessToken accessToken = await sqlServerTokenProvider.GetTokenAsync(
    new TokenRequestContext(scopes: new string[]
    {
        "https://ossrdbms-aad.database.windows.net/.default"
    }));

// Combine the token with the connection string from the environment variables provided by Service Connector.
string connectionString =
    $"{Environment.GetEnvironmentVariable("AZURE_POSTGRESQL_CONNECTIONSTRING")};Password={accessToken.Token}";

// Establish the connection.
using (var connection = new NpgsqlConnection(connectionString))
{
    Console.WriteLine("Opening connection using access token...");
    connection.Open();
}

1. Add the following dependencies in your pom.xml file:

   <dependency>
       <groupId>org.postgresql</groupId>
       <artifactId>postgresql</artifactId>
       <version>42.3.6</version>
   </dependency>
   <dependency>
       <groupId>com.azure</groupId>
       <artifactId>azure-identity-extensions</artifactId>
       <version>1.1.5</version>
   </dependency>
   

2. Get the connection string from environment variables and add the plugin name to connect to the database:

   import java.sql.*;
   
   String url = System.getenv("AZURE_POSTGRESQL_CONNECTIONSTRING");
   String pluginName = "com.Azure.identity.extensions.jdbc.postgresql.AzurePostgresqlAuthenticationPlugin";  
   Connection connection = DriverManager.getConnection(url + "&authenticationPluginClassName=" + pluginName);
   

For more information, see the following resources:

• Tutorial: Connect to PostgreSQL Database from a Java Quarkus Container App without secrets using a managed identity
• Tutorial: Connect to a PostgreSQL Database from Java Tomcat App Service without secrets using a managed identity
• Quickstart: Use Java and JDBC with Azure Database for PostgreSQL Flexible Server
• Migrate an application to use passwordless connections with Azure Database for PostgreSQL

For a Spring application, if you create a connection with option --client-type springboot, Service Connector sets the properties spring.datasource.azure.passwordless-enabled, spring.datasource.url, and spring.datasource.username to Azure Spring Apps.

Update your application following the tutorial Bind an Azure Database for PostgreSQL to your application in Azure Spring Apps. Remember to remove the spring.datasource.password configuration property if it was set before and add the correct dependencies to your Spring application.

For more tutorials, see Use Spring Data JDBC with Azure Database for PostgreSQL and Tutorial: Deploy a Spring application to Azure Spring Apps with a passwordless connection to an Azure database.

1. Install dependencies.

   pip install azure-identity
   pip install psycopg2-binary
   pip freeze > requirements.txt # Save the dependencies to a file
   

2. Get access token using azure-identity library and use the token as password. Get connection information from the environment variables added by Service Connector. When using the code below, uncomment the part of the code snippet for the authentication type you want to use.

   from azure.identity import DefaultAzureCredential
   import psycopg2
   
   # Uncomment the following lines corresponding to the authentication type you want to use.
   # For system-assigned identity.
   # cred = DefaultAzureCredential()
   
   # For user-assigned identity.
   # managed_identity_client_id = os.getenv('AZURE_POSTGRESQL_CLIENTID')
   # cred = ManagedIdentityCredential(client_id=managed_identity_client_id)   
   
   # For service principal.
   # tenant_id = os.getenv('AZURE_POSTGRESQL_TENANTID')
   # client_id = os.getenv('AZURE_POSTGRESQL_CLIENTID')
   # client_secret = os.getenv('AZURE_POSTGRESQL_CLIENTSECRET')
   # cred = ClientSecretCredential(tenant_id=tenant_id, client_id=client_id, client_secret=client_secret)
   
   # Acquire the access token
   accessToken = cred.get_token('https://ossrdbms-aad.database.windows.net/.default')
   
   # Combine the token with the connection string from the environment variables added by Service Connector to establish the connection.
   conn_string = os.getenv('AZURE_POSTGRESQL_CONNECTIONSTRING')
   conn = psycopg2.connect(conn_string + ' password=' + accessToken.token) 
   

1. Install dependencies.

   pip install azure-identity
   

2. Get access token using azure-identity library using environment variables added by Service Connector. When using the code below, uncomment the part of the code snippet for the authentication type you want to use.

   from azure.identity import DefaultAzureCredential
   import psycopg2
   
   # Uncomment the following lines corresponding to the authentication type you want to use.
   # For system-assigned identity.
   # credential = DefaultAzureCredential()
   
   # For user-assigned identity.
   # managed_identity_client_id = os.getenv('AZURE_POSTGRESQL_CLIENTID')
   # cred = ManagedIdentityCredential(client_id=managed_identity_client_id)    
   
   # For service principal.
   # tenant_id = os.getenv('AZURE_POSTGRESQL_TENANTID')
   # client_id = os.getenv('AZURE_POSTGRESQL_CLIENTID')
   # client_secret = os.getenv('AZURE_POSTGRESQL_CLIENTSECRET')
   # cred = ClientSecretCredential(tenant_id=tenant_id, client_id=client_id, client_secret=client_secret)
   
   # Acquire the access token.
   accessToken = cred.get_token('https://ossrdbms-aad.database.windows.net/.default')
   

3. In setting file, get Azure PostgreSQL database information from environment variables added by Service Connector service. Use accessToken acquired in previous step to access the database.

   # In your setting file, eg. settings.py
   host = os.getenv('AZURE_POSTGRESQL_HOST')
   user = os.getenv('AZURE_POSTGRESQL_USER')
   password = accessToken.token # this is accessToken acquired from above step.
   database = os.getenv('AZURE_POSTGRESQL_NAME')
   
   DATABASES = {
       'default': {
           'ENGINE': 'django.db.backends.postgresql_psycopg2',
           'NAME': database,
           'USER': user,
           'PASSWORD': password,
           'HOST': host,
           'PORT': '5432',  # Port is 5432 by default 
           'OPTIONS': {'sslmode': 'require'},
       }
   }
   

1. Install dependencies.

   go get github.com/lib/pq
   go get "github.com/Azure/azure-sdk-for-go/sdk/azidentity"
   go get "github.com/Azure/azure-sdk-for-go/sdk/azcore"
   

2. In code, get access token using azidentity, then use it as password to connect to Azure PostgreSQL along with connection information provided by Service Connector. When using the code below, uncomment the part of the code snippet for the authentication type you want to use.

   import (
   "database/sql"
   "fmt"
   "os"
   
   "context"
   
   "github.com/Azure/azure-sdk-for-go/sdk/azcore/policy"
   "github.com/Azure/azure-sdk-for-go/sdk/azidentity"
   
    _ "github.com/lib/pq"
   )    
   
   // Uncomment the following lines corresponding to the authentication type you want to use.
   // For system-assigned identity.
   // cred, err := azidentity.NewDefaultAzureCredential(nil)
   
   // For user-assigned identity.
   // clientid := os.Getenv("AZURE_POSTGRESQL_CLIENTID")
   // azidentity.ManagedIdentityCredentialOptions.ID := clientid
   // options := &azidentity.ManagedIdentityCredentialOptions{ID: clientid}
   // cred, err := azidentity.NewManagedIdentityCredential(options)
   
   // For service principal.
   // clientid := os.Getenv("AZURE_POSTGRESQL_CLIENTID")
   // tenantid := os.Getenv("AZURE_POSTGRESQL_TENANTID")
   // clientsecret := os.Getenv("AZURE_POSTGRESQL_CLIENTSECRET")
   // cred, err := azidentity.NewClientSecretCredential(tenantid, clientid, clientsecret, &azidentity.ClientSecretCredentialOptions{})
   
   if err != nil {
       // error handling
   }
   
   // Acquire the access token
   ctx, cancel := context.WithTimeout(context.Background(), 30*time.Second)
   token, err := cred.GetToken(ctx, policy.TokenRequestOptions{
       Scopes: []string("https://ossrdbms-aad.database.windows.net/.default"),
   })
   
   // Combine the token with the connection string from the environment variables added by Service Connector to establish the connection.
   connectionString := os.Getenv("AZURE_POSTGRESQL_CONNECTIONSTRING") + " password=" + token.Token
   
   conn, err := sql.Open("postgres", connectionString)
    if err != nil {
    	panic(err)
    }
   
    conn.Close()
   

1. Install dependencies.

   npm install --save @azure/identity
   npm install --save pg
   

2. In code, get the access token using @azure/identity and PostgreSQL connection information from environment variables added by Service Connector service. Combine them to establish the connection. When using the code below, uncomment the part of the code snippet for the authentication type you want to use.

   import { DefaultAzureCredential, ClientSecretCredential } from "@azure/identity";
   const { Client } = require('pg');
   
   // Uncomment the following lines corresponding to the authentication type you want to use.  
   // For system-assigned identity.
   // const credential = new DefaultAzureCredential();
   
   // For user-assigned identity.
   // const clientId = process.env.AZURE_POSTGRESQL_CLIENTID;
   // const credential = new DefaultAzureCredential({
   //     managedIdentityClientId: clientId
   // });
   
   // For service principal.
   // const tenantId = process.env.AZURE_POSTGRESQL_TENANTID;
   // const clientId = process.env.AZURE_POSTGRESQL_CLIENTID;
   // const clientSecret = process.env.AZURE_POSTGRESQL_CLIENTSECRET;
   
   // Acquire the access token.
   var accessToken = await credential.getToken('https://ossrdbms-aad.database.windows.net/.default');
   
   // Use the token and the connection information from the environment variables added by Service Connector to establish the connection.
   (async () => {
   const client = new Client({
       host: process.env.AZURE_POSTGRESQL_HOST,
       user: process.env.AZURE_POSTGRESQL_USER,
       password: accesstoken.token,
       database: process.env.AZURE_POSTGRESQL_DATABASE,
       port: Number(process.env.AZURE_POSTGRESQL_PORT) ,
       ssl: process.env.AZURE_POSTGRESQL_SSL
   });
   await client.connect();
   
   await client.end();
   })();
   

For PHP, there's not a plugin or library for passwordless connections. You can get an access token for the managed identity or service principal and use it as the password to connect to the database. The access token can be acquired using Azure REST API.

1. In code, get the access token using REST API with your favorite library.

   For user-assigned identity and system-assigned identity, App Service and Container Apps provides an internally accessible REST endpoint to retrieve tokens for managed identities by defining two environment variables: IDENTITY_ENDPOINT and IDENTITY_HEADER. For more information, see REST endpoint reference. Get the access token by making an HTTP GET request to the identity endpoint, and use https://ossrdbms-aad.database.windows.net as resource in the query. For user-assigned identity, please include the client ID from the environment variables added by Service Connector in the query as well.

   For service principal, refer to the Azure AD service-to-service access token request to see the details of how to acquire access token. Make the POST request the scope of https://ossrdbms-aad.database.windows.net/.default and with the tenant ID, client ID and client secret of the service principal from the environment variables added by Service Connector.

2. Combine the access token and the PostgreSQL connection sting from environment variables added by Service Connector service to establish the connection.

   <?php
   $conn_string = sprintf("%s password=", getenv('AZURE_POSTGRESQL_CONNECTIONSTRING'), $access_token);
   $dbconn = pg_connect($conn_string);
   ?>
   

For Ruby, there's not a plugin or library for passwordless connections. You can get an access token for the managed identity or service principal and use it as the password to connect to the database. The access token can be acquired using Azure REST API.

1. Install dependencies.

   gem install pg
   

2. In code, get the access token using REST API and PostgreSQL connection information from environment variables added by Service Connector service. Combine them to establish the connection. When using the code below, uncomment the part of the code snippet for the authentication type you want to use.

   App service and container Apps provides an internally accessible REST endpoint to retrieve tokens for managed identities. For more information, see REST endpoint reference.

   require 'pg'
   require 'dotenv/load'
   require 'net/http'
   require 'json'
   
   # Uncomment the following lines corresponding to the authentication type you want to use.
   # For system-assigned identity.
   # uri = URI(ENV['IDENTITY_ENDPOINT'] + '?resource=https://ossrdbms-aad.database.windows.net&api-version=2019-08-01')
   # res = Net::HTTP.get_response(uri, {'X-IDENTITY-HEADER' => ENV['IDENTITY_HEADER'], 'Metadata' => 'true'})  
   
   # For user-assigned identity.
   # uri = URI(ENV[IDENTITY_ENDPOINT] + '?resource=https://ossrdbms-aad.database.windows.net&api-version=2019-08-01&client-id=' + ENV['AZURE_POSTGRESQL_CLIENTID'])
   # res = Net::HTTP.get_response(uri, {'X-IDENTITY-HEADER' => ENV['IDENTITY_HEADER'], 'Metadata' => 'true'})  
   
   # For service principal
   # uri = URI('https://login.microsoftonline.com/' + ENV['AZURE_POSTGRESQL_TENANTID'] + '/oauth2/v2.0/token')
   # params = {
   #     :grant_type => 'client_credentials',
   #     :client_id: => ENV['AZURE_POSTGRESQL_CLIENTID'],
   #     :client_secret => ENV['AZURE_POSTGRESQL_CLIENTSECRET'],
   #     :scope => 'https://ossrdbms-aad.database.windows.net/.default'
   # }
   # req = Net::HTTP::POST.new(uri)
   # req.set_form_data(params)
   # req['Content-Type'] = 'application/x-www-form-urlencoded'
   # res = Net::HTTP.start(uri.hostname, uri.port, :use_ssl => true) do |http|
   #   http.request(req)
   
   parsed = JSON.parse(res.body)
   access_token = parsed["access_token"]
   
   # Use the token and the connection string from the environment variables added by Service Connector to establish the connection.
   conn = PG::Connection.new(
       connection_string: ENV['AZURE_POSTGRESQL_CONNECTIONSTRING'] + " password="  + access_token,
   )
   

   Refer to the Azure AD service-to-service access token request to see more details of how to acquire access token for service principal.

For other languages, use the connection properties that Service Connector sets to the environment variables to connect the database. For environment variable details, see Integrate Azure Database for PostgreSQL with Service Connector.