Azure Key Vault Secrets (Java)

Securely store and manage secrets like passwords, API keys, and connection strings.

Installation

<dependency>
    <groupId>com.azure</groupId>
    <artifactId>azure-security-keyvault-secrets</artifactId>
    <version>4.9.0</version>
</dependency>

Client Creation

import com.azure.core.credential.TokenCredential;
import com.azure.identity.AzureIdentityEnvVars;
import com.azure.identity.DefaultAzureCredentialBuilder;
import com.azure.identity.ManagedIdentityCredentialBuilder;
import com.azure.security.keyvault.secrets.SecretClient;
import com.azure.security.keyvault.secrets.SecretClientBuilder;

// Local dev: DefaultAzureCredential. Production: set AZURE_TOKEN_CREDENTIALS=prod or AZURE_TOKEN_CREDENTIALS=<specific_credential>
TokenCredential credential = new DefaultAzureCredentialBuilder()
    .requireEnvVars(AzureIdentityEnvVars.AZURE_TOKEN_CREDENTIALS)
    .build();
// Or use a specific credential directly in production:
// See https://learn.microsoft.com/java/api/overview/azure/identity-readme?view=azure-java-stable#credential-classes
// TokenCredential credential = new ManagedIdentityCredentialBuilder().build();

// Sync client
SecretClient secretClient = new SecretClientBuilder()
    .vaultUrl("https://<vault-name>.vault.azure.net")
    .credential(credential)
    .buildClient();

// Async client
SecretAsyncClient secretAsyncClient = new SecretClientBuilder()
    .vaultUrl("https://<vault-name>.vault.azure.net")
    .credential(credential)
    .buildAsyncClient();

Create/Set Secret

import com.azure.security.keyvault.secrets.models.KeyVaultSecret;

// Simple secret
KeyVaultSecret secret = secretClient.setSecret("database-password", "P@ssw0rd123!");
System.out.println("Secret name: " + secret.getName());
System.out.println("Secret ID: " + secret.getId());

// Secret with options
KeyVaultSecret secretWithOptions = secretClient.setSecret(
    new KeyVaultSecret("api-key", "sk_live_abc123xyz")
        .setProperties(new SecretProperties()
            .setContentType("application/json")
            .setExpiresOn(OffsetDateTime.now().plusYears(1))
            .setNotBefore(OffsetDateTime.now())
            .setEnabled(true)
            .setTags(Map.of(
                "environment", "production",
                "service", "payment-api"
            ))
        )
);

Get Secret

// Get latest version
KeyVaultSecret secret = secretClient.getSecret("database-password");
String value = secret.getValue();
System.out.println("Secret value: " + value);

// Get specific version
KeyVaultSecret specificVersion = secretClient.getSecret("database-password", "<version-id>");

// Get only properties (no value)
SecretProperties props = secretClient.getSecret("database-password").getProperties();
System.out.println("Enabled: " + props.isEnabled());
System.out.println("Created: " + props.getCreatedOn());

Update Secret Properties

// Get secret
KeyVaultSecret secret = secretClient.getSecret("api-key");

// Update properties (cannot update value - create new version instead)
secret.getProperties()
    .setEnabled(false)
    .setExpiresOn(OffsetDateTime.now().plusMonths(6))
    .setTags(Map.of("status", "rotating"));

SecretProperties updated = secretClient.updateSecretProperties(secret.getProperties());
System.out.println("Updated: " + updated.getUpdatedOn());

List Secrets

import com.azure.core.util.paging.PagedIterable;
import com.azure.security.keyvault.secrets.models.SecretProperties;

// List all secrets (properties only, no values)
for (SecretProperties secretProps : secretClient.listPropertiesOfSecrets()) {
    System.out.println("Secret: " + secretProps.getName());
    System.out.println("  Enabled: " + secretProps.isEnabled());
    System.out.println("  Created: " + secretProps.getCreatedOn());
    System.out.println("  Content-Type: " + secretProps.getContentType());
    
    // Get value if needed
    if (secretProps.isEnabled()) {
        KeyVaultSecret fullSecret = secretClient.getSecret(secretProps.getName());
        System.out.println("  Value: " + fullSecret.getValue().substring(0, 5) + "...");
    }
}

// List versions of a secret
for (SecretProperties version : secretClient.listPropertiesOfSecretVersions("database-password")) {
    System.out.println("Version: " + version.getVersion());
    System.out.println("Created: " + version.getCreatedOn());
    System.out.println("Enabled: " + version.isEnabled());
}

Delete Secret

import com.azure.core.util.polling.SyncPoller;
import com.azure.security.keyvault.secrets.models.DeletedSecret;

// Begin delete (returns poller for soft-delete enabled vaults)
SyncPoller<DeletedSecret, Void> deletePoller = secretClient.beginDeleteSecret("old-secret");

// Wait for deletion
DeletedSecret deletedSecret = deletePoller.poll().getValue();
System.out.println("Deleted on: " + deletedSecret.getDeletedOn());
System.out.println("Scheduled purge: " + deletedSecret.getScheduledPurgeDate());

deletePoller.waitForCompletion();

Recover Deleted Secret

// List deleted secrets
for (DeletedSecret deleted : secretClient.listDeletedSecrets()) {
    System.out.println("Deleted: " + deleted.getName());
    System.out.println("Deletion date: " + deleted.getDeletedOn());
}

// Recover deleted secret
SyncPoller<KeyVaultSecret, Void> recoverPoller = secretClient.beginRecoverDeletedSecret("old-secret");
recoverPoller.waitForCompletion();

KeyVaultSecret recovered = recoverPoller.getFinalResult();
System.out.println("Recovered: " + recovered.getName());

Purge Deleted Secret

// Permanently delete (cannot be recovered)
secretClient.purgeDeletedSecret("old-secret");

// Get deleted secret info first
DeletedSecret deleted = secretClient.getDeletedSecret("old-secret");
System.out.println("Will purge: " + deleted.getName());
secretClient.purgeDeletedSecret("old-secret");

Backup and Restore

// Backup secret (all versions)
byte[] backup = secretClient.backupSecret("important-secret");

// Save to file
Files.write(Paths.get("secret-backup.blob"), backup);

// Restore from backup
byte[] backupData = Files.readAllBytes(Paths.get("secret-backup.blob"));
KeyVaultSecret restored = secretClient.restoreSecretBackup(backupData);
System.out.println("Restored: " + restored.getName());

Async Operations

SecretAsyncClient asyncClient = new SecretClientBuilder()
    .vaultUrl("https://<vault>.vault.azure.net")
    .credential(new DefaultAzureCredentialBuilder().build())
    .buildAsyncClient();

// Set secret async
asyncClient.setSecret("async-secret", "async-value")
    .subscribe(
        secret -> System.out.println("Created: " + secret.getName()),
        error -> System.out.println("Error: " + error.getMessage())
    );

// Get secret async
asyncClient.getSecret("async-secret")
    .subscribe(secret -> System.out.println("Value: " + secret.getValue()));

// List secrets async
asyncClient.listPropertiesOfSecrets()
    .doOnNext(props -> System.out.println("Found: " + props.getName()))
    .subscribe();

Configuration Patterns

Load Multiple Secrets

public class ConfigLoader {
    private final SecretClient client;
    
    public ConfigLoader(String vaultUrl) {
        this.client = new SecretClientBuilder()
            .vaultUrl(vaultUrl)
            .credential(new DefaultAzureCredentialBuilder().build())
            .buildClient();
    }
    
    public Map<String, String> loadSecrets(List<String> secretNames) {
        Map<String, String> secrets = new HashMap<>();
        for (String name : secretNames) {
            try {
                KeyVaultSecret secret = client.getSecret(name);
                secrets.put(name, secret.getValue());
            } catch (ResourceNotFoundException e) {
                System.out.println("Secret not found: " + name);
            }
        }
        return secrets;
    }
}

// Usage
ConfigLoader loader = new ConfigLoader("https://my-vault.vault.azure.net");
Map<String, String> config = loader.loadSecrets(
    Arrays.asList("db-connection-string", "api-key", "jwt-secret")
);

Secret Rotation Pattern

public void rotateSecret(String secretName, String newValue) {
    // Get current secret
    KeyVaultSecret current = secretClient.getSecret(secretName);
    
    // Disable old version
    current.getProperties().setEnabled(false);
    secretClient.updateSecretProperties(current.getProperties());
    
    // Create new version with new value
    KeyVaultSecret newSecret = secretClient.setSecret(secretName, newValue);
    System.out.println("Rotated to version: " + newSecret.getProperties().getVersion());
}

Error Handling

import com.azure.core.exception.HttpResponseException;
import com.azure.core.exception.ResourceNotFoundException;

try {
    KeyVaultSecret secret = secretClient.getSecret("my-secret");
    System.out.println("Value: " + secret.getValue());
} catch (ResourceNotFoundException e) {
    System.out.println("Secret not found");
} catch (HttpResponseException e) {
    int status = e.getResponse().getStatusCode();
    if (status == 403) {
        System.out.println("Access denied - check permissions");
    } else if (status == 429) {
        System.out.println("Rate limited - retry later");
    } else {
        System.out.println("HTTP error: " + status);
    }
}

Secret Properties

Property	Description
name	Secret name
value	Secret value (string)
id	Full identifier URL
contentType	MIME type hint
enabled	Whether secret can be retrieved
notBefore	Activation time
expiresOn	Expiration time
createdOn	Creation timestamp
updatedOn	Last update timestamp
recoveryLevel	Soft-delete recovery level
tags	User-defined metadata

Environment Variables

AZURE_KEYVAULT_URL=https://<vault-name>.vault.azure.net  # Required for vault URL
AZURE_TOKEN_CREDENTIALS=prod  # Required only if DefaultAzureCredential is used in production

Best Practices

1. Enable Soft Delete - Protects against accidental deletion
2. Use Tags - Tag secrets with environment, service, owner
3. Set Expiration - Use setExpiresOn() for credentials that should rotate
4. Content Type - Set contentType to indicate format (e.g., application/json)
5. Version Management - Don't delete old versions immediately during rotation
6. Access Logging - Enable diagnostic logging on Key Vault
7. Least Privilege - Use separate vaults for different environments

Common Secret Types

// Database connection string
secretClient.setSecret(new KeyVaultSecret("db-connection", 
    "Server=myserver.database.windows.net;Database=mydb;...")
    .setProperties(new SecretProperties()
        .setContentType("text/plain")
        .setTags(Map.of("type", "connection-string"))));

// API key
secretClient.setSecret(new KeyVaultSecret("stripe-api-key", "sk_live_...")
    .setProperties(new SecretProperties()
        .setContentType("text/plain")
        .setExpiresOn(OffsetDateTime.now().plusYears(1))));

// JSON configuration
secretClient.setSecret(new KeyVaultSecret("app-config", 
    "{\"endpoint\":\"https://...\",\"key\":\"...\"}")
    .setProperties(new SecretProperties()
        .setContentType("application/json")));

// Certificate password
secretClient.setSecret(new KeyVaultSecret("cert-password", "CertP@ss!")
    .setProperties(new SecretProperties()
        .setContentType("text/plain")
        .setTags(Map.of("certificate", "my-cert"))));

Trigger Phrases

• "Key Vault secrets Java", "secret management Java"
• "store password", "store API key", "connection string"
• "retrieve secret", "rotate secret"
• "Azure secrets", "vault secrets"