MongoDB Audit Store

The MongoDB audit store (MongoDBSyncAuditStore) enables Flamingock to record execution history and ensure safe coordination across distributed deployments using MongoDB as the storage backend.

For a conceptual explanation of the audit store vs target systems, see Audit store vs target system.

Version compatibility

Component	Version Requirement
MongoDB Java Driver	4.0.0+

MongoDB 4.0+ is recommended for optimal performance and feature support.

Installation

Add the MongoDB Java sync driver dependency to your project:

Gradle

implementation("org.mongodb:mongodb-driver-sync:5.2.0")

Maven

<dependency>
    <groupId>org.mongodb</groupId>
    <artifactId>mongodb-driver-sync</artifactId>
    <version>5.2.0</version> <!-- 4.0.0+ supported -->
</dependency>

Basic setup

Configure the audit store using a MongoDB Target System to get the connection configuration:

var auditStore = MongoDBSyncAuditStore.from(mongoDbTargetSystem);

A MongoDBSyncAuditStore must be created from an existing MongoDBSyncTargetSystem.

This ensures that both components point to the same external MongoDB database:

• The Target System applies your business changes.
• The Audit Store stores the execution history associated with those changes.

Internally, the Audit Store takes the Target System’s connection settings (MongoClient + database name) and creates its own dedicated access handle, keeping audit operations isolated while still referring to the same physical system.

For a full conceptual explanation of this relationship, see Target Systems vs Audit Store.

Optional configurations can be added via .withXXX() methods.

Register Audit Store

Once created, you need to register this audit store with Flamingock. See Registering the community audit store for details.

Optional configuration (.withXXX() methods)

These configurations can be customized via .withXXX() methods with no global context fallback:

Configuration	Method	Default	Description
Auto Create	.withAutoCreate(enabled)	true	Auto-create collections and indexes
WriteConcern	.withWriteConcern(concern)	MAJORITY with journal	Write acknowledgment level
ReadConcern	.withReadConcern(concern)	MAJORITY	Read isolation level
ReadPreference	.withReadPreference(pref)	PRIMARY	Server selection for reads
Audit Repository Name	.withAuditRepositoryName(name)	flamingockAuditLog	Collection name for audit entries
Lock Repository Name	.withLockRepositoryName(name)	flamingockLock	Collection name for distributed locks

Important: These default values are optimized for maximum consistency and should ideally be left unchanged. Override them only for testing purposes or exceptional cases.

Configuration example

Here's a comprehensive example showing the configuration:

// Create a MongoDB Target System
MongoDBSyncTargetSystem mongoDbSyncTargetSystem = new MongoDBSyncTargetSystem("mongodb", mongoClient, auditDatabase);
// Audit store configuration (mandatory via constructor)
var auditStore = MongoDBSyncAuditStore.from(mongoDbSyncTargetSystem)
    .withWriteConcern(WriteConcern.W1)         // Optional configuration
    .withReadPreference(ReadPreference.secondary());  // Optional configuration

// Register with Flamingock
Flamingock.builder()
    .setAuditStore(auditStore)
    .addTargetSystems(targetSystems...)
    .build();

Audit store configuration resolution:

• MongoDBSyncTargetSystem: Must be provided via from() method. Gets MongoClient and DatabaseName from the target system.
• WriteConcern: Uses explicit configuration instead of default
• ReadPreference: Uses explicit configuration instead of default

This architecture ensures explicit audit store configuration with no fallback dependencies.

Next steps

• Learn about Target systems
• 👉 See a full example project