Akka.Persistence.RavenDB

Akka.Persistence.RavenDB is a persistence plugin for Akka.NET that integrates RavenDB as a durable storage backend.
It allows persisting journal events and snapshots of your Akka.NET actors to a RavenDB database.
Querying is supported through the Akka.Persistence query interface, with RavenDB serving as the underlying storage engine.

Configuration

To activate and use the Akka.Persistence.RavenDB plugin, you have the following configuration options:

• Configure using Akka.Hosting (the easy way)
• Configure directly in your actor system configuration file using HOCON (the classic way).

Note:
When configuring the plugin using both Akka.Hosting and HOCON, in cases where parameters overlap,
the configuration provided via Akka.Hosting take precedence and will override the corresponding HOCON settings.

Configure with Akka.Hosting

Using Akka.Hosting, you can easily set up the plugin within your application's startup configuration.
Here is a basic example:

using Akka.Hosting;
using Akka.Persistence;
using Akka.Persistence.Hosting;
using Akka.Persistence.RavenDb.Hosting;

var host = new HostBuilder().ConfigureServices((context, services) => {
    services.AddAkka("my-actor-system-name", (builder, provider) =>
    {
        builder.WithRavenDbPersistence(
            urls: new[] { "http://localhost:8080" },
            databaseName: "AkkaStorage");
    });
})
    
var app = builder.Build();
app.Run();

Configure with HOCON

While both the journal and snapshot-store have the same configuration keys, they reside in separate scopes.
So when configuring using HOCON, the settings for the journal and snapshot-store must be provided separately.
For example, properties urls and name can have the same values for both stores, but they still need to be defined distinctly within their respective sections.

akka.persistence {
    # Setup the RavenDB journal store:
    journal {
        plugin = "akka.persistence.journal.ravendb"
        ravendb {
            # Qualified type name of the RavenDB persistence journal actor
            class = "Akka.Persistence.RavenDb.Journal.RavenDbJournal, Akka.Persistence.RavenDb" 

            # Dispatcher used to drive journal actor
            plugin-dispatcher = "akka.actor.default-dispatcher"

            # URLs to the RavenDB cluster
            urls = ["http://localhost:8080"]
            
            # Database name where journal events will be stored
            name = "AkkaStorage"
            
            # Create the database if it doesn't exist
            auto-initialize = false

            # Location of a client certificate to access a secure RavenDB database.
            # If a password is required, it should be stored in the `RAVEN_CERTIFICATE_PASSWORD` env variable.
            #certificate-path = "\\path\\to\\cert.pfx"

            # Timeout for 'save' requests sent to RavenDB, such as writing or deleting
            # as opposed to stream operations which may take longer and have a different timeout (12h).
            # Client will fail requests that take longer than this.
            # default: 30s
            #save-changes-timeout = 30s

            # Http version for the RavenDB client to use in communication with the server
            # default: 2.0
            #http-version = "2.0"

            # Determines whether to compress the data sent in the client-server TCP communication
            # default: false
            #disable-tcp-compression = false
        }
    }
    
    # Setup the RavenDB snapshot store:
    snapshot-store {
        plugin = "akka.persistence.snapshot-store.ravendb"
        ravendb {
            # Qualified type name of the RavenDB persistence snapshot actor
            class = "Akka.Persistence.RavenDb.Snapshot.RavenDbSnapshotStore, Akka.Persistence.RavenDb"

            # Dispatcher used to drive snapshot storage actor
            plugin-dispatcher = "akka.actor.default-dispatcher"

            # URLs to the RavenDB cluster
            urls = ["http://localhost:8080"]
            
            # Database name where snapshots will be stored
            name = "AkkaStorage"
            
            # Create the database if it doesn't exist
            auto-initialize = false

            # Location of a client certificate to access a secure RavenDB database.
            # If a password is required, it should be stored in the `RAVEN_CERTIFICATE_PASSWORD` env variable.
            #certificate-path = "\\path\\to\\cert.pfx"

            # Timeout for 'save' requests sent to RavenDB, such as writing or deleting
            # as opposed to stream operations which may take longer and have a different timeout (12h).
            # Client will fail requests that take longer than this.
            # default: 30s
            #save-changes-timeout = 30s

            # Http version for the RavenDB client to use in communication with the server
            # default: 2.0
            #http-version = "2.0"

            # Determines whether to compress the data sent in the client-server TCP communication
            # default: false
            #disable-tcp-compression = false
        }
    }
    
    query {
        # Configure RavenDB as the underlying storage engine for querying:
        ravendb {
            # Implementation class of the EventStore ReadJournalProvider
            class = "Akka.Persistence.RavenDb.Query.RavenDbReadJournalProvider, Akka.Persistence.RavenDb"

            # The interval at which to check for new ids/events
            # default: 3s
            #refresh-interval = 3s
  
            # The number of events to keep buffered while querying until they are delivered downstream.
            # default: 65536
            #max-buffer-size = 65536
        }
    }
}