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ContextVM Documentation

Base Nostr Transport

Base Nostr Transport

Section titled “Base Nostr Transport”

The BaseNostrTransport is an abstract class that provides the core functionality for all Nostr-based transports in the @contextvm/sdk. It serves as the foundation for the NostrClientTransport and NostrServerTransport, handling the common logic for connecting to relays, managing subscriptions, and converting messages between the MCP and Nostr formats.

Core Responsibilities

Section titled “Core Responsibilities”

The BaseNostrTransport is responsible for:

  • Connection Management: Establishing and terminating connections to the Nostr relay network via a RelayHandler.
  • Event Serialization: Converting MCP JSON-RPC messages into Nostr events and vice-versa.
  • Cryptographic Operations: Signing Nostr events using a NostrSigner.
  • Message Publishing: Publishing events to the Nostr network.
  • Subscription Management: Creating and managing subscriptions to listen for relevant events.
  • Encryption Handling: Managing the encryption and decryption of messages based on the configured EncryptionMode.

BaseNostrTransportOptions

Section titled “BaseNostrTransportOptions”

When creating a transport that extends BaseNostrTransport, you must provide a configuration object that implements the BaseNostrTransportOptions interface:

export interface BaseNostrTransportOptions {
  signer: NostrSigner;
  relayHandler: RelayHandler;
  encryptionMode?: EncryptionMode;
}
  • signer: An instance of a NostrSigner for signing events. This is a required parameter.
  • relayHandler: An instance of a RelayHandler for managing relay connections. This is a required parameter.
  • encryptionMode: An optional EncryptionMode enum that determines the encryption policy for the transport. Defaults to OPTIONAL.

Key Methods

Section titled “Key Methods”

The BaseNostrTransport provides several protected methods that are used by its subclasses to implement their specific logic:

  • connect(): Connects to the configured Nostr relays.
  • disconnect(): Disconnects from the relays and clears subscriptions.
  • subscribe(filters, onEvent): Subscribes to Nostr events that match the given filters.
  • sendMcpMessage(...): Converts an MCP message to a Nostr event, signs it, optionally encrypts it, and publishes it to the network.
  • createSubscriptionFilters(...): A helper method to create standard filters for listening to messages directed at a specific public key.

How It Fits Together

Section titled “How It Fits Together”

The BaseNostrTransport encapsulates the shared logic of Nostr communication, allowing the NostrClientTransport and NostrServerTransport to focus on their specific roles in the client-server interaction model. By building on this common base, the SDK ensures consistent behavior and a unified approach to handling MCP over Nostr.

Next Steps

Section titled “Next Steps”

Now that you understand the foundation of the Nostr transports, let’s explore the concrete implementations: