Mobile Wallet Adapter

The Mobile Wallet Adapter (MWA) is a protocol designed to expose Solana wallet functionality—specifically authorization and transaction signing—to dapps. It is optimized for mobile environments (iOS and Android) but is compatible with desktop OSs.

Key goals include:

• Enabling a single mobile device to act as a universal wallet for transactions across different devices.
• Ensuring dapp transactions remain private and secure.
• Providing a one-time authorization mechanism for persistent dapp-to-wallet connections.
• Supporting both native dapps and web-based dapps (via mobile browsers) through standard web technologies.

The @solana-mobile/wallet-standard-mobile package is a plugin designed to register a @wallet-standard/wallet-standard implementation specifically for mobile environments.

By using this plugin, web applications running on mobile devices can interface with native wallet applications to:

1. Sign messages: Request the user to sign arbitrary messages via their native wallet.
2. Sign transactions: Request the user to sign Solana transactions.
3. Send transactions: If the native wallet supports it, the web app can trigger the sending of transactions directly through the wallet.

The @solana-mobile/mobile-wallet-adapter-protocol-web3js package is a convenience wrapper designed to bridge the gap between the Mobile Wallet Adapter (MWA) protocol and the standard @solana/web3.js library.

It allows you to use common @solana/web3.js primitives—specifically Transaction and Uint8Array—directly with the @solana-mobile/mobile-wallet-adapter-protocol. This simplifies the process of preparing transactions in a standard web3.js format and passing them through the MWA protocol to a mobile wallet.

Because Nostr relays do not notify subscribers when a counterparty disconnects, the dapp endpoint can explicitly send a SESSION_END message to notify the wallet that the session is terminating.

Wallet Endpoint Actions upon receiving SESSION_END:

• Immediately close the Nostr relay connection.
• End the MWA session cleanly.

SESSION_END Event Structure:

{
    "kind": 20012,
    "pubkey": "<dapp_nostr_pubkey>",
    "tags": [
        ["d", "<session_identifier>"],
        ["p", "<wallet_nostr_pubkey>"],
        ["msg", "SESSION_END"]
    ],
    "content": ""
}

Association is the ephemeral process of establishing a shared identifier between a dapp endpoint and a wallet endpoint. A new association must be performed every time a dapp seeks to connect to a wallet.

To perform an association, the dapp endpoint must generate an ephemeral EC keypair on the P-256 curve. The public keypoint $Q_a$ is encoded using the X9.62 format (0x04 || x || y), base64url-encoded, and used as the association_token.

The Mobile Wallet Adapter specification is currently designed for the Solana network, but it is architected to support other blockchain networks in the future. Support for additional chains would involve three primary modifications:

1. Association URIs: Using new schemes such as newchain-wallet:// instead of the current solana-wallet://.
2. RPC Method Parameters:
   • authorize: Utilizing a different set of chain identifiers.
   • get_capabilities: Expressing domain-specific capabilities relevant to the new chain.
   • sign_and_send_transactions: Using chain-specific shapes for the options object.

Specific implementation details for new chains will be provided via updates to the core specification or through accompanying extensions.

This package is a reference implementation of the Mobile Wallet Adapter specification in JavaScript.

• Use this package if: You are implementing the protocol itself or need to interact directly with the low-level specification to issue API calls like sign_messages.
• Use @solana-mobile/wallet-adapter-mobile instead if: You are simply looking to integrate a standard JavaScript application (like a dApp) with mobile wallets. The latter provides a higher-level abstraction for common integration tasks.

Association is the process of establishing a shared identifier between a dapp endpoint and a wallet endpoint. This process is ephemeral and must be performed every time a dapp seeks to connect to a wallet.

To initiate association, the dapp endpoint must generate an ephemeral EC keypair on the P-256 curve. The public keypoint Qa is encoded using the X9.62 format (0x04 || x || y), base64url-encoded, and used as the association_token.

# No runnable code provided for the raw key generation logic, but the token format is:
# association_token = base64url(X9.62(Qa))