Monero C++ Library

A C++ library for creating Haven applications.

• Supports fully client-side wallets by wrapping wallet2.h.
• Supports multisig, view-only, and offline wallets.
• Uses a clearly defined data model and API specification intended to be intuitive and robust.
• Query wallet transactions, transfers, and outputs by their properties.
• Receive notifications when wallets sync, send, or receive.
• Tested by over 100 tests in monero-java and monero-javascript using JNI and WebAssembly bindings.

Table of contents

• Sample code
• Using this library in your project
• Developer guide
• See also
• License
• Donations

Sample code

This code introduces the API. See the documentation or specification PDF for more details.

Note: This API might change depending on feedback, such as changing structs to classes, using pure object-oriented accessors and mutators, not using boost::optional with shared_ptrs, etc. Feedback is welcome.

// create a wallet from a mnemonic phrase
string mnemonic = "hefty value later extra artistic firm radar yodel talent future fungal nutshell because sanity awesome nail unjustly rage unafraid cedar delayed thumbs comb custom sanity";
monero_wallet* wallet_restored = monero_wallet_core::create_wallet_from_mnemonic(
    "MyWalletRestored",                   // wallet path and name
    "supersecretpassword123",             // wallet password
    monero_network_type::STAGENET,        // network type
    mnemonic,                             // mnemonic phrase
    monero_rpc_connection(                // daemon connection
        string("http://localhost:38081"),
        string("superuser"),
        string("abctesting123")),
    380104,                               // restore height
    ""                                    // seed offset
);

// synchronize the wallet and receive progress notifications
struct : monero_wallet_listener {
  void on_sync_progress(uint64_t height, uint64_t start_height, uint64_t end_height, double percent_done, const string& message) {
    // feed a progress bar?
  }
} my_sync_listener;
wallet_restored->sync(my_sync_listener);

// start syncing the wallet continuously in the background
wallet_restored->start_syncing();

// get balance, account, subaddresses
string restored_primary = wallet_restored->get_primary_address();
uint64_t balance = wallet_restored->get_balance();    // can specify account and subaddress indices
monero_account account = wallet_restored->get_account(1, true);       // get account with subaddresses
uint64_t unlocked_account_balance = account.m_unlocked_balance.get(); // get boost::optional value

// query a transaction by hash
monero_tx_query tx_query;
tx_query.m_hash = "314a0f1375db31cea4dac4e0a51514a6282b43792269b3660166d4d2b46437ca";
shared_ptr<monero_tx_wallet> tx = wallet_restored->get_txs(tx_query)[0];
for (const shared_ptr<monero_transfer> transfer : tx->get_transfers()) {
  bool is_incoming = transfer->is_incoming().get();
  uint64_t in_amount = transfer->m_amount.get();
  int account_index = transfer->m_account_index.get();
}

// query incoming transfers to account 1
monero_transfer_query transfer_query;
transfer_query.m_is_incoming = true;
transfer_query.m_account_index = 1;
vector<shared_ptr<monero_transfer>> transfers = wallet_restored->get_transfers(transfer_query);

// query unspent outputs
monero_output_query output_query;
output_query.m_is_spent = false;
vector<shared_ptr<monero_output_wallet>> outputs = wallet_restored->get_outputs(output_query);

// create and sync a new wallet with a random mnemonic phrase
monero_wallet* wallet_random = monero_wallet_core::create_wallet_random(
    "MyWalletRandom",                     // wallet path and name
    "supersecretpassword123",             // wallet password
    monero_network_type::STAGENET,        // network type
    monero_rpc_connection(                // daemon connection
        string("http://localhost:38081"),
        string("superuser"),
        string("abctesting123")),
    "English");
wallet_random->sync();

// continuously synchronize the wallet in the background
wallet_random->start_syncing();

// get wallet info
string random_mnemonic = wallet_random->get_mnemonic();
string random_primary = wallet_random->get_primary_address();
uint64_t random_height = wallet_random->get_height();
bool random_is_synced = wallet_random->is_synced();

// receive notifications when the wallet receives funds
struct : monero_wallet_listener {
  void on_output_received(const monero_output_wallet& output) {
    cout << "Wallet received funds!" << endl;
    string tx_hash = output.m_tx->m_hash.get();
    int account_index = output.m_account_index.get();
    int subaddress_index = output.m_subaddress_index.get();
    OUTPUT_RECEIVED = true;
  }
} my_listener;
wallet_random->add_listener(my_listener);

// send funds from the restored wallet to the random wallet
monero_tx_config config;
config.m_account_index = 0;
config.m_address = wallet_random->get_address(1, 0);
config.m_amount = 50000;
config.m_relay = true;
shared_ptr<monero_tx_wallet> sent_tx = wallet_restored->create_tx(config);
bool in_pool = sent_tx->m_in_tx_pool.get();  // true

// mine with 7 threads to push the network along
int num_threads = 7;
bool is_background = false;
bool ignore_battery = false;
wallet_restored->start_mining(num_threads, is_background, ignore_battery);

// wait for the next block to be added to the chain
uint64_t next_height = wallet_random->wait_for_next_block();

// stop mining
wallet_restored->stop_mining();

// create config to send funds to multiple destinations in the random wallet
config = monero_tx_config();
config.m_account_index = 1;                // withdraw funds from this account
config.m_subaddress_indices = vector<uint32_t>();
config.m_subaddress_indices.push_back(0);
config.m_subaddress_indices.push_back(1);  // withdraw funds from these subaddresses within the account
config.m_priority = monero_tx_priority::UNIMPORTANT;  // no rush
config.m_relay = false;  // create transaction and relay to the network if true
vector<shared_ptr<monero_destination>> destinations;  // specify the recipients and their amounts
destinations.push_back(make_shared<monero_destination>(wallet_random->get_address(1, 0), 50000));
destinations.push_back(make_shared<monero_destination>(wallet_random->get_address(2, 0), 50000));
config.m_destinations = destinations;

// create the transaction, confirm with the user, and relay to the network
shared_ptr<monero_tx_wallet> created_tx = wallet_restored->create_tx(config);
uint64_t fee = created_tx->m_fee.get(); // "Are you sure you want to send ...?"
wallet_restored->relay_tx(*created_tx); // recipient receives notification within 10 seconds

// save and close the wallets
wallet_restored->close(true);
wallet_random->close(true);

Using this library in your project

This project may be compiled as part of another application or built as a shared or static library.

For example, monero-java compiles this project to a shared library to support Java JNI bindings, while monero-javascript compiles this project to WebAssembly binaries.

1. Set up dependencies
   1. Set up Boost
      1. Download and extract the boost 1.72.0 source code zip from https://www.boost.org/users/download/ to ./external/boost-sdk/.
      2. cd ./external/boost-sdk/
      3. ./bootstrap.sh
      4. ./b2
   2. Set up OpenSSL
      1. Download and extract the OpenSSL 1.1.1 source code zip from https://github.com/openssl/openssl/tree/OpenSSL_1_1_1 to ./external/openssl-sdk/.
      2. Build for your system.
         Unix: ./config && make
   3. Set up hidapi
      1. Download the latest hidapi source code from https://github.com/signal11/hidapi.
      2. Build hidapi for your system.
         Mac requires autoreconf: brew install automake
      3. Copy libhidapi.a to ./external-libs/hidapi.
   4. Set up libsodium
      1. Build libsodium for your system.
      2. Copy libsodium.a to ./external-libs/libsodium.
         Mac: installed through homebrew at /usr/local/Cellar/libsodium/1.0.17/lib/libsodium.a
   5. Set up monero-project/monero:
      1. Update submodules: ./bin/update_submodules.sh
      2. cd ./external/monero-core
      3. Modify CMakeLists.txt: option(BUILD_GUI_DEPS "Build GUI dependencies." ON)
      4. Run twice to create libwallet_merged.a in addition to other .a libraries: make release-static -j8
2. Link to this library's source files in your application or build as a shared library in ./build/: ./bin/build_libmonero_cpp.sh

These build steps aspire to be automated further. Any help is greatly appreciated.

Developer guide

Refer to monero-javascript's developer guide which mostly translates to this C++ library.

See also

• API specification
• monero-java
• monero-javascript

License

This project is licensed under MIT.

Donations

If this library brings you value, please consider donating.

46FR1GKVqFNQnDiFkH7AuzbUBrGQwz2VdaXTDD4jcjRE8YkkoTYTmZ2Vohsz9gLSqkj5EM6ai9Q7sBoX4FPPYJdGKQQXPVz