Developer Environment

To develop Dogecoin applications to be deployed on ICP, your local developer environment will need to include:

• A local Dogecoin regtest node.

• The Rust toolchain for installing Rust crates and compiling Rust code.

• The IC SDK for creating, deploying, and managing canisters. You can install it natively on macOS and Linux; however, Windows users will need to set up WSL 2 before installing the IC SDK.

The IC SDK includes the dfx command-line tool, which is used to manage canisters and interact with the Internet Computer network.

Interacting with Dogecoin requires dfx version 0.30.1-beta.0 or higher. You can check your installed version by running:

dfx --version

To install and switch to a specific dfx version, use:

dfxvm install <version>
dfxvm default <version>

Create a local Dogecoin network (regtest) with dogecoind

It is recommended to set up a local Dogecoin regtest network to mine blocks quickly and at will, which facilitates testing various cases without having to rely on the Dogecoin mainnet where blocks are produced every minute on average.

• Step 1: Download Dogecoin Core.

Example for a Linux machine:

# Download the binary
curl -L -O https://github.com/dogecoin/dogecoin/releases/download/v1.14.9/dogecoin-1.14.9-x86_64-linux-gnu.tar.gz

# Unpack
tar -xvf dogecoin-1.14.9-x86_64-linux-gnu.tar.gz

# Add binaries to the PATH environment variable
export PATH="$(pwd)/dogecoin-1.14.9/bin:$PATH"

• Step 2: Create a subdirectory for Dogecoin data.

This should be created in the project folder root. This allows you to run different local Dogecoin regtest networks for different projects.

mkdir dogecoin_data

• Step 3: Create a file called dogecoin.conf.

cat > dogecoin_data/dogecoin.conf <<EOF
regtest=1
txindex=1
rpcuser=ic-doge-integration
rpcpassword=QPQiNaph19FqUsCrBRN0FII7lyM26B51fAMeBQzCb-E=
rpcauth=ic-doge-integration:cdf2741387f3a12438f69092f0fdad8e\$62081498c98bee09a0dce2b30671123fa561932992ce377585e8e08bb0c11dfa
EOF

Explanation of settings:

• regtest=1: Enables Dogecoin’s regression test mode for local testing.

• txindex=1: Maintains a full transaction index to support lookups by transaction ID.

• rpcuser=ic-doge-integration: Sets a default username for JSON-RPC authentication.

• rpcpassword=QPQ…b-E=: Sets the password for JSON-RPC authentication.

• rpcauth=ic-doge-integration:cdf…dfa: Uses an alternative authentication method for RPC, combining the username and a salted hash.

Find more details about the dogecoin.conf settings in the Dogecoin Core Daemon documentation.

• Step 4: Run dogecoind to start the Dogecoin client.

dogecoind -datadir=$(pwd)/dogecoin_data -printtoconsole --port=18444 

This command assumes that port 18444 on your machine is available. If it isn't, change the specified port accordingly.

Starting dfx with Dogecoin support

To deploy and test projects locally, first start dfx in your local development environment with Dogecoin support enabled.

dfx start --enable-dogecoin

dfx will run a local instance of the Dogecoin API deployed as a canister for your application to interact with. The --enable-dogecoin flag uses the default Dogecoin node configuration, 127.0.0.1:18444. This address and port can be manually configured with the --dogecoin-node flag:

dfx start --enable-dogecoin --dogecoin-node <host_address>:<port>

Configuring the local Dogecoin API

The Dogecoin API can be configured either using the command line option --dogecoin-node provided to dfx or by modifying the project’s dfx.json file.

If both command line options and dfx.json configurations are provided, the command line option takes precedence.

The Dogecoin API configuration is specified under the defaults section of the dfx.json file. Below is an example configuration:

{
  "defaults": {
    "dogecoin": {
      "enabled": true,
      "nodes": ["127.0.0.1:18444"]
    }
  }
}

The Dogecoin configuration in dfx.json adds fields under defaults as shown above. This configuration won't actually have any effect unless dfx.json also defines the local IC network, and dfx start is run within the project directory. An example of a full configuration, including the local IC network definition, can be found in the dfx.json file of the basic_dogecoin example project.

Configuration options

• enabled (boolean): Determines whether the Dogecoin adapter is enabled. Default: false.

• nodes (array of strings or null): Lists node addresses to connect to. Most likely, you may want to set this to the default IP and port of dogecoind, 127.0.0.1:18444. Default: null.

• canister_init_arg (string): Optional initialization arguments for the Dogecoin canister. It sets up initial configuration parameters like stability threshold, network type, block sources, fees, syncing state, API access, and more. Details about these parameters can be found in the Dogecoin canister interface specification. By default, the local Dogecoin API mirrors the settings used in the production environment. You can view these settings by searching for the Dogecoin canister on the ICP Dashboard and calling its get_config endpoint.