dcrd/docs

Table of Contents

1. About
2. Getting Started
   1. Installation
   2. Configuration
   3. Controlling and Querying dcrd via dcrctl
   4. Mining
3. Help
   1. Network Configuration
   2. Wallet
4. Contact
   1. Community
5. Developer Resources
   1. Code Contribution Guidelines
   2. JSON-RPC Reference
   3. Go Modules
   4. Module Hierarchy

1. About

dcrd is a full node Decred implementation written in Go, and is licensed under the copyfree ISC License.

This software is currently under active development. It is extremely stable and has been in production use since February 2016.

It also properly relays newly mined blocks, maintains a transaction pool, and relays individual transactions that have not yet made it into a block. It ensures all individual transactions admitted to the pool follow the rules required into the block chain and also includes the vast majority of the more strict checks which filter transactions based on miner requirements ("standard" transactions).

2. Getting Started

2.1 Installation

The first step is to install dcrd. The installation instructions can be found here.

2.2 Configuration

dcrd has a number of configuration options, which can be viewed by running: $ dcrd --help.

2.3 Controlling and Querying dcrd via dcrctl

dcrctl is a command line utility that can be used to both control and query dcrd via RPC. dcrd does not enable its RPC server by default; You must configure at minimum both an RPC username and password or both an RPC limited username and password:

• dcrd.conf configuration file

[Application Options]
rpcuser=myuser
rpcpass=SomeDecentp4ssw0rd
rpclimituser=mylimituser
rpclimitpass=Limitedp4ssw0rd

• dcrctl.conf configuration file

[Application Options]
rpcuser=myuser
rpcpass=SomeDecentp4ssw0rd

OR

[Application Options]
rpclimituser=mylimituser
rpclimitpass=Limitedp4ssw0rd

For a list of available options, run: $ dcrctl --help

2.4 Mining
dcrd supports the getwork RPC. The limited user cannot access this RPC.

1. Add the payment addresses with the miningaddr option.

[Application Options]
rpcuser=myuser
rpcpass=SomeDecentp4ssw0rd
miningaddr=DsExampleAddress1
miningaddr=DsExampleAddress2

2. Add dcrd's RPC TLS certificate to system Certificate Authority list.

cgminer uses curl to fetch data from the RPC server. Since curl validates the certificate by default, we must install the dcrd RPC certificate into the default system Certificate Authority list.

Ubuntu

1. Copy rpc.cert to /usr/share/ca-certificates: # cp /home/user/.dcrd/rpc.cert /usr/share/ca-certificates/dcrd.crt
   
2. Add dcrd.crt to /etc/ca-certificates.conf: # echo dcrd.crt >> /etc/ca-certificates.conf
   
3. Update the CA certificate list: # update-ca-certificates
   

3. Set your mining software url to use https.

$ cgminer -o https://127.0.0.1:9109 -u rpcuser -p rpcpassword

3. Help

3.1 Network Configuration

• What Ports Are Used by Default?
• How To Listen on Specific Interfaces
• How To Configure RPC Server to Listen on Specific Interfaces
• Configuring dcrd with Tor

3.2 Wallet

dcrd was intentionally developed without an integrated wallet for security reasons. Please see dcrwallet for more information.

4. Contact

4.1 Community

If you have any further questions you can find us at:

https://decred.org/community

5. Developer Resources

5.1 Code Contribution Guidelines

• Code Contribution Guidelines

5.2 JSON-RPC Reference

• JSON-RPC Reference
• RPC Examples

5.3 Go Modules

The following versioned modules are provided by dcrd repository:

• rpcclient/v2 - Implements a robust and easy to use Websocket-enabled Decred JSON-RPC client
• dcrjson/v2 - Provides an extensive API for the underlying JSON-RPC command and return values
• wire - Implements the Decred wire protocol
• peer - Provides a common base for creating and managing Decred network peers
• blockchain - Implements Decred block handling and chain selection rules
  • stake - Provides an API for working with stake transactions and other portions related to the Proof-of-Stake (PoS) system
• txscript - Implements the Decred transaction scripting language
• dcrec - Provides constants for the supported cryptographic signatures supported by Decred scripts
  • secp256k1 - Implements the secp256k1 elliptic curve
  • edwards - Implements the edwards25519 twisted Edwards curve
• database - Provides a database interface for the Decred block chain
• mempool/v2 - Provides a policy-enforced pool of unmined Decred transactions
• dcrutil - Provides Decred-specific convenience functions and types
• chaincfg - Defines chain configuration parameters for the standard Decred networks and allows callers to define their own custom Decred networks for testing puproses
  • chainhash - Provides a generic hash type and associated functions that allows the specific hash algorithm to be abstracted
• certgen - Provides a function for creating a new TLS certificate key pair, typically used for encrypting RPC and websocket communications
• addrmgr - Provides a concurrency safe Decred network address manager
• connmgr - Implements a generic Decred network connection manager
• hdkeychain/v2 - Provides an API for working with Decred hierarchical deterministic extended keys
• gcs - Provides an API for building and using Golomb-coded set filters useful for light clients such as SPV wallets
• fees - Provides methods for tracking and estimating fee rates for new transactions to be mined into the network
• lru - Implements a generic concurrent safe least-recently-used cache with near O(1) perf

5.4 Module Hierarchy

The following diagram shows an overview of the hierarchy for the modules provided by the dcrd repository.