DEXON

Official golang implementation of the DEXON fullnode.

DEXON implementation is based-on the go-ethereum project. The consensus layer is replaced with the DEXON consensus implementation.

Building the source

For prerequisites and detailed build instructions please read the Installation Instructions on the wiki.

Building gdex requires both a Go (version 1.10 or later) and a C compiler. You can install them using your favourite package manager. Once the dependencies are installed, run

make gdex

or, to build the full suite of utilities:

make all

Executables

The dexon project comes with several wrappers/executables found in the cmd directory.

Command	Description
gdex	Our main Ethereum CLI client. It is the entry point into the Ethereum network (main-, test- or private net), capable of running as a full node (default), archive node (retaining all historical state) or a light node (retrieving data live). It can be used by other processes as a gateway into the Ethereum network via JSON RPC endpoints exposed on top of HTTP, WebSocket and/or IPC transports. gdex --help.
nodekey	Utility to generate key pair for operating a node.
abigen	Source code generator to convert Ethereum contract definitions into easy to use, compile-time type-safe Go packages. It operates on plain Contract ABIs with expanded functionality if the contract bytecode is also available. However it also accepts Solidity source files, making development much more streamlined. Please see our Native DApps wiki page for details.
bootnode	Stripped down version of our Ethereum client implementation that only takes part in the network node discovery protocol, but does not run any of the higher level application protocols. It can be used as a lightweight bootstrap node to aid in finding peers in private networks.
evm	Developer utility version of the EVM (Ethereum Virtual Machine) that is capable of running bytecode snippets within a configurable environment and execution mode. Its purpose is to allow isolated, fine-grained debugging of EVM opcodes (e.g. evm --code 60ff60ff --debug).
rlpdump	Developer utility tool to convert binary RLP dumps (data encoding used by the DEXON protocol both network as well as consensus wise) to user friendlier hierarchical representation (e.g. rlpdump --hex CE0183FFFFFFC4C304050583616263).

Running gdex

Going through all the possible command line flags is out of scope here , but we've enumerated a few common parameter combos to get you up to speed quickly on how you can run your own Gdex instance.

Full node on the main DEXON network

By far the most common scenario is people wanting to simply interact with the DRXON network: create accounts; transfer funds; deploy and interact with contracts. For this particular use-case the user doesn't care about years-old historical data, so we can fast-sync quickly to the current state of the network. To do so:

$ gdex console

This command will:

• Start gdex in fast sync mode (default, can be changed with the --syncmode flag), causing it to download more data in exchange for avoiding processing the entire history of the Ethereum network, which is very CPU intensive.
• Start up Geth's built-in interactive JavaScript console JavaScript console, (via the trailing console subcommand) through which you can invoke all official web3 methods as well as Gdex's own management APIs This tool is optional and if you leave it out you can always attach to an already running Geth instance with gdex attach.

Full node on the DEXON test network

Transitioning towards developers, if you'd like to play around with creating DEXON contracts, you almost certainly would like to do that without any real money involved until you get the hang of the entire system. In other words, instead of attaching to the main network, you want to join the test network with your node, which is fully equivalent to the main network, but with play-DEX only.

$ gdex --testnet console

The console subcommand have the exact same meaning as above and they are equally useful on the testnet too. Please see above for their explanations if you've skipped to here.

Specifying the --testnet flag however will reconfigure your Gdex instance a bit:

• Instead of using the default data directory (~/.dexon on Linux for example), Gdex will nest itself one level deeper into a testnet subfolder (~/.dexon/testnet on Linux). Note, on OSX and Linux this also means that attaching to a running testnet node requires the use of a custom endpoint since gdex attach will try to attach to a production node endpoint by default. E.g. gdex attach <datadir>/testnet/gdex.ipc. Windows users are not affected by this.
• Instead of connecting the main DEXON network, the client will connect to the test network, which uses different P2P bootnodes, different network IDs and genesis states.

Note: Although there are some internal protective measures to prevent transactions from crossing over between the main network and test network, you should make sure to always use separate accounts for play-money and real-money. Unless you manually move accounts, Gdex will by default correctly separate the two networks and will not make any accounts available between them.

Configuration

As an alternative to passing the numerous flags to the gdex binary, you can also pass a configuration file via:

$ gdex --config /path/to/your_config.toml

To get an idea how the file should look like you can use the dumpconfig subcommand to export your existing configuration:

$ gdex --your-favourite-flags dumpconfig

Note: This works only with gdex v1.6.0 and above.

Docker quick start

One of the quickest ways to get DEXON up and running on your machine is by using Docker:

docker run -d --name dexon-node -v /Users/bob/dexon:/root \
           -p 8545:8545 -p 30303:30303 \
           dexonfoundation/dexon

This will start gdex in fast-sync mode with a DB memory allowance of 1GB just as the above command does. It will also create a persistent volume in your home directory for saving your blockchain as well as map the default ports. There is also an alpine tag available for a slim version of the image.

Do not forget --rpcaddr 0.0.0.0, if you want to access RPC from other containers and/or hosts. By default, gdex binds to the local interface and RPC endpoints is not accessible from the outside. -->

Programatically interfacing Gdex nodes

As a developer, sooner rather than later you'll want to start interacting with Gdex and the DEXON network via your own programs and not manually through the console. To aid this, Gdex has built-in support for a JSON-RPC based APIs which are ethereum-compatible (standard APIs and Gdex specific APIs). These can be exposed via HTTP, WebSockets and IPC (unix sockets on unix based platforms, and named pipes on Windows).

The IPC interface is enabled by default and exposes all the APIs supported by Gdex, whereas the HTTP and WS interfaces need to manually be enabled and only expose a subset of APIs due to security reasons. These can be turned on/off and configured as you'd expect.

HTTP based JSON-RPC API options:

• --rpc Enable the HTTP-RPC server
• --rpcaddr HTTP-RPC server listening interface (default: "localhost")
• --rpcport HTTP-RPC server listening port (default: 8545)
• --rpcapi API's offered over the HTTP-RPC interface (default: "eth,net,web3")
• --rpccorsdomain Comma separated list of domains from which to accept cross origin requests (browser enforced)
• --ws Enable the WS-RPC server
• --wsaddr WS-RPC server listening interface (default: "localhost")
• --wsport WS-RPC server listening port (default: 8546)
• --wsapi API's offered over the WS-RPC interface (default: "eth,net,web3")
• --wsorigins Origins from which to accept websockets requests
• --ipcdisable Disable the IPC-RPC server
• --ipcapi API's offered over the IPC-RPC interface (default: "admin,debug,eth,miner,net,personal,shh,txpool,web3")
• --ipcpath Filename for IPC socket/pipe within the datadir (explicit paths escape it)

You'll need to use your own programming environments' capabilities (libraries, tools, etc) to connect via HTTP, WS or IPC to a Geth node configured with the above flags and you'll need to speak JSON-RPC on all transports. You can reuse the same connection for multiple requests!

Note: Please understand the security implications of opening up an HTTP/WS based transport before doing so! Hackers on the internet are actively trying to subvert Ethereum nodes with exposed APIs! Further, all browser tabs can access locally running webservers, so malicious webpages could try to subvert locally available APIs!

Contribution

Thank you for considering to help out with the source code! We welcome contributions from anyone on the internet, and are grateful for even the smallest of fixes!

If you'd like to contribute to dexon, please fork, fix, commit and send a pull request for the maintainers to review and merge into the main code base. If you wish to submit more complex changes though, please check up with the core devs first on our gitter channel to ensure those changes are in line with the general philosophy of the project and/or get some early feedback which can make both your efforts much lighter as well as our review and merge procedures quick and simple.

Please make sure your contributions adhere to our coding guidelines:

• Code must adhere to the official Go formatting guidelines (i.e. uses gofmt).
• Code must be documented adhering to the official Go commentary guidelines.
• Pull requests need to be based on and opened against the dev branch.
• Commit messages should be prefixed with the package(s) they modify.
  • E.g. "eth, rpc: make trace configs optional"

Please see the Developers' Guide for more details on configuring your environment, managing project dependencies and testing procedures.

License

The dexon repository is forked from ethereum/go-ethereum, thus it inherit the licensing terms from upstream go-ethereum license:

The dexon library (i.e. all code outside of the cmd directory) is licensed under the GNU Lesser General Public License v3.0, also included in our repository in the COPYING.LESSER file.

The dexon binaries (i.e. all code inside of the cmd directory) is licensed under the GNU General Public License v3.0, also included in our repository in the COPYING file.