github.com/avence12/go-ethereum@v1.5.10-0.20170320123548-1dfd65f6d047/README.md (about) 1 ## Ethereum Go 2 3 Official golang implementation of the Ethereum protocol. 4 5 [![API Reference]( 6 https://camo.githubusercontent.com/915b7be44ada53c290eb157634330494ebe3e30a/68747470733a2f2f676f646f632e6f72672f6769746875622e636f6d2f676f6c616e672f6764646f3f7374617475732e737667 7 )](https://godoc.org/github.com/ethereum/go-ethereum) 8 [![Gitter](https://badges.gitter.im/Join%20Chat.svg)](https://gitter.im/ethereum/go-ethereum?utm_source=badge&utm_medium=badge&utm_campaign=pr-badge) 9 10 Automated builds are available for stable releases and the unstable master branch. 11 Binary archives are published at https://geth.ethereum.org/downloads/. 12 13 ## Building the source 14 15 For prerequisites and detailed build instructions please read the 16 [Installation Instructions](https://github.com/ethereum/go-ethereum/wiki/Building-Ethereum) 17 on the wiki. 18 19 Building geth requires both a Go and a C compiler. 20 You can install them using your favourite package manager. 21 Once the dependencies are installed, run 22 23 make geth 24 25 or, to build the full suite of utilities: 26 27 make all 28 29 ## Executables 30 31 The go-ethereum project comes with several wrappers/executables found in the `cmd` directory. 32 33 | Command | Description | 34 |:----------:|-------------| 35 | **`geth`** | 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. `geth --help` and the [CLI Wiki page](https://github.com/ethereum/go-ethereum/wiki/Command-Line-Options) for command line options | 36 | `abigen` | Source code generator to convert Ethereum contract definitions into easy to use, compile-time type-safe Go packages. It operates on plain [Ethereum contract ABIs](https://github.com/ethereum/wiki/wiki/Ethereum-Contract-ABI) 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](https://github.com/ethereum/go-ethereum/wiki/Native-DApps:-Go-bindings-to-Ethereum-contracts) wiki page for details. | 37 | `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. | 38 | `disasm` | Bytecode disassembler to convert EVM (Ethereum Virtual Machine) bytecode into more user friendly assembly-like opcodes (e.g. `echo "6001" | disasm`). For details on the individual opcodes, please see pages 22-30 of the [Ethereum Yellow Paper](http://gavwood.com/paper.pdf). | 39 | `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 insolated, fine-grained debugging of EVM opcodes (e.g. `evm --code 60ff60ff --debug`). | 40 | `gethrpctest` | Developer utility tool to support our [ethereum/rpc-test](https://github.com/ethereum/rpc-tests) test suite which validates baseline conformity to the [Ethereum JSON RPC](https://github.com/ethereum/wiki/wiki/JSON-RPC) specs. Please see the [test suite's readme](https://github.com/ethereum/rpc-tests/blob/master/README.md) for details. | 41 | `rlpdump` | Developer utility tool to convert binary RLP ([Recursive Length Prefix](https://github.com/ethereum/wiki/wiki/RLP)) dumps (data encoding used by the Ethereum protocol both network as well as consensus wise) to user friendlier hierarchical representation (e.g. `rlpdump --hex CE0183FFFFFFC4C304050583616263`). | 42 | `swarm` | swarm daemon and tools. This is the entrypoint for the swarm network. `swarm --help` for command line options and subcommands. See https://swarm-guide.readthedocs.io for swarm documentation. | 43 44 ## Running geth 45 46 Going through all the possible command line flags is out of scope here (please consult our 47 [CLI Wiki page](https://github.com/ethereum/go-ethereum/wiki/Command-Line-Options)), but we've 48 enumerated a few common parameter combos to get you up to speed quickly on how you can run your 49 own Geth instance. 50 51 ### Full node on the main Ethereum network 52 53 By far the most common scenario is people wanting to simply interact with the Ethereum network: 54 create accounts; transfer funds; deploy and interact with contracts. For this particular use-case 55 the user doesn't care about years-old historical data, so we can fast-sync quickly to the current 56 state of the network. To do so: 57 58 ``` 59 $ geth --fast --cache=512 console 60 ``` 61 62 This command will: 63 64 * Start geth in fast sync mode (`--fast`), causing it to download more data in exchange for avoiding 65 processing the entire history of the Ethereum network, which is very CPU intensive. 66 * Bump the memory allowance of the database to 512MB (`--cache=512`), which can help significantly in 67 sync times especially for HDD users. This flag is optional and you can set it as high or as low as 68 you'd like, though we'd recommend the 512MB - 2GB range. 69 * Start up Geth's built-in interactive [JavaScript console](https://github.com/ethereum/go-ethereum/wiki/JavaScript-Console), 70 (via the trailing `console` subcommand) through which you can invoke all official [`web3` methods](https://github.com/ethereum/wiki/wiki/JavaScript-API) 71 as well as Geth's own [management APIs](https://github.com/ethereum/go-ethereum/wiki/Management-APIs). 72 This too is optional and if you leave it out you can always attach to an already running Geth instance 73 with `geth --attach`. 74 75 ### Full node on the Ethereum test network 76 77 Transitioning towards developers, if you'd like to play around with creating Ethereum contracts, you 78 almost certainly would like to do that without any real money involved until you get the hang of the 79 entire system. In other words, instead of attaching to the main network, you want to join the **test** 80 network with your node, which is fully equivalent to the main network, but with play-Ether only. 81 82 ``` 83 $ geth --testnet --fast --cache=512 console 84 ``` 85 86 The `--fast`, `--cache` flags and `console` subcommand have the exact same meaning as above and they 87 are equially useful on the testnet too. Please see above for their explanations if you've skipped to 88 here. 89 90 Specifying the `--testnet` flag however will reconfigure your Geth instance a bit: 91 92 * Instead of using the default data directory (`~/.ethereum` on Linux for example), Geth will nest 93 itself one level deeper into a `testnet` subfolder (`~/.ethereum/testnet` on Linux). 94 * Instead of connecting the main Ethereum network, the client will connect to the test network, 95 which uses different P2P bootnodes, different network IDs and genesis states. 96 97 *Note: Although there are some internal protective measures to prevent transactions from crossing 98 over between the main network and test network (different starting nonces), you should make sure to 99 always use separate accounts for play-money and real-money. Unless you manually move accounts, Geth 100 will by default correctly separate the two networks and will not make any accounts available between 101 them.* 102 103 #### Docker quick start 104 105 One of the quickest ways to get Ethereum up and running on your machine is by using Docker: 106 107 ``` 108 docker run -d --name ethereum-node -v /Users/alice/ethereum:/root \ 109 -p 8545:8545 -p 30303:30303 \ 110 ethereum/client-go --fast --cache=512 111 ``` 112 113 This will start geth in fast sync mode with a DB memory allowance of 512MB 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. 114 115 ### Programatically interfacing Geth nodes 116 117 As a developer, sooner rather than later you'll want to start interacting with Geth and the Ethereum 118 network via your own programs and not manually through the console. To aid this, Geth has built in 119 support for a JSON-RPC based APIs ([standard APIs](https://github.com/ethereum/wiki/wiki/JSON-RPC) and 120 [Geth specific APIs](https://github.com/ethereum/go-ethereum/wiki/Management-APIs)). These can be 121 exposed via HTTP, WebSockets and IPC (unix sockets on unix based platforms, and named pipes on Windows). 122 123 The IPC interface is enabled by default and exposes all the APIs supported by Geth, whereas the HTTP 124 and WS interfaces need to manually be enabled and only expose a subset of APIs due to security reasons. 125 These can be turned on/off and configured as you'd expect. 126 127 HTTP based JSON-RPC API options: 128 129 * `--rpc` Enable the HTTP-RPC server 130 * `--rpcaddr` HTTP-RPC server listening interface (default: "localhost") 131 * `--rpcport` HTTP-RPC server listening port (default: 8545) 132 * `--rpcapi` API's offered over the HTTP-RPC interface (default: "eth,net,web3") 133 * `--rpccorsdomain` Comma separated list of domains from which to accept cross origin requests (browser enforced) 134 * `--ws` Enable the WS-RPC server 135 * `--wsaddr` WS-RPC server listening interface (default: "localhost") 136 * `--wsport` WS-RPC server listening port (default: 8546) 137 * `--wsapi` API's offered over the WS-RPC interface (default: "eth,net,web3") 138 * `--wsorigins` Origins from which to accept websockets requests 139 * `--ipcdisable` Disable the IPC-RPC server 140 * `--ipcapi` API's offered over the IPC-RPC interface (default: "admin,debug,eth,miner,net,personal,shh,txpool,web3") 141 * `--ipcpath` Filename for IPC socket/pipe within the datadir (explicit paths escape it) 142 143 You'll need to use your own programming environments' capabilities (libraries, tools, etc) to connect 144 via HTTP, WS or IPC to a Geth node configured with the above flags and you'll need to speak [JSON-RPC](http://www.jsonrpc.org/specification) 145 on all transports. You can reuse the same connection for multiple requests! 146 147 **Note: Please understand the security implications of opening up an HTTP/WS based transport before 148 doing so! Hackers on the internet are actively trying to subvert Ethereum nodes with exposed APIs! 149 Further, all browser tabs can access locally running webservers, so malicious webpages could try to 150 subvert locally available APIs!** 151 152 ### Operating a private network 153 154 Maintaining your own private network is more involved as a lot of configurations taken for granted in 155 the official networks need to be manually set up. 156 157 #### Defining the private genesis state 158 159 First, you'll need to create the genesis state of your networks, which all nodes need to be aware of 160 and agree upon. This consists of a small JSON file (e.g. call it `genesis.json`): 161 162 ```json 163 { 164 "alloc" : {}, 165 "coinbase" : "0x0000000000000000000000000000000000000000", 166 "difficulty" : "0x20000", 167 "extraData" : "", 168 "gasLimit" : "0x2fefd8", 169 "nonce" : "0x0000000000000042", 170 "mixhash" : "0x0000000000000000000000000000000000000000000000000000000000000000", 171 "parentHash" : "0x0000000000000000000000000000000000000000000000000000000000000000", 172 "timestamp" : "0x00" 173 } 174 ``` 175 176 The above fields should be fine for most purposes, although we'd recommend changing the `nonce` to 177 some random value so you prevent unknown remote nodes from being able to connect to you. If you'd 178 like to pre-fund some accounts for easier testing, you can populate the `alloc` field with account 179 configs: 180 181 ```json 182 "alloc": { 183 "0x0000000000000000000000000000000000000001": {"balance": "111111111"}, 184 "0x0000000000000000000000000000000000000002": {"balance": "222222222"} 185 } 186 ``` 187 188 With the genesis state defined in the above JSON file, you'll need to initialize **every** Geth node 189 with it prior to starting it up to ensure all blockchain parameters are correctly set: 190 191 ``` 192 $ geth init path/to/genesis.json 193 ``` 194 195 #### Creating the rendezvous point 196 197 With all nodes that you want to run initialized to the desired genesis state, you'll need to start a 198 bootstrap node that others can use to find each other in your network and/or over the internet. The 199 clean way is to configure and run a dedicated bootnode: 200 201 ``` 202 $ bootnode --genkey=boot.key 203 $ bootnode --nodekey=boot.key 204 ``` 205 206 With the bootnode online, it will display an [`enode` URL](https://github.com/ethereum/wiki/wiki/enode-url-format) 207 that other nodes can use to connect to it and exchange peer information. Make sure to replace the 208 displayed IP address information (most probably `[::]`) with your externally accessible IP to get the 209 actual `enode` URL. 210 211 *Note: You could also use a full fledged Geth node as a bootnode, but it's the less recommended way.* 212 213 #### Starting up your member nodes 214 215 With the bootnode operational and externally reachable (you can try `telnet <ip> <port>` to ensure 216 it's indeed reachable), start every subsequent Geth node pointed to the bootnode for peer discovery 217 via the `--bootnodes` flag. It will probably also be desirable to keep the data directory of your 218 private network separated, so do also specify a custom `--datadir` flag. 219 220 ``` 221 $ geth --datadir=path/to/custom/data/folder --bootnodes=<bootnode-enode-url-from-above> 222 ``` 223 224 *Note: Since your network will be completely cut off from the main and test networks, you'll also 225 need to configure a miner to process transactions and create new blocks for you.* 226 227 #### Running a private miner 228 229 Mining on the public Ethereum network is a complex task as it's only feasible using GPUs, requiring 230 an OpenCL or CUDA enabled `ethminer` instance. For information on such a setup, please consult the 231 [EtherMining subreddit](https://www.reddit.com/r/EtherMining/) and the [Genoil miner](https://github.com/Genoil/cpp-ethereum) 232 repository. 233 234 In a private network setting however, a single CPU miner instance is more than enough for practical 235 purposes as it can produce a stable stream of blocks at the correct intervals without needing heavy 236 resources (consider running on a single thread, no need for multiple ones either). To start a Geth 237 instance for mining, run it with all your usual flags, extended by: 238 239 ``` 240 $ geth <usual-flags> --mine --minerthreads=1 --etherbase=0x0000000000000000000000000000000000000000 241 ``` 242 243 Which will start mining bocks and transactions on a single CPU thread, crediting all proceedings to 244 the account specified by `--etherbase`. You can further tune the mining by changing the default gas 245 limit blocks converge to (`--targetgaslimit`) and the price transactions are accepted at (`--gasprice`). 246 247 ## Contribution 248 249 Thank you for considering to help out with the source code! We welcome contributions from 250 anyone on the internet, and are grateful for even the smallest of fixes! 251 252 If you'd like to contribute to go-ethereum, please fork, fix, commit and send a pull request 253 for the maintainers to review and merge into the main code base. If you wish to submit more 254 complex changes though, please check up with the core devs first on [our gitter channel](https://gitter.im/ethereum/go-ethereum) 255 to ensure those changes are in line with the general philosophy of the project and/or get some 256 early feedback which can make both your efforts much lighter as well as our review and merge 257 procedures quick and simple. 258 259 Please make sure your contributions adhere to our coding guidelines: 260 261 * Code must adhere to the official Go [formatting](https://golang.org/doc/effective_go.html#formatting) guidelines (i.e. uses [gofmt](https://golang.org/cmd/gofmt/)). 262 * Code must be documented adhering to the official Go [commentary](https://golang.org/doc/effective_go.html#commentary) guidelines. 263 * Pull requests need to be based on and opened against the `master` branch. 264 * Commit messages should be prefixed with the package(s) they modify. 265 * E.g. "eth, rpc: make trace configs optional" 266 267 Please see the [Developers' Guide](https://github.com/ethereum/go-ethereum/wiki/Developers'-Guide) 268 for more details on configuring your environment, managing project dependencies and testing procedures. 269 270 ## License 271 272 The go-ethereum library (i.e. all code outside of the `cmd` directory) is licensed under the 273 [GNU Lesser General Public License v3.0](https://www.gnu.org/licenses/lgpl-3.0.en.html), also 274 included in our repository in the `COPYING.LESSER` file. 275 276 The go-ethereum binaries (i.e. all code inside of the `cmd` directory) is licensed under the 277 [GNU General Public License v3.0](https://www.gnu.org/licenses/gpl-3.0.en.html), also included 278 in our repository in the `COPYING` file.