README update

README.md

@@ -16,7 +16,88 @@
           [applications: [:exw3]]
         end
 
-# Compiling solidity
+## Overview
+
+ExW3 is a wrapper around ethereumex to provide a high level, and user friendly json rpc api. It currently only supports Http.
+
+## Usage
+
+Ensure you have an ethereum node to connect to at the specified url in your config. Any easy local testnet to use is ganache-cli:
+```
+ganache-cli
+```
+
+Make sure your config includes:
+```elixir
+config :ethereumex,
+  url: "http://localhost:8545"
+```
+
+Currently ExW3 supports a handful of json rpc commands. Mostly just the useful ones. If it doesn't support those specific commands you can always use the Ethereumex commands.
+
+```elixir
+iex(1)> accounts = ExW3.accounts()                                        
+["0x957e3d06f15d6fc3913a24c5c41009784a4ec683",
+ "0xa9a5037dc1cba71609792e3309b57e777ae01c0f",
+ "0x4944392f44d60f2f949ba241244401bd43863c1c",
+ "0xc0fe85ae40d6dd480ccbf31902bdb6b90057c908",
+ "0xc06f7379abb368c54059c78f9ef524d8badcb7da",
+ "0x0de579fe6dcd60620e10e1ce447dfb6077306e68",
+ "0x8895d7195659cbcb442825b62bb028176ab126f6",
+ "0x205b8d4b9b52e9653d9ea29815bfa2ccf9f11b71",
+ "0xefe82d7b1e7bed2e3bfe7b5a155cff7a5adf0dcc",
+ "0x93d1f6303711e5c9fa849cfad38d5782740d39fe"]
+iex(2)> ExW3.balance(Enum.at(accounts, 0))                                      
+100000000000000000000
+iex(3)> ExW3.block_number()            
+0
+iex(4)> simple_storage_abi = ExW3.load_abi("test/examples/build/SimpleStorage.abi")
+%{
+  "get" => %{
+    "constant" => true,
+    "inputs" => [],
+    "name" => "get",
+    "outputs" => [%{"name" => "", "type" => "uint256"}],
+    "payable" => false,
+    "stateMutability" => "view",
+    "type" => "function"
+  },
+  "set" => %{
+    "constant" => false,
+    "inputs" => [%{"name" => "_data", "type" => "uint256"}],
+    "name" => "set",
+    "outputs" => [],
+    "payable" => false,
+    "stateMutability" => "nonpayable",
+    "type" => "function"
+  }
+}
+iex(5)> contract_address = ExW3.Contract.deploy("test/examples/build/SimpleStorage.bin", %{from: Enum.at(accounts, 0), gas: 150000})
+"0xecac9f4000ae355c7d33481edb0fddbece502423"
+iex(6)> storage_pid = ExW3.Contract.at(simple_storage_abi, contract_address) 
+#PID<0.257.0>
+iex(7)> ExW3.Contract.method(storage_pid, "get")
+{:ok, 0}
+iex(8)> ExW3.Contract.method(storage_pid, "set", [1], %{from: Enum.at(accounts, 0)})
+{:ok, "0xb8a6ee58c88efcea775452a68fac20e47bda6ca933aa25dd85c4a97b0cfbf43f"}
+iex(9)> ExW3.Contract.method(storage_pid, "get")                          
+{:ok, 1}
+```
+
+For bonus style points you can use snake case keywords for the method names. For example:
+
+```elixir
+ExW3.Contract.method(pid, "fooBar")
+```
+
+is the same as:
+
+```elixir
+ExW3.Contract.method(pid, :foo_bar)
+```
+
+
+## Compiling solidity
 
 Ensure you have solc installed: