Javascript bindings for the solidity compiler
#Nodejs usage
To use the solidity compiler via nodejs you can install it via npm
npm install solc
And then use it like so:
var solc = require('solc');
var input = "contract x { function g() {} }";
var output = solc.compile(input, 1); // 1 activates the optimiser
for (var contractName in output.contracts) {
// code and ABI that are needed by web3
console.log(contractName + ': ' + output.contracts[contractName].bytecode);
console.log(contractName + '; ' + JSON.parse( output.contracts[contractName].interface));
}
Starting from version 0.1.6, multiple files are supported with automatic import resolution by the compiler as follows:
var solc = require('solc');
var input = {
'lib.sol': 'library L { function f() returns (uint) { return 7; } }',
'cont.sol': 'import "lib.sol"; contract x { function g() { L.f(); } }'
};
var output = solc.compile({sources: input}, 1);
for (var contractName in output.contracts)
console.log(contractName + ': ' + output.contracts[contractName].bytecode);
Note that all input files that are imported have to be supplied, the compiler will not load any additional files on its own.
Starting from version 0.2.1, a callback is supported to resolve missing imports as follows:
var solc = require('solc');
var input = {
'cont.sol': 'import "lib.sol"; contract x { function g() { L.f(); } }'
};
function findImports(path) {
if (path === 'lib.sol')
return { contents: 'library L { function f() returns (uint) { return 7; } }' }
else
return { error: 'File not found' }
}
var output = solc.compile({sources: input}, 1, findImports);
for (var contractName in output.contracts)
console.log(contractName + ': ' + output.contracts[contractName].bytecode);
###Using a legacy version
In order to allow compiling contracts using a specific version of solidity, the solc.useVersion method is available. This returns a new solc object using the version provided. Note: version strings must match the version substring of the files availble in /bin/soljson-*.js. See below for an example.
var solc = require('solc');
// by default the latest version is used
// ie: solc.useVersion('latest')
// getting a legacy version
var solcV011 = solc.useVersion( 'v0.1.1-2015-08-04-6ff4cd6' );
var output = solcV011.compile( "contract t { function g() {} }", 1 );