ethereum-libraries-direct-crowdsale
v3.1.1
Published
Direct crowdsale library used by crowdsale contracts
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DirectCrowdsaleLib
A crowdsale library provided by Modular to use for direct token/eth crowdsale contract deployment.
- Library Address
- License and Warranty
- Installation and Usage
- Change Log
- Functions
- init(DirectCrowdsaleLib.DirectCrowdsaleStorage storage, address, uint256[], uint256, uint8, CrowdsaleToken)
- receivePurchase(DirectCrowdsaleLib.DirectCrowdsaleStorage storage, uint256)
- setTokens(DirectCrowdsaleLib.DirectCrowdsaleStorage storage)
- withdrawTokens(DirectCrowdsaleLib.DirectCrowdsaleStorage storage)
- withdrawLeftoverWei(DirectCrowdsaleLib.DirectCrowdsaleStorage storage)
- withdrawOwnerEth(DirectCrowdsaleLib.DirectCrowdsaleStorage storage)
- getSaleData(DirectCrowdsaleLib.DirectCrowdsaleStorage storage)
- getTokensSold(DirectCrowdsaleLib.DirectCrowdsaleStorage storage)
- crowdsaleActive(DirectCrowdsaleLib.DirectCrowdsaleStorage storage)
- crowdsaleEnded(DirectCrowdsaleLib.DirectCrowdsaleStorage storage)
Library Address
v3.0.0
Main Ethereum Network: 0x092bD122deF1aCC867a78d974Fab83C8af31aB91
Rinkeby Test Network: 0xb71775a8724ab70d7b7e2a77015e396690304305
License and Warranty
Be advised that while we strive to provide professional grade, tested code we cannot guarantee its fitness for your application. This is released under The MIT License (MIT) and as such we will not be held liable for lost funds, etc. Please use your best judgment and note the following:
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
Installation and Usage
How to install
npm install ethereum-libraries-direct-crowdsale
How to link
Amend the deployment .js file in your truffle migrations/
directory as follows:
var DirectCrowdsaleLib = artifacts.require("ethereum-libraries-direct-crowdsale/contracts/DirectCrowdsaleLib.sol");
var OtherLibs = artifacts.require("package-for-other-libs/contracts/OtherLibs.sol");
var YourCrowdsaleContract = artifacts.require("./YourCrowdsaleContract.sol");
...
module.exports = function(deployer) {
deployer.deploy(DirectCrowdsaleLib, {overwrite: false});
deployer.link(DirectCrowdsaleLib, YourCrowdsaleContract);
deployer.deploy(YourCrowdsaleContract, arg1, arg2,...);
};
Note: If you have not created a second deployment .js file in the migrations/
directory, this needs to be done first. You cannot use the 1_initial_migration.js file for your migrations.
Note: The .link()
function should be called before you .deploy(YourCrowdsaleContract)
. Also, be sure to include the {overwrite: false}
when writing the deployer i.e. .deploy(DirectCrowdsaleLib, {overwrite: false})
. This prevents deploying the library onto the main network at your cost and uses the library already on the blockchain. The function should still be called however because it allows you to use it in your development environment. See below
Testing
Test: npm run test
Test Coverage: Solidity coverage is not currently emitting events properly for Solidity v0.4.21
solc Installation
version 0.4.21
For direction and instructions on how the Solidity command line compiler works see the documentation.
With standard JSON input
The Standard JSON Input provides an easy interface to include libraries. Include the following as part of your JSON input file:
{
"language": "Solidity",
"sources":
{
"YourCrowdsaleContract.sol": {
...
...
},
"CrowdsaleLib.sol": {
"content": "[Contents of CrowdsaleLib.sol]"
},
"DirectCrowdsaleLib.sol": {
"content": "[Contents of DirectCrowdsaleLib.sol]"
}
},
"settings":
{
...
"libraries": {
"YourContract.sol": {
"DirectCrowdsaleLib": "0x092bD122deF1aCC867a78d974Fab83C8af31aB91"
}
}
}
}
solc without standard JSON input
When creating unlinked binary, the compiler currently leaves special substrings in the compiled bytecode in the form of 'LibraryName____' which leaves a 20 byte space for the library's address. In order to include both deployed libraries in your bytecode create a file with one library string per line as follows:
"DirectCrowdsaleLib:0x092bD122deF1aCC867a78d974Fab83C8af31aB91"
then add the following flag to your command:
--libraries filename
Finally, if you have an unlinked binary already stored with the 'LibraryName____' placeholder, you can run the compiler with the --link flag and also include the following flag:
--libraries filename
solc documentation
See the solc documentation for further information.
solc-js Installation
version 0.4.21
Solc-js provides javascript bindings for the Solidity compiler and can be found here. Please refer to their documentation for detailed use.
This version of Solc-js also uses the standard JSON input to compile a contract. The entry function is compileStandardWrapper()
and you can create a standard JSON object explained under the solc section and incorporate it as follows:
var solc = require('solc');
var fs = require('fs');
var file = fs.readFileSync('/path/to/YourCrowdsaleContract.sol','utf8');
var directCrowdsaleLib = fs.readFileSync('./path/to/DirectCrowdsaleLib.sol','utf8');
var input = {
"language": "Solidity",
"sources":
{
"YourCrowdsaleContract.sol": {
"content": file
},
"DirectyCrowdsaleLib.sol": {
"content": directCrowdsaleLib
},
"CrowdsaleLib.sol": {
"content": crowdsaleLib
}
},
"settings":
{
...
"libraries": {
"YourCrowdsaleContract.sol": {
"DirectCrowdsaleLib": "0x092bD122deF1aCC867a78d974Fab83C8af31aB91"
}
}
...
}
}
var output = JSON.parse(solc.compileStandardWrapper(JSON.stringify(input)));
//Where the output variable is a standard JSON output object.
Solc-js Installation via Linking
Solc-js also provides a linking method if you have compiled binary code already with the placeholder. To link this library the call would be:
bytecode = solc.linkBytecode(bytecode, { 'DirectCrowdsaleLib': '0x4A0a5236E4D1aE19fc00C167E1D33f37870f53b1' });
Solc-js documentation
See the Solc-js documentation for further information.
Basic Usage
The Direct Crowdsale library provides functionality needed to launch an ETH in/token out crowdsale. It is made up of two library contracts, a base library and a library specific to this type of crowdsale structure. Both should be included in your project. The crowdsale will have some of the following characteristics:
- Sets a raise cap in terms of dollars and cents.
- Can provide price points in terms of dollars and cents for stepping up or stepping down prices during the sale.
- Can set the interval between price changes.
- Sets an exchange rate for dollars/ETH up to three days before the sale begins.
- Can set a percentage of extra tokens to burn after the sale ends with the remainder going back to the owners.
The crowdsale contract should put the init
function in the constructor with the required parameters given. The crowdsale library functions will generally return false and log an error event when submitted parameters are either wrong or the call will not work.
DISCLAIMER: As always, please ensure you review this code thoroughly for your team's use. We strive to make our code as solid, clean, and well documented as possible but will not accept liability for unforeseen circumstances in which value is lost or stolen. This includes but not limited to any inability to meet signature requirements to move funds, loss of private keys, transactions you deem unauthorized from an owner's account, etc. The library code has been thoroughly tested by our team and believe it to be suitable enough to be posted in our open source repository, however, you are still responsible for its implementation and security in your smart contract. Please use your best judgment. Please let us know immediately if you have discovered any issues or vulnerabilities with this library.
Change Log
v3.0.0
- Merge CrowdsaleLib into single file
- Create own package
v2.2.1
- Removes exchange rates for just tokens/eth pricing
- Removes explicit cap since the sale is capped by the number of tokens being sold
v2.1.0
- Update compiler to 0.4.18 and explicitly define function scopes, minor fixes from audit.
v2.0.0
- This version changes the sale data structure for all crowdsales.
Functions
The following is the list of functions available to use in your smart contract.
init(DirectCrowdsaleLib.DirectCrowdsaleStorage storage, address, uint256[], uint256, uint8, CrowdsaleToken)
(DirectCrowdsaleLib.sol, line 95)
Constructor. Initialize the crowdsale with owner, sale data, endTime, burn percentage of leftover tokens, and the address of the deployed token contract. Passes some values to the base constructor then sets the direct crowdsale specific storage variables. The sale data consists of an array of 3-item "sets" such that, in each 3 element set, 1 is timestamp, 2 is price in cents at that time, 3 is address purchase cap at that time, this value should be set to 0 for a direct crowdsale.
Arguments
DirectCrowdsaleLib.DirectCrowdsaleStorage self
address[] _owner
Address of crowdsale owner
uint256[] _saleData
Array of 2 item sets such that, in each 2 element set, 1 is timestamp, and 2 is price in tokens/ETH at that time. The very first item should be the timestamp for the auction start.
uint256 _endTime Timestamp
of the end time.
uint8 _percentBurn
Percentage of extra tokens to burn after the sale.
CrowdsaleToken _token
Token being sold in the crowdsale.
Returns
No return
receivePurchase(DirectCrowdsaleLib.DirectCrowdsaleStorage storage, uint256)
(DirectCrowdsaleLib.sol, line 131)
Accepts payment for tokens and allocates tokens available to withdraw to the buyers place in the token mapping. Calls validPurchase to check if the purchase is legal. If the purchase goes over the raise cap for the sale, the ether is returned and no tokens are transferred. This also updates the token's price when the time milestone passes.
Tokens purchased are calculated by multiplying the wei contributed by the tokensPerEth value, then moving the decimal place to reflect the token's specified granularity. Mappings for buyer contribution, tokens purchased, and any leftover wei are updated, as well as total wei raised in the sale.
Arguments
DirectCrowdsaleLib.DirectCrowdsaleStorage self
The data storage in the calling contract.
uint256 _amount
Amount being paid in terms of wei.
Returns
bool True if transaction confirmed or revoked successfully.
setTokens(DirectCrowdsaleLib.DirectCrowdsaleStorage storage)
(DirectCrowdsaleLib.sol, line 197)
Used to the token balance after transferring tokens to the sale contract. This should be called after depositing the tokens and before the sale begins.
Arguments
DirectCrowdsaleLib.DirectCrowdsaleStorage self
Returns
bool
withdrawTokens(DirectCrowdsaleLib.DirectCrowdsaleStorage storage)
(DirectCrowdsaleLib.sol, line 228)
Allows a user to withdraw their purchased tokens whenever they want, provided they actually have purchased some. The token's transferFrom function is called so that the token contract transfers tokens from the owners address to the buyer's address. The owner can also call this function after the sale is over to withdraw the remaining tokens that were not sold and trigger the functionality to burn unwanted tokens.
Arguments
DirectCrowdsaleLib.DirectCrowdsaleStorage self
Returns
bool
withdrawLeftoverWei(DirectCrowdsaleLib.DirectCrowdsaleStorage storage)
(DirectCrowdsaleLib.sol, line 261)
If a user had sent wei that didn't add up exactly to a whole number of tokens, the leftover wei will be recorded in the leftoverWei mapping for that user. This function allows the user to withdraw the excess.
Arguments
DirectCrowdsaleLib.DirectCrowdsaleStorage self
Returns
bool
withdrawOwnerEth(DirectCrowdsaleLib.DirectCrowdsaleStorage storage)
(DirectCrowdsaleLib.sol, line 277)
Allows the owner of the crowdsale to withdraw all the contributed ether after the sale is over. ETH must have been contributed in the sale. It sets the owner's balance to 0 and transfers all the ETH.
Arguments
DirectCrowdsaleLib.DirectCrowdsaleStorage self
Returns
bool
getSaleData(DirectCrowdsaleLib.DirectCrowdsaleStorage storage)
(DirectCrowdsaleLib.sol, line 298)
Returns a 2 element array with index-0 being the timestamp, and index-1 being the current token price in ETH.
Arguments
EvenDistroCrowdsaleLib.EvenDistroCrowdsaleStorage self
Returns
uint256[2]
getTokensSold(DirectCrowdsaleLib.DirectCrowdsaleStorage storage)
(DirectCrowdsaleLib.sol, line 320)
Returns the total amount of tokens sold at the time of calling.
Arguments
EvenDistroCrowdsaleLib.EvenDistroCrowdsaleStorage self
Returns
uint256
crowdsaleActive(DirectCrowdsaleLib.DirectCrowdsaleStorage storage)
(DirectCrowdsaleLib.sol, line 327)
Returns true if the crowdsale is currently active. (If now is between the start and end time)
Arguments
DirectCrowdsaleLib.DirectCrowdsaleStorage self
Returns
bool
crowdsaleEnded(DirectCrowdsaleLib.DirectCrowdsaleStorage storage)
(DirectCrowdsaleLib.sol, line 334)
Returns true if the crowdsale is over. (now is after the end time)
Arguments
DirectCrowdsaleLib.DirectCrowdsaleStorage self
Returns
bool