Starbase Platform Smart Contracts

Table of Contents

• Table of Contents
• Overview
• Implementation Details
• Deployment
• Gas Consumptions
• Development

Overview

The Starbase platform's smart contracts allow investors who hold STARs to participate in the crowdfunding events happening at the Starbase's web application. The smart contract receives STARs and/or ETH and exchanges it for the token offered during the platform's sale event. There is also a whitelist smart contract where investors are able to be whitelisted prior and/or during the crowdsale. A staking mechanism is in the works and should allow users to stake STARs for getting bonus tokens offered during a sale. The FundsSplitter contract enables fair distribution of received funds between the client and Starbase.

Implementation Details

• CompanyToken.sol

This contract creates a token with customized name, symbol and decimals. Upon its creation, the token transfer functionality is paused, that is to say no one is able to trade them. This is possible to be reverted only by the token contract owner - who is the Ethereum address that deployed the token mold contract. For this contract to work with TokenSale.sol, its ownership needs to be passed on to TokenSale contract instance that will manage the token sale.

Note: TokenSale does not need to have this smart contract to operate. It accepts any ERC20 smart contract with 18 decimals. For minting new tokens: TokenSale must have token contract ownership and token contract must be paused. For transferring existing tokens: Token contract must not be paused.

• Whitelist.sol

It allows the addition and/or removal of addresses to the whitelist registry. Both addition and removal of addresses is done via passing an array of Ethereum addresses to addManyToWhitelist and removeManyFromWhitelist functions within the contract. Only the contract owner has the ability to trigger such actions.

• FundsSplitter.sol

Contract that splits TokenSale funds between Starbase and client. Once deployed, it can serve as wallet parameter from the TokenSale contract by adding its address in as the wallet parameter in the TokenSale init function.

• TokenSale.sol

This contract is where the fundraising occurs.

This tokenSale allows for the minting of tokens on the fly or the distribution of tokens that are already minted:

When it mints, the ownership from the deployed CompanyToken contract needs to be passed on to TokenSale contract. This is accomplished via the transferOwnership function found in the zeppelin-solidity's Ownable.sol contract.

When it distributes already created tokens, these tokens must be sent to the TokenSale contract and the token contract must not be paused.

A TokenSale is successful once the sales reach the softCap. A TokenSale will not distribute token more than what was defined as the crowdsaleCap. Tokens are distributed on the go whether it is minted by the TokenSale or not. As long as the project has not reached the softCap, tokens are not yet distributed by the TokenSale contract.

Participation:

In order for investors to participate in the crowdsale using STARs, they need firstly to approve the transfer of STARs from them to the TokenSale contract. For this, the investor must call the approve function from the STAR token contract thus passing the number of STAR tokens it approves to TokenSale so it manages STARs for them during the token purchase event.

Afterwards, the investor must trigger buyTokens within TokenSale, so the token purchase event goes through. The investor then receives purchased tokens right away (if soft cap is reached).

In case TokenSale mints and distributes token, the investor will not be able to trade these tokens because token transfers are paused. Tokens need to be unpaused for the transfers to happen and this must be done most likely after the crowdsale is completed by the token owner. Token ownership after the crowdsale must be moved from the TokenSale contract to another Ethereum address, most likely the address of the project owner that is using the Starbase platform for its crowdfunding needs.

When the TokenSale distributes an ERC20 token, investors receive their tokens immediately.

TokenSale also accepts payments in ETH. This occurs when the isWeiAccepted is set on TokenSale deployment or during an ongoing sale by calling the setIsWeiAccepted function. This needs to be called by the TokenSale owner.

When isWeiAccepted is triggered and investor sends ether in the transaction by calling buyTokens, the function will automatically call the contract internal function buyTokensWithWei which handles the purchase with wei/ether.

Purchase process:

Technically, the purchase flow happens as follows using STAR: 1- a user that possesses STAR token must approve the crowdsale contract to transfer STAR tokens on its behalf. This happens on the Starbase client app which connects to Metamask.

2- client app calls the buyTokens function passing user address as beneficiary, contract checks whether user has given it allowance to spend STAR tokens on user's behalf.

3- if positive allowance, then crowdsale calculates the number of tokens to create and transfers these to user. Once token transfer is completed, it passes on STAR token from user to the Multisig wallet contract.

Purchase flow using ETH is straighforward. 1- weiIsAccepted must be set.

2- whitelisted user sends ETH to TokenSale

3- user receives tokens.

Deployment

Manual: Deployment with Remix is different, you need to have MetaMask installed and have the entire contract code at hand. To get the entire contract code use a tool such as truffle-flattener to concatenate all smart contract code files into one. Or simply look in the flats folder in this repo which is updated regularly. Then go to Remix paste the entire code there and deploy the contracts according to Remix's UI.

Automatic: Automatic deployments work via the non-public repo https://github.com/StarbaseCo/starbase-platform/tree/dev/tools using the yarn ts:deploy command

Whitelist

To deploy the Whitelist smart contract it is fairly straightforward. It has no parameters.

Company Token

Three parameters are necessary to pass upon contract deployment: string _name, string _symbol, uint8 _decimals. Note: new token standard in Ethereum are moving to have decimals as always 18. Something to bear in mind and tell Starbase clients in case they want a different figure for the parameters decimals in their token.

Token Sale

It is the more complex of the crowdsale contracts. To set the parameters of the crowdsale one needs to call the init function after the contract is deployed.

It has a number of mandatory parameters:

_startTime = 1496204377  // time in unix timestamp
_endTime  = 1590898777  // time in unix timestamp
_whitelist = "0xc99e045afdeb86ba44c153cf4498a3fada0bc6d6" // contract of a deployed whitelist contract
_starToken = "0xd70A7A39EFB10cfE34FD79Ea8c06BdB1974C8828" // Starbase STAR token contract
_companyToken =  "0xaee875686Ec9C7A29B29f4Cd48a55bdF816eb00c"  // the EC20 token deployed by the company and who has mint capability
_tokenOwnerAfterSale "0xrbb875686Ec9C7A29B29f4Cd48a55bdF816eb00c" // Address that the TokenSale will pass the token ownership to after it's finished. Only works when TokenSale mints tokens, otherwise must be `0x0`.
_rate = 100 // rate in ETH/company tokens. Here is if investor sends 1 ETH she receives 100 company tokens in return
_starRatePer1000 = 2 // rate STAR/company tokens. Here is upon sending of 1 STAR, investor receives 2 company tokens in return
_wallet = "0xB01B468423Da913afD743c13f17B01c2cF26b3e8" // address where funds collected in the TokenSale will go to. Generally, it will be a FundsSplitter contract if not otherwise specifically instructed incl. a slightly different TokenSale implementation.
_softCap = 200 // soft cap of the token sale. It tells the frontend application that a sale has been successful
_crowdsaleCap = 1000  // cap for the number of tokens to be minted. Here it is only 1000 tokens that will be sold in the token sale
_isWeiAccepted = true // Bool for acceptance of ether in token sale
_isMinting = false // Bool that indicates whether token sale mints new ERC20 tokens on sale or simply transfers existing ones

Gas consumption

• approve 45545

• BuyTokens 34238

Development

Dependencies

• node@10.11.x

Setting Up

• Clone this repository.

• Install all system dependencies.

  • cd truffle && npm install

• Compile contract code

  • node_modules/.bin/truffle compile

Running Tests

• npm test

Generate Flattened Contracts

To generate flattened version of contracts in flats/, type:

• npm run flat

To generate flatten version of contracts and serve them to remix, type:

• install remixd with npm -g remixd

• npm run remix

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.