Crowdfunding in Solidity

Crowdfunding developed in Solidity. It allows users to invest in promising projects and helps project creators raise funds in a decentralized and transparent manner.

Recursos

• Project Investment: Users can invest a specific amount in a project they find promising. Each investment helps the project reach its funding goal.
• Project Creation: Users can create their own projects, set a funding goal, and provide details about the project.
• Transparency: All investments are recorded on the blockchain, providing complete transparency on how much funds a project has raised.
• Security: The smart contract is developed in Solidity, ensuring the security and robustness of the crowdfunding system.

Contracts

The provided code is a decentralized crowdfunding contract system implemented in Solidity, allowing users to create and manage fundraising campaigns on the Ethereum blockchain. The system consists of two contracts: CampaignFactory and Campaign.

Contract Breakdown

1. CampaignFactory Contract

• Purpose: The CampaignFactory contract is responsible for creating and managing instances of crowdfunding campaigns (Campaign contracts).
• Key Components:
  • deployedCampaigns: An array that stores the addresses of all deployed campaigns.
  • createCampaign(): This function allows users to create a new campaign by specifying a minimum contribution. The creator of the campaign becomes the manager. The newly created campaign's address is added to the deployedCampaigns array.
  • getDeployedCampaigns(): A public view function that returns all the deployed campaigns' addresses.

2. Campaign Contract

• Purpose: The Campaign contract defines how individual crowdfunding campaigns function, including contributions, creating requests to use funds, approving requests, and finalizing payments.
• Key Components:
  • Request Struct: Defines the structure for fund withdrawal requests made by the campaign manager. It includes:
  • description: Reason for the fund transfer.
  • value: The amount to be transferred to the recipient.
  • recipient: The address that will receive the funds.
  • complete: Boolean to check if the request has been completed.
  • approvalCount: The number of contributors who have approved the request.
  • approvals: A mapping of contributors who have approved the request.
• State Variables:
  • requests: An array of Request structs that stores all the requests made by the manager.
  • manager: The address of the campaign creator, who manages the campaign.
  • minimumContribution: The minimum amount of ETH required to become an approver.
  • approvers: A mapping of addresses that tracks which contributors are eligible to vote on fund requests.
  • approversCount: The number of contributors who have sent funds and are eligible to approve requests.
• Modifiers:
  • restricted: Restricts access to certain functions (e.g., creating requests and finalizing requests) to only the campaign manager.