This is a Rust implementation of a Music Licensing System Smart Contract for the Internet Computer Web3 platform. It is designed to manage songs, owners, and licenses in the context of a music licensing platform. The system provides functionalities such as creating, updating, and deleting songs, managing song ownership, and handling license requests.

• Rust
• Internet Computer SDK
• IC CDK

1. Clone the repository:

   git clone https://github.com/loboo34/music-licensing-ICP.git
   cd music-licensing-ICP
   npm install
   dfx start --background --clean
   npm run gen-deploy

• SongStorage: Alias for StableBTreeMap<u64, Song> to store songs.
• OwnerStorage: Alias for StableBTreeMap<u64, Owner> to store owners.
• LicenseStorage: Alias for StableBTreeMap<u64, License> to store licenses.
• LicenseeStorage: Alias for StableBTreeMap<u64, Licensee> to store licensees.

• Song, Owner, License, Licensee: Structs representing Song, Owner, License, and Licensee entities.
  • Implement CandidType, Clone, Serialize, Deserialize, and provide default values.

• Storable and BoundedStorable implemented for Song, Owner, License, and Licensee.
  • Storable: Conversion to and from bytes.
  • BoundedStorable: Defines maximum size and whether the size is fixed.

• MEMORY_MANAGER: Manages virtual memory.
• ID_COUNTER: Keeps track of global IDs.
• SONG_STORAGE, OWNER_STORAGE, LICENSE_STORAGE, LICENSEE_STORAGE: Stable BTreeMaps for storing songs, owners, licenses, and licensees.

• SongPayload, OwnerPayload, UpdateSongPayload, LicensePayload, ApprovePayload, LicenseePayload: Payload data structures for various operations.

• Functions annotated with ic_cdk::query are read-only queries.
• Functions annotated with ic_cdk::update are updates, which can modify the state.

Memory is allocated using a MemoryManager from the ic-stable-structures crate:

static MEMORY_MANAGER: RefCell<MemoryManager<DefaultMemoryImpl>> = // initialized

This manages allocating VirtualMemory for storages.

Unique IDs are generated using a thread-local IdCell:

static ID_COUNTER: RefCell<IdCell> = // initialized

The counter is incremented when adding new records.

Records are stored in thread-local StableBTreeMaps:

static SONG_STORAGE: RefCell<SongStorage> = // initialized
static OWNER_STORAGE: RefCell<OwnerStorage> = // initialized
static LICENSE_STORAGE: RefCell<LicenseStorage> = // initialized
static LICENSEE_STORAGE: RefCell<LicenseeStorage> = // initialized

Each storage maps IDs to their respective entities (songs, owners, licenses, and licensees).

• get_song(id: u64): Retrieve a song by ID.
• get_all_songs(): Retrieve all licensable songs.
• create_song(payload: SongPayload): Create a new song.
• update_song(payload: UpdateSongPayload): Update an existing song.
• delete_song(auth_key: String, id: u64): Delete a song.

• get_song_owner(id: u64): Retrieve the owner of a song.
• create_owner(payload: OwnerPayload): Create a new owner.

• get_license(id: u64): Retrieve a license by ID.
• get_owner_license_requests(id: u64): Retrieve licenses requested by an owner.
• get_licensee_licenses(id: u64): Retrieve licenses associated with a licensee.
• create_license_request(payload: LicensePayload): Create a license request.
• approve_license(payload: ApprovePayload): Approve a license.

• NotFound: Indicates that an entity (song, owner, license) could not be found.
• InvalidPayload: Indicates an issue with the payload during creation or update.
• AlreadyApproved: Indicates an attempt to approve a license that has already been approved.
• Unauthorized: Indicates that the user does not have the necessary permissions.

To learn more before you start working with music_licensing, see the following documentation available online:

• Quick Start
• SDK Developer Tools
• Rust Canister Devlopment Guide
• ic-cdk
• ic-cdk-macros
• Candid Introduction
• JavaScript API Reference

If you want to start working on your project right away, you might want to try the following commands:

cd music-licensing-ICP/
dfx help
dfx canister --help

If you want to test your project locally, you can use the following commands:

# Starts the replica, running in the background
dfx start --background

# Deploys your canisters to the replica and generates your candid interface
dfx deploy

Once the job completes, your application will be available at http://localhost:4943?canisterId={asset_canister_id}.

If you have made changes to your backend canister, you can generate a new candid interface with

npm run generate

at any time. This is recommended before starting the frontend development server, and will be run automatically any time you run dfx deploy.

If you are making frontend changes, you can start a development server with

npm start

Which will start a server at http://localhost:8080, proxying API requests to the replica at port 4943.

If you are hosting frontend code somewhere without using DFX, you may need to make one of the following adjustments to ensure your project does not fetch the root key in production:

• setDFX_NETWORK to production if you are using Webpack
• use your own preferred method to replace process.env.DFX_NETWORK in the autogenerated declarations
  • Setting canisters -> {asset_canister_id} -> declarations -> env_override to a string in dfx.json will replace process.env.DFX_NETWORK with the string in the autogenerated declarations
• Write your own createActor constructor