Issue #4 — Booking Creation with Payment

[yusuftomilola]

The core feature of the contract is book_workspace — a member selects a workspace, picks a time slot, pays the computed fee, and the contract records the booking. This issue also adds the three booking query functions.

Task

Building on Issue #3, add:

1. pub fn book_workspace(env, member, booking_id, workspace_id, start_time, end_time) -> Result<(), Error>

   • Call member.require_auth().
   • Return Error::BookingAlreadyExists if DataKey::Booking(booking_id.clone()) already exists.
   • Validate time range: start_time >= end_time || end_time <= now → Error::InvalidTimeRange.
   • Load workspace, return Error::WorkspaceNotFound if absent.
   • Return Error::WorkspaceUnavailable if !workspace.is_available.
   • Call Self::is_slot_available(...) → return Error::BookingConflict if false.
   • Compute cost: hourly_rate × ⌈(end_time - start_time) / 3600⌉ using div_ceil(3600).
   • Transfer payment from member to contract using token::Client::new(&env, &payment_token).transfer(&member, env.current_contract_address(), &amount).
   • Build Booking struct and save to DataKey::Booking(booking_id.clone()) in persistent storage.
   • Append booking_id to DataKey::WorkspaceBookings(workspace_id.clone()) in persistent storage.
   • Append booking_id to DataKey::MemberBookings(member.clone()) in persistent storage.
   • Emit event: topic (symbol_short!("booked"), booking_id), data (member, workspace_id, start_time, end_time, amount).

2. pub fn get_booking(env: Env, booking_id: String) -> Result<Booking, Error>

   • Read DataKey::Booking(booking_id) from persistent storage, return Error::BookingNotFound if absent.

3. pub fn get_member_bookings(env: Env, member: Address) -> Vec<String>

   • Read DataKey::MemberBookings(member) from persistent storage, return empty Vec if absent.

4. pub fn get_workspace_bookings(env: Env, workspace_id: String) -> Vec<String>

   • Read DataKey::WorkspaceBookings(workspace_id) from persistent storage, return empty Vec if absent.

Files to modify

• contracts/workspace_booking/src/lib.rs

Acceptance criteria

• cargo check -p workspace_booking and cargo clippy -p workspace_booking -- -D warnings pass.
• A successful booking transfers tokens from the member to the contract.
• Cost rounds up to the nearest full hour (e.g., 90-minute booking = 2 hours of payment).
• Overlapping bookings are rejected with Error(Contract, #6) (BookingConflict).
• Booking an unavailable workspace returns Error(Contract, #5) (WorkspaceUnavailable).
• get_member_bookings and get_workspace_bookings return the correct IDs after booking.
• Duplicate booking_id returns Error(Contract, #8) (BookingAlreadyExists).

Technical notes

• Use duration_secs.div_ceil(3600) — do not use (duration_secs + 3599) / 3600 (triggers manual_div_ceil clippy lint).
• Token transfer: from takes &Address, to takes an owned Address (env.current_contract_address() — no &).

[soma-enyi]

Gm Gm Maintainer!!!!
I would like to work on this issue!!!!

[Bosun-Josh121]

Hello,

I am an active open-source contributor and I have a strong background in backend and smart contract engineering (specifically Stellar/Soroban) and I would like to tackle this issue.

This issue aligns perfectly with my skillset as I have previously built similar functionality and have reviewed the current codebase, so I am prepared to navigate the architecture without issues.

I can commit to delivering a clean, tested solution within 24 hours. I value clear communication and i'm happy to iterate on any feedback during the review process.

[anonfedora]

I'm Anonfedora, I'm a Fullstack Blockchain Engr. I'm proficient in Rust (soroban), Rust serverside with Axum and tokio, Nestjs, epxressjs have vast experience in contributing and building on the Stellar ecosystem with the Rust using soroban's SDK.
I'm also good at comprehensively testing features.
ETA: < 10 hours

[devJaja]

Can I solve this issue please

[ryzen-xp]

Hi maintainers 👋
I’m a blockchain developer with strong expertise in Stellar, Rust,TS and Stellar SDK integrations. I’ve worked on multiple Stellar-based smart contract and backend systems.

I understand the scope of this issue and can deliver a reliable, production-quality solution with proper tests and documentation.
Plz assign me !!

ETA: 14 hours

[lynaDev2]

can i work on this eta is 4 hours

[auracule007]

Hi maintainers, I'm Promise Adedokun. I'm a blockchain developer with solid experience working with Stellar, Rust, and Soroban smart contracts, including token transfers and booking system logic. I'd like to work on this booking creation issue. I can implement the book_workspace function with member authentication, time validation, workspace availability checks, slot conflict detection, cost calculation with proper rounding, token transfer, storage persistence across multiple indices, and comprehensive query functions for retrieving bookings by ID, member, or workspace. My ETA is 6-8 hours.

[Nabeelahh]

Hi maintainer I have thoroughly read the description to this issue and I can resolve this according to the description required ensuring it meet all the acceptance criteria kindly assign.

[Nabeelahh]

Hi maintainer I have thoroughly read the description to this issue and I can resolve this according to the description required ensuring it meet all the acceptance criteria kindly assign.

[edehvictor]

Hello, please can I work on this

ETA: 3hrs

[Emmanuelluxury]

I’d like to work on this issue because it sits at the intersection of system design, financial logic, and secure contract architecture — areas I actively specialize in and enjoy building within. The problem requires careful handling of state transitions, precision math, and security constraints, which makes it both technically meaningful and impactful to the overall reliability of the protocol.

[OlufunbiIK]

Hi maintainers,

I’d like to work on this issue.

I have experience working with Rust smart contracts and implementing stateful logic such as bookings, validations, and token transfers. I’m comfortable handling persistent storage, event emission, and ensuring that contract logic follows strict validation and error handling.

Implementation approach

I will implement the following functions in contracts/workspace_booking/src/lib.rs:

1. book_workspace

• Require authentication using member.require_auth()

• Check if booking_id already exists and return Error::BookingAlreadyExists

• Validate the booking time range (start_time, end_time, and current time)

• Load the workspace and verify:

  • Workspace exists
  • Workspace is available

• Check for overlapping bookings using Self::is_slot_available(...)

• Compute booking cost using:
  duration_secs.div_ceil(3600) * hourly_rate

• Transfer payment from the member to the contract using token::Client

• Persist the Booking struct in DataKey::Booking

• Append booking_id to:

  • DataKey::WorkspaceBookings(workspace_id)
  • DataKey::MemberBookings(member)

• Emit the booked event with the required topic and data fields

2. Query functions

• get_booking — return booking or Error::BookingNotFound
• get_member_bookings — return member booking IDs or an empty Vec
• get_workspace_bookings — return workspace booking IDs or an empty Vec

Validation

I will ensure:

• cargo check -p workspace_booking passes
• cargo clippy -p workspace_booking -- -D warnings passes
• Cost calculation uses div_ceil(3600) to satisfy clippy
• Overlapping bookings are rejected correctly
• Token transfers occur successfully on booking
• All booking index lists update correctly

Please feel free to assign this issue to me if it’s available. I’d be happy to contribute