Implement Streaming Rate Calculator

[Shredder401k]

Difficulty: Medium
Type: Utility Function

Summary

Implement utility functions to calculate streaming rates (tokens per second/day) for streams.

Current Behaviour

No rate calculation utilities.

Expected Behaviour

Users can query streaming rate for any stream in various time units.

Suggested Implementation

pub fn get_stream_rate_per_second(env: Env, stream_id: u64) -> Result<i128, Error>

pub fn get_stream_rate_per_day(env: Env, stream_id: u64) -> Result<i128, Error>

pub fn get_stream_rate_per_month(env: Env, stream_id: u64) -> Result<i128, Error>

Files or Areas Likely Affected

• contracts/Contract-V1/src/lib.rs (rate calculator functions)
• contracts/Contract-V1/src/math.rs (rate calculations)
• contracts/Contract-V1/src/test.rs

Acceptance Criteria

• get_stream_rate_per_second function implemented
• get_stream_rate_per_day function implemented
• get_stream_rate_per_month function implemented
• Functions calculate rate = total_amount / (end_time - start_time)
• Functions return accurate rates for all time units
• Functions handle paused_duration in calculation
• Day = 86400 seconds, Month = 2592000 seconds (30 days)
• Returns Error::StreamNotFound for invalid ID
• At least 8 tests: rate calculations for various durations, different time units, with paused duration, precision verification, very long streams, very short streams, rate consistency across units, stream not found
• Rustdoc explains rate calculations
• Code compiles without warnings

Additional Notes

Rates help users understand cash flow. Use consistent time unit definitions. Account for paused_duration in rate calculations.

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[heymide]

I'd like to be assigned to this issue. I'll deliver a clean, maintainable solution that matches the requirements.

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[Peolite001]

📋 Grainlify Application

@Peolite001 has applied to work on this issue as part of the Grainlify program.

I would love to work on this issue

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Repo Maintainers: To accept this application, review their application or assign @Peolite001 to this issue.

[KarenZita01]

Implementing a streaming rate calculator will provide accurate real-time monitoring of data flow, enabling better performance management and early detection of bottlenecks. With experience in real-time data processing and system optimization, I will develop a lightweight calculator that continuously measures throughput, processes rate changes efficiently, and integrates seamlessly with the existing streaming architecture.

[grantfox-oss]

🦊 GrantFox — @KarenZita01 has been assigned to this issue as part of the Third Campaign campaign!

Next steps:

1. Open a Pull Request referencing this issue (e.g., Closes #1477)
2. Your PR will be reviewed by the StellarStream-HQ maintainers

Good luck! Track your progress on GrantFox.