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Streaming Payments ​

The maintained streaming-payment implementation is the standalone con_stream_payments package in xian-contracts, not the canonical currency contract.

What The Package Does ​

con_stream_payments creates time-based escrowed streams against an external token contract.

Each stream:

  • escrows the full budget up front
  • lets value accrue over time
  • lets the sender or receiver claim the accrued portion
  • lets the sender shorten the stream and recover the unvested refund
  • lets the receiver forfeit the unvested part of the stream
  • supports permit-style creation flows
  • exposes claimable_amount(...) and stream_info(...) read helpers for clients

Token Dependency ​

The streamed token contract must expose:

  • transfer(amount, to)
  • transfer_from(amount, to, main_account)

con_stream_payments validates that interface before using the token.

Core Flow ​

  1. deploy con_stream_payments
  2. approve the stream-payments contract on the token contract when escrow funding requires transfer_from
  3. create the stream with start time, close time, receiver, and rate
  4. call balance_stream(...) as time passes
  5. finalize, shorten, or forfeit the stream as needed

Encode begins, closes, permit deadlines, and close-time updates as YYYY-MM-DD HH:MM:SS.

Important Behavior ​

  • accrual is lazy; nothing runs between blocks
  • the contract uses block time (now) when computing accrued value
  • event names are:
    • StreamCreated
    • StreamBalanced
    • StreamCloseChanged
    • StreamForfeited
    • StreamFinalized
  • duplicate schedules from the same sender are separated by a sender nonce in the stream id

Caveats ​

  • change_close_time(...) supports shortening or immediate close, not arbitrary extension in place
  • create_stream_from_permit(...) authorizes the stream parameters, but the token-side approval needed for escrow funding has to exist