Struct BlockAssembler 

pub struct BlockAssembler { /* private fields */ }

Reassembles Block1 fragments into a complete request payload.

RFC 7959 §2.5: The server collects Block1 fragments from the client, validating sequential block numbers and consistent SZX values. Once the final block (M=0) arrives, the full payload is returned.

Implementations

impl BlockAssembler

pub fn new(max_payload: usize) -> Self

Creates a new assembler with default block size and the given payload limit.

Arguments

• max_payload - Maximum total payload size after reassembly. Prevents resource exhaustion from unbounded block sequences.

pub fn process_block( &mut self, block: &BlockOption, data: &[u8], ) -> CoapResult<bool>

Processes an incoming Block1 fragment.

Validates that blocks arrive in order and that the reassembled payload does not exceed the configured maximum size.

Returns true when the final block has been received and the full payload is available via payload().

pub fn payload(&self) -> Option<&[u8]>

Returns the reassembled payload, or None if transfer is incomplete.

pub fn into_payload(self) -> CoapResult<Vec<u8>>

Consumes the assembler and returns the reassembled payload.

Returns Err if the transfer is not yet complete.

pub fn szx(&self) -> u8

Returns the negotiated block size exponent.

pub fn is_complete(&self) -> bool

Returns whether the final block has been received.

pub fn reset(&mut self)

Resets the assembler for reuse.

Trait Implementations

impl Debug for BlockAssembler

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.