multipartkit/limit

Types

LimitConfigError

Why a Limits value could not be constructed.

Returned by new when a field receives a non-positive value. field names the offending field so a single handler can produce a meaningful error message even when several limits are misconfigured at once (the first failing field stops further checks).

pub type LimitConfigError {
  NonPositiveLimit(field: String, given: Int)
}

Constructors

NonPositiveLimit(field: String, given: Int)

Limits

opaque </>

Limits applied during parsing to bound resource consumption.

All limits are inclusive: a value equal to the limit is allowed; the (limit + 1)-th byte / part triggers the error.

Limits is an opaque type. Construct via new (validated, recommended) or default_limits (conservative presets), and inspect values through the max_body_bytes / max_part_bytes / max_parts / max_header_bytes accessor functions — direct field access was available in pre-1.0 releases but has been removed so the representation can evolve without breaking external callers.

pub opaque type Limits

Values

default_limits

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pub fn default_limits() -> Limits

Conservative defaults used by parse and parse_stream when no explicit limits are supplied.

max_body_bytes

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pub fn max_body_bytes(limits: Limits) -> Int

Total-input byte budget. See Limits.max_body_bytes.

max_header_bytes

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pub fn max_header_bytes(limits: Limits) -> Int

Per-part header-block byte budget. See Limits.max_header_bytes.

max_part_bytes

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pub fn max_part_bytes(limits: Limits) -> Int

Per-part body byte budget. See Limits.max_part_bytes.

max_parts

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pub fn max_parts(limits: Limits) -> Int

Maximum number of parts. See Limits.max_parts.

new

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pub fn new(
  max_body_bytes max_body_bytes: Int,
  max_part_bytes max_part_bytes: Int,
  max_parts max_parts: Int,
  max_header_bytes max_header_bytes: Int,
) -> Result(Limits, LimitConfigError)

Construct a Limits value with validation. Each field must be >= 1; otherwise the returned Error names the first failing field.

Use this in any path where the limit values come from configuration, CLI flags, request input, or other dynamic input. For trusted constants the direct Limits(...) constructor is also fine, but callers that want a stable surface ahead of the Limits type being closed (see the upcoming opaque-type work) should prefer new.

Example: import multipartkit/limit

case limit.new( max_body_bytes: 5_000_000, max_part_bytes: 2_000_000, max_parts: 50, max_header_bytes: 8_192, ) { Ok(limits) -> … Error(limit.NonPositiveLimit(field: f, given: g)) -> … }