Struct ClientConfig 

pub struct ClientConfig {
    pub concurrency: usize,
    pub upload_window: usize,
    pub download_window: usize,
    pub compress: bool,
    pub chunk_size: u64,
    pub max_retries: u32,
    pub base_retry_delay_ms: u32,
    pub max_retry_delay_ms: u32,
    pub timeout_ms: u32,
    pub auto_tune: bool,
    pub tune_ttl_ms: u64,
    pub compress_level: CompressLevel,
}

Runtime configuration of the WASM engine.

Fields

concurrency: usize

Global cap on concurrent in-flight HTTP transfers (default 4).

Every upload chunk POST and download range GET acquires a permit from a shared pool, so this bounds the engine’s TOTAL network parallelism — across all files AND all per-file windows combined (a single file can still open up to upload_window / download_window requests, but never more than concurrency in total).

upload_window: usize

In-flight chunk window for a single file’s upload (default 8).

Independent of concurrency: one file keeps up to upload_window chunks in flight, so a high-latency link stays saturated (throughput is bounded by bandwidth, not chunk_size / RTT).

download_window: usize

In-flight byte-range window for a single file’s download (default 4).

A large file is downloaded as download_window concurrent Range GETs so its throughput is bounded by bandwidth instead of one connection’s chunk_size / RTT (tus-style parallel transfer). Set to 1 to fall back to the sequential single-connection path.

compress: bool

Request zrip compression from the server / compress uploads.

chunk_size: u64

Fixed chunk size used to slice files and byte-range downloads (default 2 MiB).

The same value is used for both upload chunking and parallel download range splits, so a single config option represents the budget for both paths (larger = fewer, bigger transfers; bounded by the server’s upload limit, memory, and the per-file window budget).

max_retries: u32

Maximum retries per chunk/file (default 3).

base_retry_delay_ms: u32

Initial backoff delay in ms (default 500).

max_retry_delay_ms: u32

Backoff ceiling in ms (default 30s).

timeout_ms: u32

Per-request timeout in ms (default 60s).

auto_tune: bool

Adaptive tuning (TCP-style ramp over real transfers), off by default.

Opting in is what makes the engine measure the link: without it the knobs below are used exactly as configured.

In the browser a settled result is persisted in localStorage (per origin + direction) for up to tune_ttl_ms, so a page refresh does not re-ramp; the native client keeps it in memory only.

tune_ttl_ms: u64

How long a cached tuning result stays usable (milliseconds, default 1 hour). 0 disables the cache entirely — every transfer re-ramps.

compress_level: CompressLevel

Client-side compression level policy, defaulting to CompressLevel::Balanced.

Absent config resolves to whatever the server advertises as its own default level, so a client that never sets the field negotiates the server’s choice. compress: false still forces identity regardless of this field.

Implementations

impl ClientConfig

pub fn request_budget(&self) -> usize

Concurrent HTTP requests the client may keep in flight: concurrency files × the widest per-file window.

The pool is a bound, not the parallelism knob: sized to concurrency alone it would clamp every file to one request and make the per-file window ineffective (see tune::request_budget).

impl ClientConfig

pub fn from_js(opts: &JsValue) -> ClientConfig

Parse configuration from a JS object literal, e.g. { concurrency: 4, compress: true, chunkSize: 2097152 }.

Safe to call with null/undefined (returns defaults) — this also keeps native (non-wasm) unit tests runnable.

pub fn backoff_ms(&self, attempt: u32) -> u32

Exponential backoff delay for a failed attempt (0-based).

2^attempt * base, clamped to max. Bounded so a hung peer cannot grow the delay without limit.

Trait Implementations

impl Clone for ClientConfig

fn clone(&self) -> Self

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for ClientConfig

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

Formats the value using the given formatter.

impl Default for ClientConfig

fn default() -> Self

Returns the “default value” for a type.