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    moon_ratelimit

    Deterministic rate-limiting and resilience primitives with verified decision laws

    rate-limiting
    token-bucket
    gcra
    resilience
    backoff
    Download zip
    Version
    0.2.0
    License
    Apache-2.0
    Repository
    Last updated
    3 hours ago
    Downloads
    11

    No dependencies

    #Moon RateLimit

    Deterministic rate-limiting and resilience primitives, implemented in MoonBit with verified decision laws.

    #Implemented

    Token buckets with continuous refill and exact retry-after; GCRA stated as a theoretical-arrival-time invariant and proven equivalent to the bucket bitwise on dyadic schedules; fixed windows (with their boundary burst demonstrated, not hidden) and exact sliding windows over (now - window, now]; jittered exponential backoff in the three AWS shapes over a seeded SplitMix64, reproducible bit for bit. Every decision is a pure function of (state, now, weight): time is injected, never read.

    #Build and run

    Use MoonBit and Node.js.

    moon build --target js
node _build/js/debug/build/cmd/main/main.js examples/token-bucket.json
node _build/js/debug/build/cmd/main/main.js - < examples/gcra.json

    Pass - to read a UTF-8 JSON request from stdin (16 MiB cap). Success prints one JSON object; refusals print {"error": ...} and exit 1; usage mistakes exit 2. examples/ holds one runnable request per capability with pinned answers.

    #Library use

    import {
      "123123213weqw/moon_ratelimit" @ratelimit,
      "moonbitlang/core/json",
    }

    fn example(request : Json) -> Json raise {
      @ratelimit.execute(request)
    }

    execute(Json) -> Json raise is the standard boundary; run(Value) is the typed form. See docs/usage.md for every field.

    #Tests

    sh scripts/verify.sh          # four backends, fixtures, oracle, stats
SKIP_NATIVE=1 sh scripts/verify.sh

    19 MoonBit test declarations across four backends with --deny-warn; 8 CLI fixture cases; 4 pinned examples; an independent Python oracle that re-derives every answer (57 checks: fixtures, random dyadic schedules, bit-exact jitter tables); machine-checked statistics in PROJECT_STATS.md. See the project proposal (Chinese) and boundaries.

    InputError

    source
    pub(all) suberror InputError {
      InputError(String)
    } derive(Eq, 
    Debug    )

    impl Show for InputError

    InputError::equal

    source
    fn InputError::equal(InputError, InputError) -> Bool

    InputError::not_equal

    source
    fn InputError::not_equal(x : InputError, y : InputError) -> Bool

    InputError::output

    source
    fn InputError::output(self : InputError, logger : &Logger) -> Unit

    InputError::to_repr

    source

    InputError::to_string

    source
    fn InputError::to_string(self : InputError) -> String

    Value

    source
    pub(all) enum Value {
      Null
      Bool(Bool)
      Number(Double)
      String(String)
      Array(Array[Value])
      Object(Map[String, Value])
    } derive(Eq, 
    Debug    )

    A JSON-shaped semantic value. Requests and reports travel as these; object key order is never significant, and numbers are finite doubles.

    Value::canonical

    source
    fn Value::canonical(self : Value) -> String

    Character-lexical key order, so a report hashed or compared across backends and languages always spells the same.

    Value::equal

    source
    fn Value::equal(Value, Value) -> Bool

    Value::not_equal

    source
    fn Value::not_equal(x : Value, y : Value) -> Bool

    Value::to_json

    source

    Value::to_repr

    source

    arr

    source
    fn arr(value : Value) -> Array[Value] raise InputError

    execute

    source

    The standard JSON boundary: one request object in, one report object out. Failures raise InputError with a plain message.

    field

    source
    fn field(value : Value, key : String) -> Value

    fields_only

    source
    fn fields_only(value : Value, allowed : Array[String]) -> Unit raise InputError

    from_json

    source
    fn from_json(value : 
    Json    ) -> Value

    get

    source
    fn get(value : Value, key : String) -> Value

    has

    source
    fn has(value : Value, key : String) -> Bool

    num

    source
    fn num(value : Value) -> Double raise InputError

    obj

    source
    fn obj(value : Value) -> Map[String, Value] raise InputError

    optional_num

    source
    fn optional_num(value : Value, fallback : Double) -> Double raise InputError

    optional_str

    source
    fn optional_str(value : Value, fallback : String) -> String raise InputError

    record

    source
    fn record(fields : Array[(String, Value)]) -> Value

    required

    source
    fn required(value : Value, key : String) -> Value raise InputError

    run

    source
    fn run(request : Value) -> Value raise InputError

    The typed boundary over the same requests.

    str

    source
    fn str(value : Value) -> String raise InputError

    strings

    source
    fn strings(items : Array[String]) -> Value

    Source Files

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