nats
Version:
Node.js client for NATS, a lightweight, high-performance cloud native messaging system
166 lines • 6.73 kB
JavaScript
"use strict";
var __await = (this && this.__await) || function (v) { return this instanceof __await ? (this.v = v, this) : new __await(v); }
var __asyncGenerator = (this && this.__asyncGenerator) || function (thisArg, _arguments, generator) {
if (!Symbol.asyncIterator) throw new TypeError("Symbol.asyncIterator is not defined.");
var g = generator.apply(thisArg, _arguments || []), i, q = [];
return i = {}, verb("next"), verb("throw"), verb("return", awaitReturn), i[Symbol.asyncIterator] = function () { return this; }, i;
function awaitReturn(f) { return function (v) { return Promise.resolve(v).then(f, reject); }; }
function verb(n, f) { if (g[n]) { i[n] = function (v) { return new Promise(function (a, b) { q.push([n, v, a, b]) > 1 || resume(n, v); }); }; if (f) i[n] = f(i[n]); } }
function resume(n, v) { try { step(g[n](v)); } catch (e) { settle(q[0][3], e); } }
function step(r) { r.value instanceof __await ? Promise.resolve(r.value.v).then(fulfill, reject) : settle(q[0][2], r); }
function fulfill(value) { resume("next", value); }
function reject(value) { resume("throw", value); }
function settle(f, v) { if (f(v), q.shift(), q.length) resume(q[0][0], q[0][1]); }
};
Object.defineProperty(exports, "__esModule", { value: true });
exports.QueuedIteratorImpl = void 0;
/*
* Copyright 2020-2022 The NATS Authors
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
const util_1 = require("./util");
const core_1 = require("./core");
class QueuedIteratorImpl {
constructor() {
this.inflight = 0;
this.filtered = 0;
this.pendingFiltered = 0;
this.processed = 0;
this.received = 0;
this.noIterator = false;
this.done = false;
this.signal = (0, util_1.deferred)();
this.yields = [];
this.iterClosed = (0, util_1.deferred)();
this.time = 0;
this.yielding = false;
}
[Symbol.asyncIterator]() {
return this.iterate();
}
push(v) {
if (this.done) {
return;
}
if (typeof v === "function") {
this.yields.push(v);
this.signal.resolve();
return;
}
const { ingest, protocol } = this.ingestionFilterFn
? this.ingestionFilterFn(v, this.ctx || this)
: { ingest: true, protocol: false };
if (ingest) {
if (protocol) {
this.filtered++;
this.pendingFiltered++;
}
this.yields.push(v);
this.signal.resolve();
}
}
iterate() {
return __asyncGenerator(this, arguments, function* iterate_1() {
if (this.noIterator) {
throw new core_1.NatsError("unsupported iterator", core_1.ErrorCode.ApiError);
}
if (this.yielding) {
throw new core_1.NatsError("already yielding", core_1.ErrorCode.ApiError);
}
this.yielding = true;
try {
while (true) {
if (this.yields.length === 0) {
yield __await(this.signal);
}
if (this.err) {
throw this.err;
}
const yields = this.yields;
this.inflight = yields.length;
this.yields = [];
for (let i = 0; i < yields.length; i++) {
if (typeof yields[i] === "function") {
const fn = yields[i];
try {
fn();
}
catch (err) {
// failed on the invocation - fail the iterator
// so they know to fix the callback
throw err;
}
// fn could have also set an error
if (this.err) {
throw this.err;
}
continue;
}
// only pass messages that pass the filter
const ok = this.protocolFilterFn
? this.protocolFilterFn(yields[i])
: true;
if (ok) {
this.processed++;
const start = Date.now();
yield yield __await(yields[i]);
this.time = Date.now() - start;
if (this.dispatchedFn && yields[i]) {
this.dispatchedFn(yields[i]);
}
}
else {
this.pendingFiltered--;
}
this.inflight--;
}
// yielding could have paused and microtask
// could have added messages. Prevent allocations
// if possible
if (this.done) {
break;
}
else if (this.yields.length === 0) {
yields.length = 0;
this.yields = yields;
this.signal = (0, util_1.deferred)();
}
}
}
finally {
// the iterator used break/return
this.stop();
}
});
}
stop(err) {
if (this.done) {
return;
}
this.err = err;
this.done = true;
this.signal.resolve();
this.iterClosed.resolve(err);
}
getProcessed() {
return this.noIterator ? this.received : this.processed;
}
getPending() {
return this.yields.length + this.inflight - this.pendingFiltered;
}
getReceived() {
return this.received - this.filtered;
}
}
exports.QueuedIteratorImpl = QueuedIteratorImpl;
//# sourceMappingURL=queued_iterator.js.map