maximize-iterator/dist/cjs/createProcessor.js

Maximize the parallel calls of an iterator supporting asyncIterator interface

"use strict";
Object.defineProperty(exports, "__esModule", {
    value: true
});
Object.defineProperty(exports, "default", {
    enumerable: true,
    get: function() {
        return createProcessor;
    }
});
var _asynccompat = /*#__PURE__*/ _interop_require_default(require("async-compat"));
function _interop_require_default(obj) {
    return obj && obj.__esModule ? obj : {
        default: obj
    };
}
var isError = function(err) {
    return err && err.stack !== undefined && err.message !== undefined;
};
function processDone(err, options, callback) {
    // mark this iteration done
    options.err = options.err || err;
    options.done = true;
    // process done
    if (!options.done || options.counter > 0) return false;
    callback(options.err, options.done);
    return true;
}
function processResult(err, keep, options, callback) {
    options.counter--;
    // mark this iteration done
    if (err && _asynccompat.default.defaultValue(options.error(err), false) || !err && !_asynccompat.default.defaultValue(keep, true)) {
        options.err = options.err || err;
        options.done = true;
    }
    // process done
    if (!options.done || options.counter > 0) return false;
    callback(options.err, options.done);
    return true;
}
function createProcessor(next, options, callback) {
    var isProcessing = false;
    return function processor(doneOrError) {
        var error = doneOrError;
        if (doneOrError && processDone(isError(error) ? error : null, options, callback)) return;
        if (isProcessing) return;
        isProcessing = true;
        while(options.counter < options.concurrency){
            if (options.done || !options.canProcess()) break;
            if (options.total >= options.limit) {
                processDone(null, options, callback);
                return;
            }
            options.total++;
            options.counter++;
            next(function(err, result) {
                if (err || result.done) {
                    return !processResult(err, false, options, callback) && !isProcessing ? processor() : undefined;
                }
                _asynccompat.default.asyncFunction(options.each, options.callbacks, result.value, function(err, keep) {
                    return !processResult(err, keep, options, callback) && !isProcessing ? processor() : undefined;
                });
            });
        }
        isProcessing = false;
    };
}
/* CJS INTEROP */ if (exports.__esModule && exports.default) { try { Object.defineProperty(exports.default, '__esModule', { value: true }); for (var key in exports) { exports.default[key] = exports[key]; } } catch (_) {}; module.exports = exports.default; }