@parity/light.js
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A high-level reactive JS library optimized for light clients
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JavaScript
;
// Copyright 2015-2019 Parity Technologies (UK) Ltd.
// This file is part of Parity.
//
// SPDX-License-Identifier: MIT
Object.defineProperty(exports, "__esModule", { value: true });
var rxjs_1 = require("rxjs");
var types_1 = require("@parity/api/lib/util/types");
// @ts-ignore Unfortunately no types for memoizee/weak.
var memoizeeWeak = require("memoizee/weak");
var api_1 = require("../../api");
var operators_1 = require("../../utils/operators");
// Unsubscribe to the frequency/dependsOn observable after 2s with no subscriber
exports.UNSUB_DELAY = 2000;
/**
* Add metadata to an RpcObservable, and transform it into a ReplaySubject(1).
* It's a currified function.
* Pure function version of {@link createRpc}.
*
* @ignore
* @param metadata - The metadata to add.
* @example
* createRpc(metadata)(options) returns a RpcObservable.
* createRpc(metadata)(options)(someArgs) returns an Observable.
*/
var createRpcWithApi = memoizeeWeak(function (api, metadata) {
var args = [];
for (var _i = 2; _i < arguments.length; _i++) {
args[_i - 2] = arguments[_i];
}
if (!metadata.dependsOn && !metadata.frequency) {
throw new Error("Rpc$ '" + metadata.name + "' needs either a 'dependsOn' or a 'frequency' field.");
}
// The source Observable can either be another RpcObservable (in the
// `dependsOn` field), or an Observable built by merging all the
// FrequencyObservables
var source$ = metadata.dependsOn
? metadata.dependsOn.apply(metadata, args.concat([{ provider: api.provider }])) : rxjs_1.merge.apply(void 0, metadata.frequency.map(function (f) {
return f({ provider: api.provider });
}));
// The pipes to add
var pipes = [];
if (metadata.pipes && types_1.isFunction(metadata.pipes)) {
pipes.push.apply(pipes, metadata.pipes(api));
}
pipes.push(operators_1.distinctReplayRefCountDelay(exports.UNSUB_DELAY));
return source$.pipe.apply(source$, pipes);
}, {
length: false,
normalizer: function (_, otherArgs) {
var _a = Array.from(otherArgs), metadata = _a[0], args = _a.slice(1);
// Custom memoization function. The first argument (_, which is `api`),
// is memoized by reference. For the rest of the arguments, we create an
// unique id based on serialization.
// https://github.com/medikoo/memoizee/issues/99#issuecomment-422155924
return "" + metadata.name + JSON.stringify(args);
}
});
/**
* Add metadata to an RpcObservable, and transform it into a ReplaySubject(1).
* It's a currified function.
*
* @ignore
* @param metadata - The metadata to add.
* @example
* createRpc(metadata)(options) returns a RpcObservable.
* createRpc(metadata)(options)(someArgs) returns an Observable.
*/
var createRpc = function (metadata) { return function (options) {
if (options === void 0) { options = {}; }
return function () {
var args = [];
for (var _i = 0; _i < arguments.length; _i++) {
args[_i] = arguments[_i];
}
// Evaluate api only once we subscribe
return rxjs_1.defer(function () {
var provider = options.provider;
var api = provider ? api_1.createApiFromProvider(provider) : api_1.getApi();
return createRpcWithApi.apply(void 0, [api, metadata].concat(args));
});
};
}; };
exports.default = createRpc;