ccxws/__tests__/BasicClient.spec.ts

Websocket client for 37 cryptocurrency exchanges

/* eslint-disable @typescript-eslint/require-await */

import { EventEmitter } from "events";
import { expect } from "chai";
import sinon from "sinon";
import { BasicClient } from "../src/BasicClient";

class TestClient extends BasicClient {
    protected _onMessage = sinon.stub();
    protected _sendSubTicker = sinon.stub();
    protected _sendSubCandles = sinon.stub();
    protected _sendUnsubCandles = sinon.stub();
    protected _sendUnsubTicker = sinon.stub();
    protected _sendSubTrades = sinon.stub();
    protected _sendUnsubTrades = sinon.stub();
    protected _sendSubLevel2Snapshots = sinon.stub();
    protected _sendUnsubLevel2Snapshots = sinon.stub();
    protected _sendSubLevel2Updates = sinon.stub();
    protected _sendUnsubLevel2Updates = sinon.stub();
    protected _sendSubLevel3Snapshots = sinon.stub();
    protected _sendUnsubLevel3Snapshots = sinon.stub();
    protected _sendSubLevel3Updates = sinon.stub();
    protected _sendUnsubLevel3Updates = sinon.stub();
}

function buildInstance() {
    const instance = new TestClient("wss://localhost/test", "test", mockSmartWss);
    instance.hasTickers = true;
    instance.hasTrades = true;
    instance.hasCandles = true;
    instance.hasLevel2Snapshots = true;
    instance.hasLevel2Updates = true;
    instance.hasLevel3Updates = true;

    sinon.stub((instance as any)._watcher, "start");
    sinon.stub((instance as any)._watcher, "stop");
    return instance;
}

function mockSmartWss() {
    const wss = new EventEmitter() as any;
    wss.connect = sinon.stub();
    wss.close = sinon.stub();
    wss.mockEmit = function (event, payload) {
        if (event === "connected") this.isConnected = true;
        this.emit(event, payload);
    };
    wss.isConnected = false;
    wss.close.callsFake(() => {
        wss.mockEmit("closing");
        setTimeout(() => wss.mockEmit("closed"), 0);
    });
    return wss;
}

describe("BasicClient", () => {
    let instance;

    before(() => {
        instance = buildInstance();
        instance._connect();
    });

    describe("on first subscribe", () => {
        it("should open a connection", () => {
            instance.subscribeTrades({ id: "BTCUSD" });
            expect(instance._wss).to.not.be.undefined;
            expect(instance._wss.connect.callCount).to.equal(1);
        });
        it("should send subscribe to the socket", () => {
            instance._wss.mockEmit("connected");
            expect(instance._sendSubTrades.callCount).to.equal(1);
            expect(instance._sendSubTrades.args[0][0]).to.equal("BTCUSD");
            expect(instance._sendSubTrades.args[0][1]).to.be.an("object");
        });
        it("should start the watcher", () => {
            expect(instance._watcher.start.callCount).to.equal(1);
        });
    });

    describe("on subsequent subscribes", () => {
        it("should not connect again", () => {
            instance.subscribeTrades({ id: "LTCBTC" });
            expect(instance._wss.connect.callCount).to.equal(1);
        });
        it("should send subscribe to the socket", () => {
            expect(instance._sendSubTrades.callCount).to.equal(2);
            expect(instance._sendSubTrades.args[1][0]).to.equal("LTCBTC");
            expect(instance._sendSubTrades.args[1][1]).to.be.an("object");
        });
    });

    describe("on duplicate subscribe", () => {
        it("should not send subscribe to the socket", () => {
            instance.subscribeTrades({ id: "LTCBTC" });
            expect(instance._sendSubTrades.callCount).to.equal(2);
        });
    });

    describe("on message", () => {
        before(() => {
            instance._wss.mockEmit("message", "test");
        });
        it("should call on message", () => {
            expect(instance._onMessage.args[0][0]).to.equal("test");
        });
    });

    describe("on reconnect", () => {
        it("should resubscribe to markets", () => {
            instance._wss.mockEmit("connected");
            expect(instance._sendSubTrades.callCount).to.equal(4);
            expect(instance._sendSubTrades.args[2][0]).to.equal("BTCUSD");
            expect(instance._sendSubTrades.args[2][1]).to.be.an("object");
            expect(instance._sendSubTrades.args[3][0]).to.equal("LTCBTC");
            expect(instance._sendSubTrades.args[3][1]).to.be.an("object");
        });
    });

    describe("on unsubscribe", () => {
        it("should send unsubscribe to socket", () => {
            instance.unsubscribeTrades({ id: "LTCBTC" });
            expect(instance._sendUnsubTrades.callCount).to.equal(1);
            expect(instance._sendUnsubTrades.args[0][0]).to.equal("LTCBTC");
            expect(instance._sendUnsubTrades.args[0][1]).to.be.an("object");
        });
    });

    describe("on duplicate unsubscribe", () => {
        it("should not send unsubscribe to the socket", () => {
            instance.unsubscribeTrades({ id: "LTCBTC" });
            expect(instance._sendUnsubTrades.callCount).to.equal(1);
        });
    });

    describe("when no messages received", () => {
        let originalWss;
        const closingEvent = sinon.stub();
        const closedEvent = sinon.stub();
        const reconnectingEvent = sinon.stub();

        before(async () => {
            originalWss = instance._wss;
            instance.on("closing", closingEvent);
            instance.on("closed", closedEvent);
            instance.on("reconnecting", reconnectingEvent);
            instance.emit("trade"); // triggers the connection watcher
            instance._watcher._reconnect();
        });

        it("should close the connection", () => {
            expect(originalWss.close.callCount).to.equal(1);
        });

        it("should emit a closing event", () => {
            expect(closingEvent.callCount).to.equal(1);
        });

        it("should emit a closed event", () => {
            expect(closedEvent.callCount).to.equal(1);
        });

        it("should reopen the connection", () => {
            expect(instance._wss).to.not.deep.equal(originalWss);
            expect(instance._wss.connect.callCount).to.equal(1);
        });

        it("should emit a reconnected event", () => {
            expect(reconnectingEvent.callCount).to.equal(1);
        });
    });

    describe("when connected, on disconnect", () => {
        it("disconnect event should fire if the underlying socket closes", done => {
            instance._watcher.stop.resetHistory();
            instance.on("disconnected", done);
            instance._wss.mockEmit("disconnected");
        });

        it("close should stop the reconnection checker", () => {
            expect(instance._watcher.stop.callCount).to.equal(1);
        });
    });

    describe("when connected, .close", () => {
        it("close should emit 'closing' and 'closed' events", done => {
            instance._watcher.stop.resetHistory();
            let closing = false;
            instance.on("closing", () => {
                closing = true;
            });
            instance.on("closed", () => {
                instance.removeAllListeners();
                if (closing) done();
            });
            instance.close();
        });

        it("close should stop the reconnection checker", () => {
            expect(instance._watcher.stop.callCount).to.equal(2);
        });
    });

    describe("when already closed", () => {
        it("should not 'closing' and 'closed' events", () => {
            instance.on("closing", () => {
                throw new Error("should not reach here");
            });
            instance.on("closed", () => {
                throw new Error("should not reach here");
            });
            instance.close();
        });
    });

    describe("level2 snapshots", () => {
        let instance;

        before(() => {
            instance = buildInstance();
            instance._connect();
        });

        describe("on first subscribe", () => {
            it("should open a connection", () => {
                instance.subscribeLevel2Snapshots({ id: "BTCUSD" });
                expect(instance._wss).to.not.be.undefined;
                expect(instance._wss.connect.callCount).to.equal(1);
            });
            it("should send subscribe to the socket", () => {
                instance._wss.mockEmit("connected");
                expect(instance._sendSubLevel2Snapshots.callCount).to.equal(1);
                expect(instance._sendSubLevel2Snapshots.args[0][0]).to.equal("BTCUSD");
                expect(instance._sendSubLevel2Snapshots.args[0][1]).to.be.an("object");
            });
            it("should start the reconnectChecker", () => {
                expect(instance._watcher.start.callCount).to.equal(1);
            });
        });

        describe("on subsequent subscribes", () => {
            it("should not connect again", () => {
                instance.subscribeLevel2Snapshots({ id: "LTCBTC" });
                expect(instance._wss.connect.callCount).to.equal(1);
            });
            it("should send subscribe to the socket", () => {
                expect(instance._sendSubLevel2Snapshots.callCount).to.equal(2);
                expect(instance._sendSubLevel2Snapshots.args[1][0]).to.equal("LTCBTC");
                expect(instance._sendSubLevel2Snapshots.args[1][1]).to.be.an("object");
            });
        });

        describe("on unsubscribe", () => {
            it("should send unsubscribe to socket", () => {
                instance.unsubscribeLevel2Snapshots({ id: "LTCBTC" });
                expect(instance._sendUnsubLevel2Snapshots.callCount).to.equal(1);
                expect(instance._sendUnsubLevel2Snapshots.args[0][0]).to.equal("LTCBTC");
                expect(instance._sendUnsubLevel2Snapshots.args[0][1]).to.be.an("object");
            });
        });
    });

    describe("level2 updates", () => {
        let instance;

        before(() => {
            instance = buildInstance();
            instance._connect();
        });

        describe("on first subscribe", () => {
            it("should open a connection", () => {
                instance.subscribeLevel2Updates({ id: "BTCUSD" });
                expect(instance._wss).to.not.be.undefined;
                expect(instance._wss.connect.callCount).to.equal(1);
            });
            it("should send subscribe to the socket", () => {
                instance._wss.mockEmit("connected");
                expect(instance._sendSubLevel2Updates.callCount).to.equal(1);
                expect(instance._sendSubLevel2Updates.args[0][0]).to.equal("BTCUSD");
                expect(instance._sendSubLevel2Updates.args[0][1]).to.be.an("object");
            });
            it("should start the reconnectChecker", () => {
                expect(instance._watcher.start.callCount).to.equal(1);
            });
        });

        describe("on subsequent subscribes", () => {
            it("should not connect again", () => {
                instance.subscribeLevel2Updates({ id: "LTCBTC" });
                expect(instance._wss.connect.callCount).to.equal(1);
            });
            it("should send subscribe to the socket", () => {
                expect(instance._sendSubLevel2Updates.callCount).to.equal(2);
                expect(instance._sendSubLevel2Updates.args[1][0]).to.equal("LTCBTC");
                expect(instance._sendSubLevel2Updates.args[1][1]).to.be.an("object");
            });
        });

        describe("on unsubscribe", () => {
            it("should send unsubscribe to socket", () => {
                instance.unsubscribeLevel2Updates({ id: "LTCBTC" });
                expect(instance._sendUnsubLevel2Updates.callCount).to.equal(1);
                expect(instance._sendUnsubLevel2Updates.args[0][0]).to.equal("LTCBTC");
            });
        });
    });

    describe("level3 updates", () => {
        let instance;

        before(() => {
            instance = buildInstance();
            instance._connect();
        });

        describe("on first subscribe", () => {
            it("should open a connection", () => {
                instance.subscribeLevel3Updates({ id: "BTCUSD" });
                expect(instance._wss).to.not.be.undefined;
                expect(instance._wss.connect.callCount).to.equal(1);
            });
            it("should send subscribe to the socket", () => {
                instance._wss.mockEmit("connected");
                expect(instance._sendSubLevel3Updates.callCount).to.equal(1);
                expect(instance._sendSubLevel3Updates.args[0][0]).to.equal("BTCUSD");
                expect(instance._sendSubLevel3Updates.args[0][1]).to.be.an("object");
            });
            it("should start the reconnectChecker", () => {
                expect(instance._watcher.start.callCount).to.equal(1);
            });
        });

        describe("on subsequent subscribes", () => {
            it("should not connect again", () => {
                instance.subscribeLevel3Updates({ id: "LTCBTC" });
                expect(instance._wss.connect.callCount).to.equal(1);
            });
            it("should send subscribe to the socket", () => {
                expect(instance._sendSubLevel3Updates.callCount).to.equal(2);
                expect(instance._sendSubLevel3Updates.args[1][0]).to.equal("LTCBTC");
                expect(instance._sendSubLevel3Updates.args[1][1]).to.be.an("object");
            });
        });

        describe("on unsubscribe", () => {
            it("should send unsubscribe to socket", () => {
                instance.unsubscribeLevel3Updates({ id: "LTCBTC" });
                expect(instance._sendUnsubLevel3Updates.callCount).to.equal(1);
                expect(instance._sendUnsubLevel3Updates.args[0][0]).to.equal("LTCBTC");
            });
        });
    });

    describe("ticker", () => {
        let instance;

        before(() => {
            instance = buildInstance();
            instance._connect();
        });

        describe("on first subscribe", () => {
            it("should open a connection", () => {
                instance.subscribeTicker({ id: "BTCUSD" });
                expect(instance._wss).to.not.be.undefined;
                expect(instance._wss.connect.callCount).to.equal(1);
            });
            it("should send subscribe to the socket", () => {
                instance._wss.mockEmit("connected");
                expect(instance._sendSubTicker.callCount).to.equal(1);
                expect(instance._sendSubTicker.args[0][0]).to.equal("BTCUSD");
                expect(instance._sendSubTicker.args[0][1]).to.be.an("object");
            });
            it("should start the reconnectChecker", () => {
                expect(instance._watcher.start.callCount).to.equal(1);
            });
        });

        describe("on subsequent subscribes", () => {
            it("should not connect again", () => {
                instance.subscribeTicker({ id: "LTCBTC" });
                expect(instance._wss.connect.callCount).to.equal(1);
            });
            it("should send subscribe to the socket", () => {
                expect(instance._sendSubTicker.callCount).to.equal(2);
                expect(instance._sendSubTicker.args[1][0]).to.equal("LTCBTC");
                expect(instance._sendSubTicker.args[1][1]).to.be.an("object");
            });
        });

        // describe("on unsubscribe", () => {
        //   it("should send unsubscribe to socket", () => {
        //     instance.unsubscribeTicker({ id: "LTCBTC" });
        //     expect(instance._sendUnsubTicker.callCount).to.equal(1);
        //     expect(instance._sendUnsubTicker.args[0][0]).to.equal("LTCBTC");
        //   });
        // });
    });

    describe("candle", () => {
        let instance;

        before(() => {
            instance = buildInstance();
            instance._connect();
        });

        describe("on first subscribe", () => {
            it("should open a connection", () => {
                instance.subscribeCandles({ id: "BTCUSD" });
                expect(instance._wss).to.not.be.undefined;
                expect(instance._wss.connect.callCount).to.equal(1);
            });
            it("should send subscribe to the socket", () => {
                instance._wss.mockEmit("connected");
                expect(instance._sendSubCandles.callCount).to.equal(1);
                expect(instance._sendSubCandles.args[0][0]).to.equal("BTCUSD");
                expect(instance._sendSubCandles.args[0][1]).to.be.an("object");
            });
            it("should start the reconnectChecker", () => {
                expect(instance._watcher.start.callCount).to.equal(1);
            });
        });

        describe("on subsequent subscribes", () => {
            it("should not connect again", () => {
                instance.subscribeCandles({ id: "LTCBTC" });
                expect(instance._wss.connect.callCount).to.equal(1);
            });
            it("should send subscribe to the socket", () => {
                expect(instance._sendSubCandles.callCount).to.equal(2);
                expect(instance._sendSubCandles.args[1][0]).to.equal("LTCBTC");
                expect(instance._sendSubCandles.args[1][1]).to.be.an("object");
            });
        });

        describe("on unsubscribe", () => {
            it("should send unsubscribe to socket", () => {
                instance.unsubscribeCandles({ id: "LTCBTC" });
                expect(instance._sendUnsubCandles.callCount).to.equal(1);
                expect(instance._sendUnsubCandles.args[0][0]).to.equal("LTCBTC");
            });
        });
    });

    describe("neutered should no-op", () => {
        let instance;
        const market = { id: "BTCUSD" };

        before(() => {
            instance = buildInstance();
            instance.hasTickers = false;
            instance.hasTrades = false;
            instance.hasLevel2Snapshots = false;
            instance.hasLevel2Updates = false;
            instance.hasLevel3Updates = false;
            instance._connect();
            instance._wss.mockEmit("connected");
        });

        it("should not send ticker sub", () => {
            instance.subscribeTicker(market);
            expect(instance._sendSubTicker.callCount).to.equal(0);
        });

        it("should not send trade sub", () => {
            instance.subscribeTrades(market);
            expect(instance._sendSubTrades.callCount).to.equal(0);
        });
        it("should not send trade unsub", () => {
            instance.unsubscribeTrades(market);
            expect(instance._sendUnsubTrades.callCount).to.equal(0);
        });
        it("should not send level2 snapshot sub", () => {
            instance.subscribeLevel2Snapshots(market);
            expect(instance._sendSubLevel2Snapshots.callCount).to.equal(0);
        });
        it("should not send level2 snapshot unsub", () => {
            instance.unsubscribeLevel2Snapshots(market);
            expect(instance._sendUnsubLevel2Snapshots.callCount).to.equal(0);
        });
        it("should not send level2 update sub", () => {
            instance.subscribeLevel2Updates(market);
            expect(instance._sendSubLevel2Updates.callCount).to.equal(0);
        });
        it("should not send level2 update unsub", () => {
            instance.unsubscribeLevel2Updates(market);
            expect(instance._sendUnsubLevel2Updates.callCount).to.equal(0);
        });
        it("should not send level3 update sub", () => {
            instance.subscribeLevel3Updates(market);
            expect(instance._sendSubLevel3Updates.callCount).to.equal(0);
        });
        it("should not send level3 update unsub", () => {
            instance.unsubscribeLevel3Updates(market);
            expect(instance._sendUnsubLevel3Updates.callCount).to.equal(0);
        });
    });
});