@house-agency/brewtils/test/retry.js

The Brewery Node.js Utilities (brewtils)

const expect = require('chai').expect;
const log = require('../log');
const q = require('q');
const retry = require('../retry');

describe('Retry', () => {
    before(() => {
        log.level('fatal');
    });

    it('shall success', () => {
        var invoked = 0;

        const func = function named_func() {
            invoked++;
            return q(true);
        };

        return retry(func)
        .then(value => {
            expect(value).to.be.true;
            expect(invoked).to.equal(1);
        });
    });

    it('shall success after three retries with a 300 msec delay', () => {
        var invoked = 0;
        const time = (new Date()).getTime();

        const func = function named_func() {
            invoked++;

            return q.try(() => {
                if (invoked < 3) {
                    throw Error('Expected error');
                }

                return true;
            });
        };

        return retry(func, null, 300)
        .then(value => {
            expect(value).to.be.true;
            expect(invoked).to.equal(3);
            expect(time + (300 * 2)).to.be.below((new Date()).getTime());
        });
    });

    it('shall fail after four retries with a 100 msec delay', () => {
        var invoked = 0;
        const time = (new Date()).getTime();

        const func = function named_func() {
            invoked++;

            return q.try(() => {
                throw Error('Expected error');
            });
        };

        return retry(func, 4)
        .then(() => {
            throw new Error('Shall not happen');
        })
        .catch(error => {
            expect(error.message).to.equal('Expected error');
            expect(invoked).to.equal(4);
            expect(time + (100 * 3)).to.be.below((new Date()).getTime());
        });
    });

    it('shall not accept a specific error and retry otherwise', () => {
        var invoked = 0;
        const time = (new Date()).getTime();

        const func = function named_func() {
            invoked++;

            return q.try(() => {

                if(invoked < 4) 
                    throw Error('Expected error');
                else
                    throw Error('Filtered error');
            });
        };

        //Returns true when should be retried
        const filter_func = function error_func(error) {
            if(error.message === 'Filtered error')
                return false;
            else 
                return true;
        };

        return retry(func, 4, 300, filter_func)
        .then(() => {
            throw new Error('Shall not happen');
        })
        .catch(error => {
            expect(error.message).to.equal('Filtered error');
            expect(invoked).to.equal(4);
            expect(time + (100 * 3)).to.be.below((new Date()).getTime());
        });
    });

});