refactor: rename worker choice strategies to sensible names

[poolifier.git] / tests / pools / selection-strategies / worker-choice-strategy-context.test.js

const { expect } = require('expect')
const sinon = require('sinon')
const {
  FixedThreadPool,
  DynamicThreadPool,
  WorkerChoiceStrategies
} = require('../../../lib')
const {
  WorkerChoiceStrategyContext
} = require('../../../lib/pools/selection-strategies/worker-choice-strategy-context')
const {
  RoundRobinWorkerChoiceStrategy
} = require('../../../lib/pools/selection-strategies/round-robin-worker-choice-strategy')
const {
  LeastUsedWorkerChoiceStrategy
} = require('../../../lib/pools/selection-strategies/least-used-worker-choice-strategy')
const {
  LeastBusyWorkerChoiceStrategy
} = require('../../../lib/pools/selection-strategies/least-busy-worker-choice-strategy')
const {
  FairShareWorkerChoiceStrategy
} = require('../../../lib/pools/selection-strategies/fair-share-worker-choice-strategy')
const {
  WeightedRoundRobinWorkerChoiceStrategy
} = require('../../../lib/pools/selection-strategies/weighted-round-robin-worker-choice-strategy')

describe('Worker choice strategy context test suite', () => {
  const min = 1
  const max = 3
  let fixedPool, dynamicPool

  before(() => {
    fixedPool = new FixedThreadPool(
      max,
      './tests/worker-files/thread/testWorker.js'
    )
    dynamicPool = new DynamicThreadPool(
      min,
      max,
      './tests/worker-files/thread/testWorker.js'
    )
  })

  afterEach(() => {
    sinon.restore()
  })

  after(async () => {
    await fixedPool.destroy()
    await dynamicPool.destroy()
  })

  it('Verify that constructor() initializes the context with all the available worker choice strategies', () => {
    const workerChoiceStrategyContext = new WorkerChoiceStrategyContext(
      fixedPool
    )
    expect(workerChoiceStrategyContext.workerChoiceStrategies.size).toBe(
      Object.keys(WorkerChoiceStrategies).length
    )
  })

  it('Verify that execute() return the worker chosen by the strategy with fixed pool', () => {
    const workerChoiceStrategyContext = new WorkerChoiceStrategyContext(
      fixedPool
    )
    const WorkerChoiceStrategyStub = sinon.createStubInstance(
      RoundRobinWorkerChoiceStrategy,
      {
        choose: sinon.stub().returns(0)
      }
    )
    expect(workerChoiceStrategyContext.workerChoiceStrategy).toBe(
      WorkerChoiceStrategies.ROUND_ROBIN
    )
    workerChoiceStrategyContext.workerChoiceStrategies.set(
      workerChoiceStrategyContext.workerChoiceStrategy,
      WorkerChoiceStrategyStub
    )
    const chosenWorkerKey = workerChoiceStrategyContext.execute()
    expect(
      workerChoiceStrategyContext.workerChoiceStrategies.get(
        workerChoiceStrategyContext.workerChoiceStrategy
      ).choose.calledOnce
    ).toBe(true)
    expect(chosenWorkerKey).toBe(0)
  })

  it('Verify that execute() throws error if null or undefined is returned', () => {
    const workerChoiceStrategyContext = new WorkerChoiceStrategyContext(
      fixedPool
    )
    const WorkerChoiceStrategyUndefinedStub = sinon.createStubInstance(
      RoundRobinWorkerChoiceStrategy,
      {
        choose: sinon.stub().returns(undefined)
      }
    )
    const WorkerChoiceStrategyNullStub = sinon.createStubInstance(
      RoundRobinWorkerChoiceStrategy,
      {
        choose: sinon.stub().returns(null)
      }
    )
    expect(workerChoiceStrategyContext.workerChoiceStrategy).toBe(
      WorkerChoiceStrategies.ROUND_ROBIN
    )
    workerChoiceStrategyContext.workerChoiceStrategies.set(
      workerChoiceStrategyContext.workerChoiceStrategy,
      WorkerChoiceStrategyUndefinedStub
    )
    expect(() => workerChoiceStrategyContext.execute()).toThrowError(
      new Error('Worker node key chosen is null or undefined')
    )
    workerChoiceStrategyContext.workerChoiceStrategies.set(
      workerChoiceStrategyContext.workerChoiceStrategy,
      WorkerChoiceStrategyNullStub
    )
    expect(() => workerChoiceStrategyContext.execute()).toThrowError(
      new Error('Worker node key chosen is null or undefined')
    )
  })

  it('Verify that execute() return the worker chosen by the strategy with dynamic pool', () => {
    const workerChoiceStrategyContext = new WorkerChoiceStrategyContext(
      dynamicPool
    )
    const WorkerChoiceStrategyStub = sinon.createStubInstance(
      RoundRobinWorkerChoiceStrategy,
      {
        choose: sinon.stub().returns(0)
      }
    )
    expect(workerChoiceStrategyContext.workerChoiceStrategy).toBe(
      WorkerChoiceStrategies.ROUND_ROBIN
    )
    workerChoiceStrategyContext.workerChoiceStrategies.set(
      workerChoiceStrategyContext.workerChoiceStrategy,
      WorkerChoiceStrategyStub
    )
    const chosenWorkerKey = workerChoiceStrategyContext.execute()
    expect(
      workerChoiceStrategyContext.workerChoiceStrategies.get(
        workerChoiceStrategyContext.workerChoiceStrategy
      ).choose.calledOnce
    ).toBe(true)
    expect(chosenWorkerKey).toBe(0)
  })

  it('Verify that setWorkerChoiceStrategy() works with ROUND_ROBIN and fixed pool', () => {
    const workerChoiceStrategy = WorkerChoiceStrategies.ROUND_ROBIN
    const workerChoiceStrategyContext = new WorkerChoiceStrategyContext(
      fixedPool
    )
    expect(
      workerChoiceStrategyContext.workerChoiceStrategies.get(
        workerChoiceStrategy
      )
    ).toBeInstanceOf(RoundRobinWorkerChoiceStrategy)
    expect(workerChoiceStrategyContext.workerChoiceStrategy).toBe(
      workerChoiceStrategy
    )
    workerChoiceStrategyContext.setWorkerChoiceStrategy(workerChoiceStrategy)
    expect(
      workerChoiceStrategyContext.workerChoiceStrategies.get(
        workerChoiceStrategy
      )
    ).toBeInstanceOf(RoundRobinWorkerChoiceStrategy)
    expect(workerChoiceStrategyContext.workerChoiceStrategy).toBe(
      workerChoiceStrategy
    )
  })

  it('Verify that setWorkerChoiceStrategy() works with ROUND_ROBIN and dynamic pool', () => {
    const workerChoiceStrategy = WorkerChoiceStrategies.ROUND_ROBIN
    const workerChoiceStrategyContext = new WorkerChoiceStrategyContext(
      dynamicPool
    )
    expect(
      workerChoiceStrategyContext.workerChoiceStrategies.get(
        workerChoiceStrategy
      )
    ).toBeInstanceOf(RoundRobinWorkerChoiceStrategy)
    expect(workerChoiceStrategyContext.workerChoiceStrategy).toBe(
      workerChoiceStrategy
    )
    workerChoiceStrategyContext.setWorkerChoiceStrategy(workerChoiceStrategy)
    expect(
      workerChoiceStrategyContext.workerChoiceStrategies.get(
        workerChoiceStrategy
      )
    ).toBeInstanceOf(RoundRobinWorkerChoiceStrategy)
    expect(workerChoiceStrategyContext.workerChoiceStrategy).toBe(
      workerChoiceStrategy
    )
  })

  it('Verify that setWorkerChoiceStrategy() works with LEAST_USED and fixed pool', () => {
    const workerChoiceStrategy = WorkerChoiceStrategies.LEAST_USED
    const workerChoiceStrategyContext = new WorkerChoiceStrategyContext(
      fixedPool
    )
    workerChoiceStrategyContext.setWorkerChoiceStrategy(workerChoiceStrategy)
    expect(
      workerChoiceStrategyContext.workerChoiceStrategies.get(
        workerChoiceStrategy
      )
    ).toBeInstanceOf(LeastUsedWorkerChoiceStrategy)
    expect(workerChoiceStrategyContext.workerChoiceStrategy).toBe(
      workerChoiceStrategy
    )
  })

  it('Verify that setWorkerChoiceStrategy() works with LEAST_USED and dynamic pool', () => {
    const workerChoiceStrategy = WorkerChoiceStrategies.LEAST_USED
    const workerChoiceStrategyContext = new WorkerChoiceStrategyContext(
      dynamicPool
    )
    workerChoiceStrategyContext.setWorkerChoiceStrategy(workerChoiceStrategy)
    expect(
      workerChoiceStrategyContext.workerChoiceStrategies.get(
        workerChoiceStrategy
      )
    ).toBeInstanceOf(LeastUsedWorkerChoiceStrategy)
    expect(workerChoiceStrategyContext.workerChoiceStrategy).toBe(
      workerChoiceStrategy
    )
  })

  it('Verify that setWorkerChoiceStrategy() works with LEAST_BUSY and fixed pool', () => {
    const workerChoiceStrategy = WorkerChoiceStrategies.LEAST_BUSY
    const workerChoiceStrategyContext = new WorkerChoiceStrategyContext(
      fixedPool
    )
    workerChoiceStrategyContext.setWorkerChoiceStrategy(workerChoiceStrategy)
    expect(
      workerChoiceStrategyContext.workerChoiceStrategies.get(
        workerChoiceStrategy
      )
    ).toBeInstanceOf(LeastBusyWorkerChoiceStrategy)
    expect(workerChoiceStrategyContext.workerChoiceStrategy).toBe(
      workerChoiceStrategy
    )
  })

  it('Verify that setWorkerChoiceStrategy() works with LEAST_BUSY and dynamic pool', () => {
    const workerChoiceStrategy = WorkerChoiceStrategies.LEAST_BUSY
    const workerChoiceStrategyContext = new WorkerChoiceStrategyContext(
      dynamicPool
    )
    workerChoiceStrategyContext.setWorkerChoiceStrategy(workerChoiceStrategy)
    expect(
      workerChoiceStrategyContext.workerChoiceStrategies.get(
        workerChoiceStrategy
      )
    ).toBeInstanceOf(LeastBusyWorkerChoiceStrategy)
    expect(workerChoiceStrategyContext.workerChoiceStrategy).toBe(
      workerChoiceStrategy
    )
  })

  it('Verify that setWorkerChoiceStrategy() works with FAIR_SHARE and fixed pool', () => {
    const workerChoiceStrategy = WorkerChoiceStrategies.FAIR_SHARE
    const workerChoiceStrategyContext = new WorkerChoiceStrategyContext(
      fixedPool
    )
    workerChoiceStrategyContext.setWorkerChoiceStrategy(workerChoiceStrategy)
    expect(
      workerChoiceStrategyContext.workerChoiceStrategies.get(
        workerChoiceStrategy
      )
    ).toBeInstanceOf(FairShareWorkerChoiceStrategy)
    expect(workerChoiceStrategyContext.workerChoiceStrategy).toBe(
      workerChoiceStrategy
    )
  })

  it('Verify that setWorkerChoiceStrategy() works with FAIR_SHARE and dynamic pool', () => {
    const workerChoiceStrategy = WorkerChoiceStrategies.FAIR_SHARE
    const workerChoiceStrategyContext = new WorkerChoiceStrategyContext(
      dynamicPool
    )
    workerChoiceStrategyContext.setWorkerChoiceStrategy(workerChoiceStrategy)
    expect(
      workerChoiceStrategyContext.workerChoiceStrategies.get(
        workerChoiceStrategy
      )
    ).toBeInstanceOf(FairShareWorkerChoiceStrategy)
    expect(workerChoiceStrategyContext.workerChoiceStrategy).toBe(
      workerChoiceStrategy
    )
  })

  it('Verify that setWorkerChoiceStrategy() works with WEIGHTED_ROUND_ROBIN and fixed pool', () => {
    const workerChoiceStrategy = WorkerChoiceStrategies.WEIGHTED_ROUND_ROBIN
    const workerChoiceStrategyContext = new WorkerChoiceStrategyContext(
      fixedPool
    )
    workerChoiceStrategyContext.setWorkerChoiceStrategy(workerChoiceStrategy)
    expect(
      workerChoiceStrategyContext.workerChoiceStrategies.get(
        workerChoiceStrategy
      )
    ).toBeInstanceOf(WeightedRoundRobinWorkerChoiceStrategy)
    expect(workerChoiceStrategyContext.workerChoiceStrategy).toBe(
      workerChoiceStrategy
    )
  })

  it('Verify that setWorkerChoiceStrategy() works with WEIGHTED_ROUND_ROBIN and dynamic pool', () => {
    const workerChoiceStrategy = WorkerChoiceStrategies.WEIGHTED_ROUND_ROBIN
    const workerChoiceStrategyContext = new WorkerChoiceStrategyContext(
      dynamicPool
    )
    workerChoiceStrategyContext.setWorkerChoiceStrategy(workerChoiceStrategy)
    expect(
      workerChoiceStrategyContext.workerChoiceStrategies.get(
        workerChoiceStrategy
      )
    ).toBeInstanceOf(WeightedRoundRobinWorkerChoiceStrategy)
    expect(workerChoiceStrategyContext.workerChoiceStrategy).toBe(
      workerChoiceStrategy
    )
  })

  it('Verify that worker choice strategy options enable median runtime pool statistics', () => {
    const wwrWorkerChoiceStrategy = WorkerChoiceStrategies.WEIGHTED_ROUND_ROBIN
    let workerChoiceStrategyContext = new WorkerChoiceStrategyContext(
      fixedPool,
      wwrWorkerChoiceStrategy,
      {
        medRunTime: true
      }
    )
    expect(workerChoiceStrategyContext.getRequiredStatistics().avgRunTime).toBe(
      false
    )
    expect(workerChoiceStrategyContext.getRequiredStatistics().medRunTime).toBe(
      true
    )
    workerChoiceStrategyContext = new WorkerChoiceStrategyContext(
      dynamicPool,
      wwrWorkerChoiceStrategy,
      {
        medRunTime: true
      }
    )
    expect(workerChoiceStrategyContext.getRequiredStatistics().avgRunTime).toBe(
      false
    )
    expect(workerChoiceStrategyContext.getRequiredStatistics().medRunTime).toBe(
      true
    )
    const fsWorkerChoiceStrategy = WorkerChoiceStrategies.FAIR_SHARE
    workerChoiceStrategyContext = new WorkerChoiceStrategyContext(
      fixedPool,
      fsWorkerChoiceStrategy,
      {
        medRunTime: true
      }
    )
    expect(workerChoiceStrategyContext.getRequiredStatistics().avgRunTime).toBe(
      false
    )
    expect(workerChoiceStrategyContext.getRequiredStatistics().medRunTime).toBe(
      true
    )
    workerChoiceStrategyContext = new WorkerChoiceStrategyContext(
      dynamicPool,
      fsWorkerChoiceStrategy,
      {
        medRunTime: true
      }
    )
    expect(workerChoiceStrategyContext.getRequiredStatistics().avgRunTime).toBe(
      false
    )
    expect(workerChoiceStrategyContext.getRequiredStatistics().medRunTime).toBe(
      true
    )
  })
})