Function start

examples/12-using-custom-almanac.js:37–84

()

}

async function start () {
  const engine = new Engine()
    .addRule({
      conditions: {
        all: [
          {
            fact: 'age',
            params: {
              // the addOne pipe adds one to the value
              pipes: ['addOne']
            },
            operator: 'greaterThanInclusive',
            value: 21
          }
        ]
      },
      event: {
        type: 'Over 21(ish)'
      }
    })

  engine.on('success', async (event, almanac) => {
    const name = await almanac.factValue('name')
    const age = await almanac.factValue('age')
    console.log(`${name} is ${age} years old and ${'is'.green} ${event.type}`)
  })

  engine.on('failure', async (event, almanac) => {
    const name = await almanac.factValue('name')
    const age = await almanac.factValue('age')
    console.log(`${name} is ${age} years old and ${'is not'.red} ${event.type}`)
  })

  const createAlmanacWithPipes = () => {
    const almanac = new PipedAlmanac()
    almanac.addPipe('addOne', (v) => v + 1)
    return almanac
  }

  // first run Bob who is less than 20
  await engine.run({ name: 'Bob', age: 19 }, { almanac: createAlmanacWithPipes() })

  // second run Alice who is 21
  await engine.run({ name: 'Alice', age: 21 }, { almanac: createAlmanacWithPipes() })

  // third run Chad who is 20
  await engine.run({ name: 'Chad', age: 20 }, { almanac: createAlmanacWithPipes() })
}

start()