travopti/backend/models/transformer.js
2020-06-17 21:50:20 +02:00

77 lines
2.1 KiB
JavaScript

const _ = require('lodash')
const fs = require('fs')
exports.transform = (data) => {
// get data
// let data = JSON.parse(fs.readFileSync('transformer-test.json'));
const types = Object.keys(data[0].scores)
// STEP 1 Create Response Array with region names from first climate object
let byRegion = data[0].climate.map(el => {
return {
region_id: el.region_id,
country_id: el.country_id,
name: el.name,
}
})
// STEP 2 Prepare flat scoreobject array and set days property
scoreObjs = _.flatten(_.map(data, (period) => {
return _.reduce(period.scores, (arr, el) => {
return arr.concat(el)
}).map(element => {
element.days = period.days
return element
})
}))
// STEP 3 Collect scoreobjects for each region
let results = byRegion.map(region => {
let scores = []
types.forEach(typ => {
let tempScores = _.filter(scoreObjs, { 'region_id': region.region_id, 'type': typ })
if (_.some(tempScores, { 'score': null })) {
console.log("found 'null' scores! skipping...")
//console.log(tempScores)
return
}
let averagedScore = {
region_id: region.region_id,
type: typ,
value: 0,
score: 0,
days: 0
}
tempScores.forEach(el => {
averagedScore.value += (el.value * el.days)
averagedScore.score += (el.score * el.days)
averagedScore.days += (el.days)
})
averagedScore.value = _.round(averagedScore.value / averagedScore.days, 1)
averagedScore.score = _.round(averagedScore.score / averagedScore.days, 1)
delete averagedScore.region_id
delete averagedScore.days
scores.push(averagedScore)
})
region.scores = scores
// STEP 4 Calculate Average Score
region.score = calculateAverage(region.scores)
//console.log(region)
return region
})
// console.log(results)
return _.orderBy(results, 'score', 'desc')
//end
}
function calculateAverage(scores) {
let sum = 0
scores.forEach(el => sum += el.score)
//console.log(sum)
return _.round(sum / scores.length, 2)
}