Cheat sheet - JS code snippets

Checking duplicates in an array

// Method 1
function distinct(array) {
  const a = [];
  for (let i = 0, l = array.length; i < l; i++) {
    if (a.indexOf(array[i]) === -1) a.push(array[i]);
  }
  return a;
}

// Method 2
function hasDuplicates(array) {
  const valuesSoFar = Object.create(null);
  for (let i = 0; i < array.length; i++) {
    const value = array[i];
    if (value in valuesSoFar) return true;
    valuesSoFar[value] = true;
  }
  return false;
}

---

Removing empty values from an array

const newArr = arr.filter(el => !!el);

---

Checking duplicates in a JSON object

const listaGrupBezDuplikatow = listaGrup.filter((thing, index, self) =>
  index === self.findIndex(t => JSON.stringify(t) === JSON.stringify(thing))
);

---

Checking whether an array contains an element

if (tablica.indexOf(element) !== -1) {
  return [{ output: "true" }];
} else {
  return [{ output: "false" }];
}

---

Extracting data from a timestamp

const dataUrodzenia = context.getFirstParameter("dataUrodzenia");
let data = parseInt(dataUrodzenia);
data = new Date(data);
const rok = data.getFullYear();
const miesiac = data.getMonth() + 1;
const dzien = data.getDate();

---

Getting today's date

const dateNow = new Date();
const today = `${dateNow.getFullYear()}-${(dateNow.getMonth() + 1)
  .toString()
  .padStart(2, "0")}-${dateNow.getDate().toString().padStart(2, "0")}`;

---

Extracting file names from the UploadFile component

const nazwy = JSON.parse(context.getFirstParameter("zalaczniki"));
const gotowaLista = nazwy.toString();

---

Getting a specific attribute value of a component

const nazwy = context.getData("@GesUploadFile1", "fileNames");
const rozmiary = context.getData("@GesUploadFile1", "totalFilesSize");

---

Removing spaces

let value = context.getFirstParameter("value");
value = value.replace(/\s+/g, "");

---

Matching a value against a mask (regex)

const input = context.getFirstParameter("dokumentTozsamosci");
const regex = /^[a-zA-Z]{3}[0-9]{6}$/;

if (!input.match(regex)) {
  context.log().info("Invalid identity card number");
} else {
  return [];
}

---

Counting occurrences of a given value

const input = context.getParameters("input");
let trueOccurences = 0;

for (let i = 0; i < input.size(); i++) {
  if (input.get(i) === "true") {
    trueOccurences++;
  }
}

---

Checking how many full years have passed

let dataUrodzenia = context.getFirstParameter("dataUrodzenia");

if (dataUrodzenia !== "" && dataUrodzenia !== null) {
  let data = parseInt(dataUrodzenia);
  dataUrodzenia = new Date(data);
  dataUrodzenia.setHours(12, 0, 0, 0);

  const todayDate = new Date();
  todayDate.setHours(12, 0, 0, 0);
  const difference = todayDate.getTime() - dataUrodzenia.getTime();
  const ageDate = new Date(difference);

  if (Math.abs(ageDate.getUTCFullYear() - 1970) >= 18) {
    context.log().info("At least 18 years have passed");
  } else {
    context.log().info("18 years have not passed");
  }
} else {
  return [];
}

---

Retrieving data from a repeatable section

const pesel = context.getParameters("pesel").toArray();
const data = context.getParameters("dataUrodzenia").toArray();

let index = 0;
while (index < 30) {
  const idObywatelstwo =
    "GesComplexComponent2.GesComplexComponent3.GesRepeatableSection2.row" +
    index +
    ".GesComplexComponent2.GesComplexComponent3.GesComplexComponent1.GesCombobox2";

  const ob = context.getData(idObywatelstwo, "label");

  const idImie =
    "GesComplexComponent2.GesComplexComponent3.GesRepeatableSection2.row" +
    index +
    ".GesComplexComponent2.GesComplexComponent3.GesComplexComponent1.GesTextField1";

  const im = context.getData(idImie, "value");

  const isRowVisible = context.isVisible(
    "GesComplexComponent2.GesComplexComponent3.GesRepeatableSection2.row" +
      index +
      ".GesComplexComponent2.GesComplexComponent3.GesComplexComponent1.GesCombobox2"
  );

  if (isRowVisible && im) {
    obywatelstwoList.push(ob);
    stanCywilnyList.push(sc);
    rodzajDokumentuList.push(rd);
  }
  index++;
}

---

Calling ServiceProxy

const input = context.getInputParameters();
let result = context.callService("Plus500ZusAdditionalValueServiceProxy", input);
let parsedResult = JSON.parse(result);

result = result.get(0).get("result");
parsedResult = JSON.parse(result);

---

Creating a dictionary

const items = {
  "Identity card": "DO",
  "Polish passport": "PP",
  "Foreign passport": "PZ",
};

function DictElement(label, value) {
  this.label = label;
  this.value = value;
}

const dict = [];
for (const item in items) {
  dict.push(new DictElement(item, items[item]));
}
return dict;

---

Formatting floating point numbers

function format(interest) {
  return parseFloat(interest)
    .toFixed(2)
    .replace(".", ",")
    .replace(/(?!^)(?=(?:\d{3})+(?:,|$))/gm, " ");
}

---

Returning the day/month/year suffix

function formatDate(unit, quantity) {
  let literal = "days";

  if (unit === "DAY") {
    literal = quantity === 1 ? "day" : "days";
  }

  if (unit === "MONTH") {
    if (quantity === 1) {
      literal = "month";
    } else if (
      quantity < 5 ||
      (quantity > 20 &&
        ["2", "3", "4"].includes(String(quantity).slice(-1)))
    ) {
      literal = "months";
    } else {
      literal = "months";
    }
  }

  if (unit === "YEAR") {
    if (quantity === 1) {
      literal = "year";
    } else if (
      quantity < 5 ||
      (quantity > 20 &&
        ["2", "3", "4"].includes(String(quantity).slice(-1)))
    ) {
      literal = "years";
    } else {
      literal = "years";
    }
  }

  return literal;
}

---

Creating an array from a list of objects

const gotowaListaSchematow = listaSchematowBezDuplikatow.map(
  a => a.schemaId
);

---

Filtering an array

function callService(context) {
  let data = '[{"name":"Jan","lastname":"Kowalski","role":"admin"},{"name":"Adam","lastname":"Pietrzak","role":"user"},{"name":"Karol","lastname":"Kowalski","role":"admin"},{"name":"Joanna","lastname":"Wieczorek","role":"user"}]';
  data = JSON.parse(data);
  data = data.filter(element => element.role === "user");
  return [{ selectedUsersFullListEnd: JSON.stringify(data) }];
}

---

Removing selected properties from an object

// Method 1
function callService(context) {
  let data = '[{"name":"Jan","lastname":"Kowalski","role":"admin"},{"name":"Adam","lastname":"Pietrzak","role":"user"},{"name":"Karol","lastname":"Kowalski","role":"admin"},{"name":"Joanna","lastname":"Wieczorek","role":"user"}]';
  data = JSON.parse(data);
  data = data.map(element => {
    delete element.role;
    return element;
  });
  return [{ selectedUsersFullListEnd: JSON.stringify(data) }];
}

// Method 2
function callService(context) {
  let data = '[{"name":"Jan","lastname":"Kowalski","role":"admin"},{"name":"Adam","lastname":"Pietrzak","role":"user"},{"name":"Karol","lastname":"Kowalski","role":"admin"},{"name":"Joanna","lastname":"Wieczorek","role":"user"}]';
  data = JSON.parse(data);
  for (const element of data) {
    delete element.role;
  }
  return [{ selectedUsersFullListEnd: JSON.stringify(data) }];
}

Removing duplicates from an array using Set

// Values to array
const accountPermissionArr = accountPermissionInput.toArray();

// Set removes duplicates (in JS it preserves insertion order)
const accountPermissionSet = new Set(accountPermissionArr);

// Convert the Set object back to an array
const accountPermissionFinal = Array.from(accountPermissionSet);

// (optionally) if you want to sort the result alphabetically:
// const accountPermissionFinal = Array.from(accountPermissionSet).sort();

---

Getting values using inputParameters

function getSingleValue(valuesMap, paramName, defaultValue) {
  const values = valuesMap.get(paramName);
  if (values != null && !values.isEmpty() && values.get(0) != null) {
    if (values.size() > 1) {
      throw new Error(paramName + " must have single value");
    } else {
      return values.get(0);
    }
  } else {
    return defaultValue;
  }
}

function getBooleanValue(valuesMap, paramName, defaultValue) {
  const value = getSingleValue(valuesMap, paramName, defaultValue);
  return value === true || value === "1" || value === "true";
}

// Usage
const inputParameters = context.getInputParameters();
const onlyVATAccounts = getBooleanValue(inputParameters, "inputOptionalOnlyVATAccounts", false);
const companyNik = getSingleValue(inputParameters, "inputOptionalCompanyNik", null);

---

Creating a BigDecimal and useful helpers

const bigDecimalZero = BigDecimal.valueOf("0").bigDecimal;

function createBigDecimal(value, locale) {
  if (!value) {
    return value;
  }

  let formatValue;

  if (locale === "en") {
    formatValue = value.toString().replace(/,/g, "");
  } else if (locale === "es") {
    formatValue = value.toString().replace(/\./g, "").replace(/,/g, ".");
  } else {
    // default: remove whitespace and replace comma with dot
    formatValue = value.toString().replace(/\s+/g, "").replace(",", ".");
  }

  return BigDecimal.valueOf(formatValue).bigDecimal;
}

function createBigDecimalOrZero(value, locale) {
  return !value ? bigDecimalZero : createBigDecimal(value, locale);
}

function createBigDecimalOrNull(value, locale) {
  return !value ? null : createBigDecimal(value, locale);
}

---

Formatting account balance

const UNBREAKABLE_SPACE = "\u00A0";

function formatAmount(number, locale) {
  const GROUPING_SIZE_OF_BALANCE = 3;
  const NUMBER_OF_FRACTION_DIGITS_IN_BALANCE = 2;

  const localeSettings = {
    en: { groupingSeparator: ",", decimalSeparator: "." },
    pl: { groupingSeparator: UNBREAKABLE_SPACE, decimalSeparator: "," },
    es: { groupingSeparator: ".", decimalSeparator: "," },
  };

  // allow 0, reject null/undefined
  if (number === null || number === undefined) {
    return "";
  }

  const settings = localeSettings[locale] || localeSettings.pl;

  const roundedNumber = Number(number).toFixed(NUMBER_OF_FRACTION_DIGITS_IN_BALANCE);

  const parts = roundedNumber.split(".");
  let integerPart = parts[0];
  const decimalPart = parts[1];

  const regex = new RegExp(`\\B(?=(\\d{${GROUPING_SIZE_OF_BALANCE}})+(?!\\d))`, "g");
  integerPart = integerPart.replace(regex, settings.groupingSeparator);

  return integerPart + settings.decimalSeparator + decimalPart;
}

function getAccountBalanceFormatted(loan, locale) {
  return (
    formatAmount(loan.availableFunds, locale) +
    UNBREAKABLE_SPACE +
    loan.currencyCode
  );
}
// Returns e.g.: "79 561,00 PLN" (PL) or "79,561.00 USD" (EN)

function formatAmountNeutral(value) {
  const formatNeutral = DecimalFormat.of("0.00", DecimalFormatSymbols.EN);
  return value !== null && value !== undefined
    ? formatNeutral.format(BigDecimal.valueOf(value.toString()))
    : "";
}
// Returns neutral format (EN) e.g.: "79561.00"