serverless-offline/src/events/http/javaHelpers.js

Emulate AWS λ and API Gateway locally when developing your Serverless project

// String functions
// For velocity templates to access java functions, to mimick AWS

function javaContains(value) {
  return this.includes(value)
}

function javaEquals(anObject) {
  return this.toString() === anObject.toString()
}

function javaEqualsIgnoreCase(anotherString) {
  return anotherString === null
    ? false
    : this === anotherString ||
        this.toLowerCase() === anotherString.toLowerCase()
}

function javaMatches(value) {
  return this.match(new RegExp(value, "m"))
}

function javaReplaceFirst(oldValue, newValue) {
  return this.replace(new RegExp(oldValue, "m"), newValue)
}

// method has 2 function signatures:
// regionMatches(toffset: number, other: string, ooffset: number, len: number): boolean
// regionMatches(ignoreCase: boolean, toffset: number, other: string, ooffset: number, len: number): boolean
function javaRegionMatches(...args) {
  let ignoreCase
  let toffset
  let other
  let ooffset
  let len

  if (args.length === 4) {
    ;[toffset, other, ooffset, len] = args
    ignoreCase = false
  } else {
    ;[ignoreCase, toffset, other, ooffset, len] = args
  }

  // Note: toffset, ooffset, or len might be near -1>>>1.
  if (
    ooffset < 0 ||
    toffset < 0 ||
    toffset > this.length - len ||
    ooffset > other.length - len
  ) {
    return false
  }

  let s1 = this.substring(toffset, toffset + len)
  let s2 = other.substring(ooffset, ooffset + len)

  if (ignoreCase) {
    s1 = s1.toLowerCase()
    s2 = s2.toLowerCase()
  }

  return s1 === s2
}

const {
  prototype,
  prototype: {
    contains,
    equals,
    equalsIgnoreCase,
    matches,
    regionMatches,
    replaceFirst,
  },
} = String

export default function runInPollutedScope(runScope) {
  prototype.contains = javaContains
  prototype.equals = javaEquals
  prototype.equalsIgnoreCase = javaEqualsIgnoreCase
  prototype.matches = javaMatches
  prototype.regionMatches = javaRegionMatches
  prototype.replaceFirst = javaReplaceFirst

  const result = runScope()

  prototype.contains = contains
  prototype.equals = equals
  prototype.equalsIgnoreCase = equalsIgnoreCase
  prototype.matches = matches
  prototype.regionMatches = regionMatches
  prototype.replaceFirst = replaceFirst

  return result
}