pagaris/lib/signature.js

Pagaris API client for Node

const Pagaris = require('./pagaris')
const crypto = require('crypto')

class Signature {
  constructor(path, method, body, timestamp = Math.floor(Date.now() / 1000)) {
    this.path = path
    this.method = method
    this.body = body
    if (!this.body) this.body = ''
    this.timestamp = timestamp

    this.value = crypto.createHmac('sha256', (Pagaris.privateKey || ''))
      .update(`${this.timestamp}-${this.method}-${this.path}-${this.body}`)
      .digest('hex')
  }

  headerValue() {
    return `Pagaris ${Pagaris.applicationId}:${this.timestamp}:${this.value}`
  }

  static validate(headerValue, path, body, method = 'POST') {
    const headerRegexp = /^(Pagaris\s)?(.+):(.+):(.+)$/g
    const matches = headerRegexp.exec(headerValue)
    let timestamp = matches && matches[3]
    let signature = matches && matches[4]

    let expected = new Signature(path, method, body, timestamp)
    return expected.value == signature
  }
}

module.exports = Signature