index.js

'use strict';

const biscuit = require('@biscuit-auth/biscuit-wasm')

module.exports = function(options) {
  const publicKey = biscuit.PublicKey.from_hex(options.publicKey)

  var middleware = function(req, res, next) {
    try {
      const authHeader = req.headers.authorization;

      var authorizer = new biscuit.Authorizer()

      console.log("created authorizer")
      if(options.policies !== undefined) {
        authorizer.add_code(options.policies)
        console.log("added code")
      }

      if(authHeader !== undefined) {
        const token = biscuit.Biscuit.from_base64(authHeader, publicKey)
        authorizer.add_token(token)
        console.log("added token")
      }

      if(options.extractor !== undefined) {
        console.log("will call extractor")
        options.extractor(req, authorizer)
      }

      console.log("will authorize")
      const res = authorizer.authorize()
      console.log("ok")
      next()
    } catch(error) {
      //console.log("not authorized: "+authorizer.print())
      console.log("error: "+JSON.stringify(error))
      return res.status(403).json({
        status: 403,
        message: 'FORBIDDEN'
      })
    }
  }

  return middleware;
};

module.exports.fact = function fact(strings, ...keys) {
  let template = ""
  for (let i = 0; i < strings.length; i++) {
    template += strings[i]

    if(i < keys.length) {
      template += "$"+i
    }

    console.log("constructed: "+template)
  }

  let fact = biscuit.Fact.from_str(template)
  for (let i = 0; i < keys.length; ++i) {
    fact.set(""+i, keys[i])
  }

  return fact
}

module.exports.rule = function rule(strings, ...keys) {
  let template = ""
  for (let i = 0; i < strings.length; i++) {
    template += strings[i]

    if(i < keys.length) {
      template += "$"+i
    }
  }

  let rule = biscuit.Rule.from_str(template)
  for (let i = 0; i < keys.length; ++i) {
    rule.set(""+i, keys[i])
  }

  return rule
}

module.exports.check = function check(strings, ...keys) {
  let template = ""
  for (let i = 0; i < strings.length; i++) {
    template += strings[i]

    if(i < keys.length) {
      template += "$"+i
    }
  }

  let check = biscuit.Check.from_str(template)
  for (let i = 0; i < keys.length; ++i) {
    check.set(""+i, keys[i])
  }

  return check
}

module.exports.policy = function policy(strings, ...keys) {
  let template = ""
  for (let i = 0; i < strings.length; i++) {
    template += strings[i]

    if(i < keys.length) {
      template += "$"+i
    }
  }

  let policy = biscuit.Policy.from_str(template)
  for (let i = 0; i < keys.length; ++i) {
    policy.set(""+i, keys[i])
  }

  return policy
}