Strategy options based on req

[neemah]

Hello, thanks for library, it works like a charm.

But there is one problem we are currently facing – we need to configurate strategy based on req data.

Currently:

new wsfedsaml2({
	// ADFS RP identifier
	realm: 'urn:node:wsfedapp',
	identityProviderUrl: 'https://my-adfs/adfs/ls',
	// ADFS token signing certificate
	thumbprint: '5D27....D27E'
	// or cert: fs.readFileSync("adfs_signing_key.cer")
}, function (profile, done) {
 // ...
}))

And we need:

const getParams = req => {
   return {
     .... req based params
   }
}

new wsfedsaml2(getParams, function (profile, done) {
 // ...
}))

How do we achieve that?

[neemah]

This is how we "patched" strategy to use it in multihost environment (SaaS like ours):

const _ = require('lodash');
const url = require('url');
const { Strategy: Wsfedsaml2 } = require('passport-wsfed-saml2');

class WsfedSaml2Strategy extends Wsfedsaml2 {
  constructor (getConfiguration, verify) {
    if (!_.isFunction(getConfiguration)) {
      throw new Error('Please provide a finder method');
    }
    super({
      cert: '=' // for saml base64 checking in constructor
    }, verify);
    this._getConfiguration = getConfiguration;
  }

  authenticate (req, options = {}) {
    this._getConfiguration(req, (err, configuration) => {
      if (err) {
        return this.fail(err);
      }
      this.options = configuration;
      this.options.protocol = this.options.protocol || 'wsfed';
      this._passReqToCallback = !!configuration.passReqToCallback;
      this._saml = new this._saml.constructor(this.options);
      this._samlp = new this._samlp.constructor(this.options, this._saml);
      this._wsfed.realm = configuration.realm;
      this._wsfed.homerealm = configuration.homerealm;
      this._wsfed.identityProviderUrl = configuration.identityProviderUrl;
      this._wsfed.wreply = configuration.wreply;

      this._key = configuration.sessionKey || `${this.options.protocol}:${url.parse(configuration.identityProviderUrl || '').hostname}`;
      // this is not fully wrap original configuration
      // store, state and eventEmitter are not overrided - see this https://github.com/auth0/passport-wsfed-saml2/blob/master/lib/passport-wsfed-saml2/strategy.js#L48
      return super.authenticate(req, options);
    });
  }
}

module.exports = { Strategy: WsfedSaml2Strategy };