This module provides a way to use the ims-lti module with Express. It is capable of detecting LTI login requests and intelligently restoring an LTI provider instance from an Express session automatically.
Usage for the module is fairly straightfoward.
var ltiMiddleware = require("express-ims-lti");
var lti = require('ims-lti')
// Optional
// var redisClient = require('redis').createClient();
// ... Construct your application ...
app.use(ltiMiddleware({
// You must use either the credentials option or the consumer_key and
// consumer_secret. The credentials option a function that accepts a key and
// a callback to perform an asynchronous operation to fetch the secret.
credentials: function (key, callback) {
// use this function to dynamically look up a secret based on the key
// allowing you to have multiple key/secret pairs
// `this` is a reference to the express request object.
// The first parameter is an error (null if there is none).
// 2nd is the consumer key, we'll just pass the key we got back
// 3rd is the consumer secret that matches this key, used to validate the OAuth signature
callback(null, key, 'dynamic_secret_value_for_this_key');
},
consumer_key: "key", // Required if not using credentials key shown above.
consumer_secret: "secret", // Required if not using credentials key shown above.
// Optional Nonce Storage
// `store` expects an instance of a lti.stores.NonceStore object
// defaults to `new lti.stores.MemoryStore()`
// Examples:
// `store: new MyCustomNonceStore()`
// `store: new lti.stores.RedisStore('consumer_key', redisClient)`
store: new lti.stores.MemoryStore()
}));