blockstack-storage/lib/metadata.js

The Blockstack Javascript library for storage.

'use strict';

Object.defineProperty(exports, "__esModule", {
   value: true
});
exports.getUserData = getUserData;
exports.getGaiaLocalData = getGaiaLocalData;
exports.setUserData = setUserData;
exports.setGaiaLocalData = setGaiaLocalData;
exports.getCachedMountContext = getCachedMountContext;
exports.setCachedMountContext = setCachedMountContext;
exports.deleteCachedMountContext = deleteCachedMountContext;
exports.getBlockchainIDFromSessionOrDefault = getBlockchainIDFromSessionOrDefault;
exports.getSessionToken = getSessionToken;
exports.getSessionBlockchainID = getSessionBlockchainID;
exports.getSessionDatastoreID = getSessionDatastoreID;
exports.getSessionAppName = getSessionAppName;
exports.getSessionDeviceID = getSessionDeviceID;
exports.getDeviceRootVersion = getDeviceRootVersion;
exports.putDeviceRootVersion = putDeviceRootVersion;

var _util = require('./util');

var LOCAL_STORAGE_ID = 'blockstack';
var LOCAL_STORAGE_GAIA_ID = 'blockstack-gaia';

var urlparse = require('url');
var crypto = require('crypto');
var jsontokens = require('jsontokens');
var assert = require('assert');

/*
 * Get a reference to our localStorage implementation
 */
function getLocalStorage() {
   return localStorage;
}

/*
 * Get local storage object for Blockstack
 * Throws on error
 */
function getUserData() {

   var localStorage = getLocalStorage();
   var userData = localStorage.getItem(LOCAL_STORAGE_ID);
   if (userData === null || typeof userData === 'undefined') {
      userData = '{}';
   }

   userData = JSON.parse(userData);
   return userData;
}

/*
 * Get Gaia-specific local data
 * Throws on error
 */
function getGaiaLocalData() {

   var localStorage = getLocalStorage();
   var userData = localStorage.getItem(LOCAL_STORAGE_GAIA_ID);
   if (userData === null || typeof userData === 'undefined') {
      userData = '{}';
   }

   userData = JSON.parse(userData);
   return userData;
}

/*
 * Save local storage
 */
function setUserData(userData) {

   var u = getUserData();
   if (u.coreSessionToken && userData.coreSessionToken) {
      // only store the newer one 
      var coreSessionToken = null;
      if (u.coreSessionToken.timestamp < userData.coreSessionToken.timestamp) {
         coreSessionToken = userData.coreSessionToken;
      } else {
         coreSessionToken = u.coreSessionToken;
      }
      userData.coreSessionToken = coreSessionToken;
   }

   localStorage.setItem(LOCAL_STORAGE_ID, JSON.stringify(userData));
}

/*
 * Save local Gaia state
 */
function setGaiaLocalData(userData) {
   localStorage.setItem(LOCAL_STORAGE_GAIA_ID, JSON.stringify(userData));
}

/*
 * Get a cached app-specific datastore mount context for a given blockchain ID and application
 * Return null if not found
 * Throws on error
 */
function getCachedMountContext(blockchain_or_datastore_id, full_app_name) {

   var userData = getUserData();
   assert(userData);

   assert(blockchain_or_datastore_id, 'No blockchain ID given');
   assert(full_app_name, 'No app name given');

   var cache_key = blockchain_or_datastore_id + '/' + full_app_name;

   if (!userData.datastore_contexts) {
      console.log("No datastore contexts defined");
      return null;
   }

   if (!userData.datastore_contexts[cache_key]) {
      console.log('No datastore contexts for ' + blockchain_or_datastore_id + ' in ' + full_app_name);
      return null;
   }

   var ctx = userData.datastore_contexts[cache_key];
   if (!ctx) {
      console.log('Null datastore context for ' + blockchain_or_datastore_id + ' in ' + full_app_name);
      return null;
   }

   return ctx;
}

/*
 * Cache a mount context for a blockchain ID
 *
 * @param blockchain_or_datastore_id (string) the blockchain ID or datastore ID
 * @param full_app_name (string) the fully-qualified application name
 * @param datastore_context (object) the datastore mount context
 */
function setCachedMountContext(blockchain_or_datastore_id, full_app_name, datastore_context) {

   var userData = getUserData();
   assert(userData);

   assert(blockchain_or_datastore_id, 'No blockchain ID given');
   assert(full_app_name, 'No app name given');

   if (!userData.datastore_contexts) {
      userData.datastore_contexts = {};
   }

   var cache_key = blockchain_or_datastore_id + '/' + full_app_name;
   userData.datastore_contexts[cache_key] = datastore_context;
   setUserData(userData);
}

/*
 * Uncache a mount context for a blockchain ID
 *
 * @param blockchain_or_datastore_id (string) the blockchain ID or datastore ID
 * @param full_app_name (string) the fully-qualified application name
 */
function deleteCachedMountContext(blockchain_or_datastore_id, full_app_name) {

   var userData = getUserData();
   assert(userData);

   assert(blockchain_or_datastore_id, 'No blockchain ID given');
   assert(full_app_name, 'No app name given');

   if (!userData.datastore_contexts) {
      return true;
   }

   var cache_key = blockchain_or_datastore_id + '/' + full_app_name;
   if (!Objects.keys(userData.datastore_contexts).includes(cache_key)) {
      return true;
   }

   delete userData.datastore_contexts[cache_key];
   setUserData(userData);
}

/*
 * Get the blockchain ID from a session object, or generate a default one
 * if no blockchain ID is set.
 *
 * @param session (object) the parsed session object
 *
 * Returns a string that is either the blockchain ID, or a deterministically-generated base64-encoded string
 * that is consistent for the datastore
 */
function getBlockchainIDFromSessionOrDefault(session) {
   if (!session.blockchain_id) {
      assert(session.app_user_id, 'Missing app_user_id in ' + JSON.stringify(session));
      return (0, _util.hashRawData)(Buffer.from(session.app_user_id).toString('base64'));
   } else {
      return session.blockchain_id;
   }
}

/*
 * Get the session token from localstorage
 */
function getSessionToken() {
   var userData = getUserData();
   assert(userData);
   assert(userData.coreSessionToken);

   var sessionToken = userData.coreSessionToken;
   return sessionToken;
}

/*
 * Get the current session's blockchain ID
 */
function getSessionBlockchainID() {
   var sessionToken = arguments.length > 0 && arguments[0] !== undefined ? arguments[0] : null;


   if (!sessionToken) {
      sessionToken = getSessionToken();
   }

   var session = jsontokens.decodeToken(sessionToken).payload;
   return session.blockchain_id;
}

/*
 * Get the current session's datastore ID 
 */
function getSessionDatastoreID() {
   var sessionToken = arguments.length > 0 && arguments[0] !== undefined ? arguments[0] : null;


   if (!sessionToken) {
      sessionToken = getSessionToken();
   }

   var session = jsontokens.decodeToken(sessionToken).payload;
   return session.app_user_id;
}

/*
 * Get the fully-qualified application name from the session
 */
function getSessionAppName() {
   var sessionToken = arguments.length > 0 && arguments[0] !== undefined ? arguments[0] : null;


   if (!sessionToken) {
      sessionToken = getSessionToken();
   }

   var session = jsontokens.decodeToken(sessionToken).payload;
   assert(session.app_domain, 'Missing app_domain in session ' + sessionToken);

   var domainName = session.app_domain;
   var urlInfo = urlparse.parse(domainName);
   if (!urlInfo.slashes) {
      domainName = 'http://' + domainName;
   }

   var appname = urlparse.parse(domainName).host;
   assert(appname, 'Unparseable app_domain in session ' + sessionToken);
   return appname;
}

/*
 * Get the session's device ID
 */
function getSessionDeviceID() {
   var sessionToken = arguments.length > 0 && arguments[0] !== undefined ? arguments[0] : null;


   if (!sessionToken) {
      sessionToken = getSessionToken();
   }

   var session = jsontokens.decodeToken(sessionToken).payload;
   return session.device_id;
}

/*
 * Get the version of a device root page
 *
 * @param datastore_id (string) the datastore ID
 * @param root_uuid (string) the root UUID
 * @param device_ids (array) the list of device IDs
 *
 * Returns the version (integer) on success
 * Returns 0 if we don't know
 */
function getDeviceRootVersion(datastore_id, root_uuid, device_ids) {
   // TODO 
   return 0;
}

/*
 * Put the version of a device root page
 *
 * @param datastore_id (string) the datastore ID
 * @param root_uuid (string) the root UUID
 * @param device_id (string) this device ID
 * @version (integer) the version number
 *
 * returns True
 */
function putDeviceRootVersion(datastore_id, root_uuid, device_id, version) {
   // TODO 
   return true;
}