feat: options.cache and account.ready

BREAKING CHANGE:

As part of our effort to make Hoodie Client compatible with Service Worker and other environments that do not have access to localStorage, we have to make the Account Client compatible with async store APIs. That means we can’t load the current account state synchronously, so this is no longer be possible:

```js
var account = new Account({
  url: /api
})
if (account.isSignedIn()) {
  sayHi(account.username)
}
```

Starting with this release, you have to wrap the synchronous methods and properties into `account.ready.then()`

```js
account.ready.then(function () {
  if (account.isSignedIn()) {
    sayHi(account.username)
  }
})
```

By default, the account will still use localStorage (via [humble-localstorage](https://github.com/gr2m/humble-localstorage)) to persist its state, but it will now be made asynchronous. In order to use another storage a new `options.cache` argument can be passed to the Account constructor:

```js
var account = new Account({
  url: /api,
  cache: {
    set: writeAccountState
    get: getAccountState,
    unset: clearAccountState,
  }
})
```

All three `options.cache` methods must return promises. `options.cache.get` must resolve with the persisted account properties or an empty object.

admin/index.js

@@ -2,6 +2,7 @@ module.exports = AccountAdmin
 
 var EventEmitter = require('events').EventEmitter
 var Hook = require('before-after-hook')
+var LocalStorageStore = require('async-get-set-store')
 
 var getUsername = require('../lib/username')
 var signIn = require('../lib/sign-in')
@@ -17,7 +18,6 @@ var accountsRemove = require('./lib/accounts/remove')
 var sessionsAdd = require('./lib/sessions/add')
 
 var events = require('../lib/events')
-var LocalStorageStore = require('../utils/localstorage-store')
 
 function AccountAdmin (options) {
   if (!(this instanceof AccountAdmin)) {
@@ -31,16 +31,19 @@ function AccountAdmin (options) {
   var cacheKey = options.cacheKey || 'account_admin'
   var emitter = options.emitter || new EventEmitter()
   var accountsEmitter = new EventEmitter()
-  var store = new LocalStorageStore(cacheKey)
+  var cache = options.cache || new LocalStorageStore(cacheKey)
 
   var state = {
     accountsEmitter: accountsEmitter,
     cacheKey: cacheKey,
     emitter: emitter,
-    account: store.get(),
-    store: store,
+    account: undefined,
+    cache: cache,
     url: options.url,
-    hook: new Hook()
+    hook: new Hook(),
+    ready: cache.get().then(function (storedAccount) {
+      state.account = storedAccount
+    })
   }
 
   var admin = {
@@ -73,7 +76,10 @@ function AccountAdmin (options) {
     on: events.on.bind(null, state),
     one: events.one.bind(null, state),
     off: events.off.bind(null, state),
-    hook: state.hook.api
+    hook: state.hook.api,
+    ready: state.ready.then(function () {
+      return admin
+    })
   }
 
   // sessions.add can use accounts.find to lookup user id by username

admin/lib/accounts/add.js

@@ -6,13 +6,17 @@ internals.deserialise = require('../../../utils/deserialise')
 internals.serialise = require('../../../utils/serialise')
 
 function add (state, account, options) {
-  return internals.request({
-    url: state.url + '/accounts' + query(options),
-    method: 'POST',
-    headers: {
-      authorization: 'Session ' + state.account.session.id
-    },
-    body: internals.serialise('account', account)
+  return state.ready
+
+  .then(function () {
+    return internals.request({
+      url: state.url + '/accounts' + query(options),
+      method: 'POST',
+      headers: {
+        authorization: 'Session ' + state.account.session.id
+      },
+      body: internals.serialise('account', account)
+    })
   })
 
   .then(function (response) {

admin/lib/accounts/find-all.js

@@ -5,12 +5,16 @@ internals.request = require('../../../utils/request')
 internals.deserialise = require('../../../utils/deserialise')
 
 function findAll (state, options) {
-  return internals.request({
-    method: 'GET',
-    url: state.url + '/accounts' + query(options),
-    headers: {
-      authorization: 'Session ' + state.account.session.id
-    }
+  return state.ready
+
+  .then(function () {
+    return internals.request({
+      method: 'GET',
+      url: state.url + '/accounts' + query(options),
+      headers: {
+        authorization: 'Session ' + state.account.session.id
+      }
+    })
   })
 
   .then(function (response) {

admin/lib/accounts/find.js

@@ -5,12 +5,16 @@ internals.request = require('../../../utils/request')
 internals.deserialise = require('../../../utils/deserialise')
 
 function find (state, id, options) {
-  return internals.request({
-    url: state.url + '/accounts/' + id + query(options),
-    method: 'GET',
-    headers: {
-      authorization: 'Session ' + state.account.session.id
-    }
+  return state.ready
+
+  .then(function () {
+    return internals.request({
+      url: state.url + '/accounts/' + id + query(options),
+      method: 'GET',
+      headers: {
+        authorization: 'Session ' + state.account.session.id
+      }
+    })
   })
 
   .then(function (response) {

admin/lib/accounts/remove.js

@@ -7,7 +7,11 @@ internals.find = require('./find')
 function remove (state, id, options) {
   var account
 
-  return internals.find(state, id, options)
+  return state.ready
+
+  .then(function () {
+    return internals.find(state, id, options)
+  })
 
   .then(function (_account) {
     account = _account

admin/lib/accounts/update.js

@@ -10,7 +10,11 @@ internals.serialise = require('../../../utils/serialise')
 function update (state, id, change, options) {
   var account
 
-  return internals.find(state, id, options)
+  return state.ready
+
+  .then(function () {
+    return internals.find(state, id, options)
+  })
 
   .then(function (_account) {
     account = _account

admin/lib/sessions/add.js

@@ -12,29 +12,33 @@ function add (state, options) {
     return Promise.reject(new Error('options.username is required'))
   }
 
-  // TODO: use accountsFind instead of accountsFindAll
-  //       after updating accountsFind to match admin README doc
-  // return accountsFind(state, {username: options.username})
-  return accountsFindAll(state)
-    .then(function (response) {
-      var accountInfo = _.filter(
-        response, {username: options.username})[0]
-      if (!accountInfo) {
-        var notFoundErr = new Error('account not found')
-        notFoundErr.name = 'NotFoundError'
-        throw notFoundErr
-      }
+  return state.ready
 
-      return internals.request({
-        url: state.url + '/accounts/' + accountInfo.id + '/sessions',
-        method: 'POST',
-        headers: {
-          authorization: 'Session ' + state.account.session.id
+  .then(function () {
+    // TODO: use accountsFind instead of accountsFindAll
+    //       after updating accountsFind to match admin README doc
+    // return accountsFind(state, {username: options.username})
+    return accountsFindAll(state)
+      .then(function (response) {
+        var accountInfo = _.filter(
+          response, {username: options.username})[0]
+        if (!accountInfo) {
+          var notFoundErr = new Error('account not found')
+          notFoundErr.name = 'NotFoundError'
+          throw notFoundErr
         }
+
+        return internals.request({
+          url: state.url + '/accounts/' + accountInfo.id + '/sessions',
+          method: 'POST',
+          headers: {
+            authorization: 'Session ' + state.account.session.id
+          }
+        })
+      }).then(function (response) {
+        return internals.deserialise(response.body, {
+          include: 'account'
+        })
       })
-    }).then(function (response) {
-      return internals.deserialise(response.body, {
-        include: 'account'
-      })
-    })
+  })
 }

index.js

@@ -13,7 +13,7 @@ function Account (options) {
 
   var state = getState(options)
 
-  return {
+  var api = {
     get username () {
       return getUsername(state)
     },
@@ -39,6 +39,9 @@ function Account (options) {
     one: events.one.bind(null, state),
     off: events.off.bind(null, state),
     hook: state.hook.api,
-    validate: require('./lib/validate').bind(null, state)
+    validate: require('./lib/validate').bind(null, state),
+    ready: state.ready.then(function () { return api })
   }
+
+  return api
 }

lib/destroy.js

@@ -8,24 +8,25 @@ internals.get = require('./get')
 internals.isSignedIn = require('./is-signed-in')
 
 function destroy (state) {
-  var accountProperties = internals.get(state)
+  var accountProperties
+  return state.ready
 
-  var promise = Promise.resolve()
+  .then(function () {
+    accountProperties = internals.get(state)
 
-  if (internals.isSignedIn(state)) {
-    promise = promise.then(function () {
-      internals.request({
+    if (internals.isSignedIn(state)) {
+      return internals.request({
         method: 'DELETE',
         url: state.url + '/session/account',
         headers: {
           authorization: 'Session ' + state.account.session.id
         }
       })
-    })
-  }
+    }
+  })
 
-  return promise.then(function () {
-    state.store.unset()
+  .then(function () {
+    state.cache.unset()
 
     state.emitter.emit('signout', clone(state.account))
     state.emitter.emit('destroy', clone(state.account))

lib/fetch.js

@@ -7,17 +7,23 @@ var set = require('lodash/set')
 
 var internals = module.exports.internals = {}
 internals.fetchProperties = require('../utils/fetch-properties')
+internals.fetchProperties = require('../utils/fetch-properties')
 
 function fetch (state, path) {
-  if (!state.account) {
-    var error = new Error('Not signed in')
-    error.name = 'UnauthenticatedError'
-    return Promise.reject(error)
-  }
-  return internals.fetchProperties({
-    url: state.url + '/session/account',
-    sessionId: get(state, 'account.session.id'),
-    path: path
+  return state.ready
+
+  .then(function () {
+    if (get(state, 'account.session') === undefined) {
+      var error = new Error('Not signed in')
+      error.name = 'UnauthenticatedError'
+      return Promise.reject(error)
+    }
+
+    return internals.fetchProperties({
+      url: state.url + '/session/account',
+      sessionId: get(state, 'account.session.id'),
+      path: path
+    })
   })
 
   .then(function (properties) {
@@ -27,7 +33,7 @@ function fetch (state, path) {
       merge(state.account, properties)
     }
 
-    state.store.set(state.account)
+    state.cache.set(state.account)
 
     return properties
   })
@@ -37,7 +43,7 @@ function fetch (state, path) {
       state.account.session.invalid = true
       state.emitter.emit('unauthenticate')
 
-      state.store.set(state.account)
+      state.cache.set(state.account)
     }
 
     throw error

lib/get.js

@@ -4,5 +4,9 @@ var internals = module.exports.internals = {}
 internals.getProperties = require('../utils/get-properties')
 
 function accountGet (state, path) {
+  if (!state.account) {
+    throw new Error('account.get() not yet accessible, wait for account.ready to resolve')
+  }
+
   return internals.getProperties(state.account, path)
 }

lib/has-invalid-session.js

@@ -3,5 +3,9 @@ module.exports = hasInvalidSession
 var get = require('lodash/get')
 
 function hasInvalidSession (state) {
+  if (!state.account) {
+    throw new Error('account.hasInvalidSession() not yet accessible, wait for account.ready to resolve')
+  }
+
   return get(state, 'account.session.invalid')
 }

lib/id.js

@@ -1,13 +1,8 @@
 module.exports = getId
 
-var generateId = require('../utils/generate-id')
-
 function getId (state) {
   if (!state.account) {
-    state.account = {
-      id: generateId()
-    }
-    state.store.set(state.account)
+    throw new Error('account.id not yet accessible, wait for account.ready to resolve')
   }
   return state.account.id
 }

lib/is-signed-in.js

@@ -3,5 +3,9 @@ module.exports = isSignedIn
 var get = require('lodash/get')
 
 function isSignedIn (state) {
+  if (!state.account) {
+    throw new Error('account.isSignedIn() not yet accessible, wait for account.ready to resolve')
+  }
+
   return get(state, 'account.session') !== undefined
 }

lib/profile-fetch.js

@@ -7,10 +7,14 @@ var internals = module.exports.internals = {}
 internals.fetchProperties = require('../utils/fetch-properties')
 
 function profileFetch (state, path) {
-  return internals.fetchProperties({
-    url: state.url + '/session/account/profile',
-    sessionId: get(state, 'account.session.id'),
-    path: path
+  return state.ready
+
+  .then(function () {
+    return internals.fetchProperties({
+      url: state.url + '/session/account/profile',
+      sessionId: get(state, 'account.session.id'),
+      path: path
+    })
   })
 
   .then(function (properties) {
@@ -20,7 +24,7 @@ function profileFetch (state, path) {
       set(state.account, 'profile', properties)
     }
 
-    state.store.set(state.account)
+    state.cache.set(state.account)
 
     return properties
   })
@@ -30,7 +34,7 @@ function profileFetch (state, path) {
       state.account.session.invalid = true
       state.emitter.emit('unauthenticate')
 
-      state.store.set(state.account)
+      state.cache.set(state.account)
     }
 
     throw error