@cerebral/firebase

install

NPM

npm install @cerebral/firebase

description

The Firebase provider is a Cerebral friendly wrapper around the Firebase client. By default the Firebase client is heavily event based, even just getting some value, handling authentication etc. This is useful in some types of apps, but Cerebral has a very straight forward way of thinking about side effects. You will find that a lot of the API exposed by the Firebase client is simplified!

instantiate

import {Controller} from 'cerebral'
import FirebaseProvider from '@cerebral/firebase'

const controller = Controller({
  providers: [
    FirebaseProvider({
      config: {
        apiKey: '{apiKey}',
        authDomain: '{authDomain}',
        databaseURL: '{databaseURL}',
        storageBucket: '{storageBucket}'
      },
      // When using tasks and firebase queue you can prefix
      // the specs triggered. This is useful in development
      // when multiple developers are working on the
      // same instance
      specPrefix: 'CJ'
    })
  ]
})

Important notes

  • The Cerebral firebase provider uses dot notation to keep consistency with Cerebral itself

  • All factories supports template tags, allowing you to dynamically create paths and points to values

error

FirebaseProviderError (base)

import {FirebaseProviderError} from '@cerebral/firebase'

// Error structure
{
  name: 'HttpProviderError',
  message: 'Some firebase error message'
  stack: '...'  
}

FirebaseProviderAuthenticationError

import {FirebaseProviderAuthenticationError} from '@cerebral/firebase'

// Error structure
{
  name: 'HttpProviderError',
  message: 'Some firebase error message'
  code: 10 // firebase auth error code
  stack: '...'  
}

set

Write data to this database location. This will overwrite any data at this location and all child locations. Passing null for the new value is equivalent to calling remove(); all data at this location or any child location will be deleted.

action

function someAction({firebase}) {
  return firebase.set('foo.bar', 'baz')
}

factory

import {props} from 'cerebral/tags'
import {set} from '@cerebral/firebase/operators'

export default [
  set('foo.bar', props`foo`),

  // Alternatively with explicit paths
  set('foo.bar', props`foo`), {
    success: [],
    error: []
  }
]

output No output

update

As opposed to the set() method, update() can be use to selectively update only the referenced properties at the current location (instead of replacing all the child properties at the current location).

action

function someAction({firebase}) {
  return firebase.update('some.path', {
    'foo': 'bar',
    'items.item1.isAwesome': true
  })
}

factory

import {props} from 'cerebral/tags'
import {update} from '@cerebral/firebase/operators'

export default [
  update('some.path', {
    'foo.bar': props`bar`,
    'foo.baz': props`baz`
  }),

  // Alternatively with explicit paths
  update('some.path', {
    'foo.bar': props`bar`,
    'foo.baz': props`baz`
  }), {
    success: [],
    error: []
  }
]

output No output

push

Generates a new child location using a unique key and returns its reference from the action. An example being {key: "-KWKImT_t3SLmkJ4s3-w"}.

action

function someAction({firebase}) {
  return firebase.push('users', {
    name: 'Bob'
  })
}

factory

import {state} from 'cerebral/tags'
import {push} from '@cerebral/firebase/operators'

export default [
  push('users', state`newUser`),

  // Alternatively with explicit paths
  push('users', state`newUser`), {
    success: [],
    error: []
  }
]

output

{key: 'theAddedKey'}

remove

Remove the data at this database location.

action

function someAction({ firebase}) {
  return firebase.remove('foo.bar')
}

factory

import {props, string} from 'cerebral/tags'
import {remove} from '@cerebral/firebase/operators'

export default [
  remove(string`users.${props`userKey`}`),

  // Alternatively with explicit paths
  remove(string`users.${props`userKey`}`), {
    success: [],
    error: []
  }
]

output No output

transaction

Atomically modifies the data at the provided location.

Unlike a normal set(), which just overwrites the data regardless of its previous value, transaction() is used to modify the existing value to a new value, ensuring there are no conflicts with other clients writing to the same location at the same time.

To accomplish this, you pass transaction() an update function which is used to transform the current value into a new value. If another client writes to the location before your new value is successfully written, your update function will be called again with the new current value, and the write will be retried. This will happen repeatedly until your write succeeds without conflict or you abort the transaction by not returning a value from your update function.

action

function someAction({firebase}) {

  function transactionFunction(currentData){
    if (currentData === null) {
      return { foo: 'bar' }
    }

    return // Abort the transaction.
  }

  return firebase.transaction('some.transaction.path', transactionFunction)
    .then((result) => {
      if(result.committed){
        return {result: result.value}
      } else {
        throw new Error('Transaction failed')
      }
    })
}

factory

import {transaction} from '@cerebral/firebase/operators'

function transactionFunction(currentData){
  if (currentData === null) {
    return { foo: 'bar' }
  }

  return // Abort the transaction.
}

export default [
  transaction('foo.bar', transactionFunction),

  // Alternatively with explicit paths
  transaction('foo.bar', transactionFunction), {
    success: [],
    error: []
  }
]

output

{committed: true, value: 'new value'}

Note: Modifying data with set() will cancel any pending transactions at that location, so extreme care should be taken if mixing set() and transaction() to update the same data.

Note: When using transactions with Security and Firebase Rules in place, be aware that a client needs .read access in addition to .write access in order to perform a transaction. This is because the client-side nature of transactions requires the client to read the data in order to transactionally update it.

value

action

function someAction({ firebase }) {
  return firebase.value('someKey.foo', {
    limitToFirst: 5, // Read Firebase docs
    limitToLast: 5, // Read Firebase docs
    startAt: 5, // Read Firebase docs
    endAt: 5, // Read Firebase docs
    equalTo: 5, // Read Firebase docs
    orderByChild: 'count', // Read Firebase docs
    orderByKey: true, // Read Firebase docs
    orderByValue: true, // Read Firebase docs

    // Set to true to get an array of {key: '', value: {}}
    // Useful with ordering options
    asArray: false,
  })
}

factory

import {value} from '@cerebral/firebase/operators'
import {state} from 'cerebral/tags'

export default [
  value('foo.bar', {
    asArray: true,
    orderByChild: state`currentOrderChild`
  }),

  // Alternatively with explicit paths
  value('foo.bar'), {
    success: [],
    error: []
  }
]

output

// Normally
{key: 'keyYouLookedUpValueOn', value: 'the value'}

// With "asArray"
[{key: 'keyYouLookedUpValueOn', value: 'the value'}, {key: 'keyYouLookedUpValueOn', value: 'the value'}]

onValue

action

function someAction({ firebase }) {
  firebase.onValue('someKey.foo', 'someModule.fooUpdated',  {
    payload: {}, // Merged with the payload passed on new data
  });
}

This will NOT immediately grab the value and trigger the signal passed, the first event is discarded for more predictable behaviour. To grab existing value, just use value.

To stop listening for updates to the value:

function someAction({ firebase }) {
  firebase.off('someKey.foo', 'onValue');
}

factory

import {onValue} from '@cerebral/firebase/operators'

export default [
  onValue('foo.bar', 'some.signal')
]

onChildAdded

action

function someAction({ firebase }) {
  firebase.onChildAdded('posts', 'posts.postAdded', {
    payload: {}, // Merged with the payload passed on new data
    limitToFirst: 5, // Read Firebase docs
    limitToLast: 5, // Read Firebase docs
    startAt: 5, // Read Firebase docs
    endAt: 5, // Read Firebase docs
    equalTo: 5, // Read Firebase docs
    orderByChild: 'count', // Read Firebase docs
    orderByKey: true, // Read Firebase docs
    orderByValue: true // Read Firebase docs
  });
}

This will immediately grab and trigger the signal posts.postAdded for every post grabbed. Note this is just registering a listener, not returning a value from the action. The signal is triggered with the payload: { key: 'someKey', value: {} }.

To stop listening for updates to the posts:

function someAction({ firebase }) {
  firebase.off('posts', 'onChildAdded');
}

factory

import {state} from 'cerebral/tags'
import {onChildAdded} from '@cerebral/firebase/operators'

export default [
  onChildAdded('foo.bar', 'some.signal', {
    orderByChild: 'count',
    limitToFirst: state`config.limitToFirst`
  })
]

onChildRemoved

action

function someAction({ firebase }) {
  firebase.onChildRemoved('posts', 'posts.postRemoved', {
    // Same options as above
  });
}

This will trigger the signal posts.postRemoved whenever a post is removed from the selection. The signal is triggered with the payload: { key: 'someKey' }.

To stop listening:

function someAction({ firebase }) {
  firebase.off('posts', 'onChildRemoved');
}

factory

import {onChildRemoved} from '@cerebral/firebase/operators'

export default [
  onChildRemoved('foo.bar', 'some.signal', {
    // Same options as above
  })
]

onChildChanged

action

function someAction({ firebase }) {
  firebase.onChildChanged('posts', 'posts.postChanged', {
    // Same options as above
  });
}

This will trigger the signal posts.postChanged whenever a post is changed in the selection. The signal is triggered with the payload: { key: 'someKey', value: {} }.

To stop listening:

function someAction({ firebase }) {
  firebase.off('posts', 'onChildChanged');
}

factory

import {onChildChanged} from '@cerebral/firebase/operators'

export default [
  onChildChanged('foo.bar', 'some.signal', {
    // Same options as above
  })
]

off

action

function someAction({ firebase }) {
  // Turn off listener at specific path and
  // specific event
  firebase.off('posts', 'onChildChanged')

  // Turn off all listeners at specific path
  firebase.off('posts', 'onChildChanged')

  // Turn off all listeners of specific event at wildcard path
  firebase.off('posts.*', 'onChildChanged')

  // Turn off all listeners at wildcard path
  firebase.off('posts.*')
}

factory

import {string} from 'cerebral/tags'
import {off} from '@cerebral/firebase/operators'

export default [
  // Same API as in actions, also wildcard
  off('posts', 'onChildChanged'),

  // Compose using string tag
  off(string`posts.${state`selectedPostKey`}`)
]

task

If you are using the firebase-queue and need to create tasks, you can do that with:

action

function someAction({ firebase, state }) {
  return firebase.task('create_post', {
    uid: state.get('app.user.uid'),
    text: state.get('posts.newPostText')
  })
}

This will add a task at queue/tasks. There is no output from a resolved task, it just resolves when the action has been processed.

factory

import {state, props} from 'cerebral/tags'
import {task} from '@cerebral/firebase/operators'

export default [
  task('some_task', {
    uid: state`user.uid`,
    data: props`data`
  }),

  // Alternatively with explicit paths
  task('some_task', {
    uid: state`user.uid`,
    data: props`data`
  }), {
    success: [],
    error: []
  }
]

output No output

getUser

Will resolve to {user: {}} if user exists. If user was redirected from Facebook/Google etc. as part of first sign in, this method will handle the confirmed registration of the user.

action

function someAction({ firebase }) {
  return firebase.getUser()
}

factory

import {getUser} from '@cerebral/firebase/operators'

export default [
  getUser(),

  // Alternatively with explicit paths
  getUser(), {
    success: [],
    error: []
  }
]

output

{user: {}}

signInAnonymously

This login will method will resolve to existing anonymous or create a new one for you.

action

function someAction({ firebase }) {
  return firebase.signInAnonymously()
}

factory

import {signInAnonymously} from '@cerebral/firebase/operators'

export default [
  signInAnonymously(),

  // Alternatively with explicit paths
  signInAnonymously(), {
    success: [],
    error: []
  }
]

output

{user: {}}

createUserWithEmailAndPassword

Register a new user with email and password.

action

function someAction({ firebase, state }) {
  const email = state.get('register.email')
  const password = state.get('register.password')

  return firebase.createUserWithEmailAndPassword(email, password)
}

factory

import {state} from 'cerebral/tags'
import {createUserWithEmailAndPassword} from '@cerebral/firebase/operators'

export default [
  createUserWithEmailAndPassword(state`newUser.email`, state`newUser.password`),

  // Alternatively with explicit paths
  createUserWithEmailAndPassword(state`newUser.email`, state`newUser.password`), {
    success: [],
    error: []
  }
]

output

{user: {}}

signInWithEmailAndPassword

Sign in a user with email and password.

action

function someAction({ firebase, state }) {
  const email = state.get('register.email')
  const password = state.get('register.password')

  return firebase.signInWithEmailAndPassword(email, password)
}

factory

import {props} from 'cerebral/tags'
import {signInWithEmailAndPassword} from '@cerebral/firebase/operators'

export default [
  signInWithEmailAndPassword(props`email`, props`password`),

  // Alternatively with explicit paths
  signInWithEmailAndPassword(props`email`, props`password`), {
    success: [],
    error: []
  }
]

output

{user: {}}

signInWith{PROVIDER}

Sign in a user with Facebook, Google or Github.

action

function someAction({ firebase, state }) {
  return firebase.signInWithFacebook({
    redirect: false, // Use popup or redirect. Redirect typically for mobile
    scopes: [] // Facebook scopes to access
  })
}

factory

import {state} from 'cerebral/tags'
import {signInWithFacebook} from '@cerebral/firebase/operators'

export default [
  signInWithFacebook({
    redirect: state`useragent.media.small`
  }),

  // Alternatively with explicit paths
  signInWithFacebook({
    redirect: state`useragent.media.small`
  }), {
    success: [],
    error: []
  }
]

output Either this will be a redirect or it outputs:

{user: {}}

Similar you can sign in with Google or GitHub. Just use signInWithGoogle or signInWithGithub instead of signInWithFacebook.

signInWithCustomToken

Sign in a custom token.

action

function someAction({ firebase, state }) {
  return firebase.signInWithCustomToken(state.get('token'))
}

factory

import {props, state} from 'cerebral/tags'
import {signInWithCustomToken} from '@cerebral/firebase/operators'

export default [
  signInWithCustomToken(props`token`),

  // Alternatively with explicit paths
  signInWithCustomToken(state`token`), {
    success: [],
    error: []
  }
]

output

{user: {}}

linkWithFacebook{PROVIDER}

Link an anonymous account with Facebook, Google or Github.

action

function someAction({ firebase, state }) {
  return firebase.linkWithFacebook({
    redirect: false, // Use popup or redirect. Redirect typically for mobile
    scopes: [] // Facebook scopes to access
  })
}

factory

import {state} from 'cerebral/tags'
import {linkWithFacebook} from '@cerebral/firebase/operators'

export default [
  linkWithFacebook({
    redirect: state`useragent.media.small`
  }),

  // Alternatively with explicit paths
  linkWithFacebook({
    redirect: state`useragent.media.small`
  }), {
    success: [],
    error: []
  }
]

output Either this will be a redirect or it outputs:

{user: {}}

Similar you can sign in with Google or GitHub. Just use linkWithGoogle or linkWithGithub instead of linkWithFacebook.

signOut

Sign out user. getUser will now not resolve a user anymore.

action

function someAction({ firebase }) {
  return firebase.signOut()
}

factory

import {signOut} from '@cerebral/firebase/operators'

export default [
  signOut(),

  // Alternatively with explicit paths
  signOut(), {
    success: [],
    error: []
  }
]

output No output

sendPasswordResetEmail

action

function someAction({ firebase, state }) {
  return firebase.sendPasswordResetEmail(state.get('user.email'))
}

factory

import {state} from 'cerebral/tags'
import {sendPasswordResetEmail} from '@cerebral/firebase/operators'

export default [
  sendPasswordResetEmail(state`user.email`),

  // Alternatively with explicit paths
  sendPasswordResetEmail(state`user.email`), {
    success: [],
    error: []
  }
]

output No output

setOnDisconnect

Sets a value when Firebase detects user has disconnected.

action

function someAction({ firebase, state }) {
  firebase.setOnDisconnect(`activeUsers.${state.get('app.user.uid')}`, 'someValue')
}

factory

import {state} from 'cerebral/tags'
import {setOnDisconnect} from '@cerebral/firebase/operators'

export default [
  setOnDisconnect(string`activeUsers.${state`app.user.uid`}`, null)
]

output No output

cancelOnDisconnect

Cancel setting a value when Firebase detects disconnect.

action

function someAction({ firebase, state }) {
  firebase.cancelOnDisconnect()
}

factory

import {state} from 'cerebral/tags'
import {cancelOnDisconnect} from '@cerebral/firebase/operators'

export default [
  cancelOnDisconnect()
]

output No output

put

Upload a new file at the given location. Please note that the file is not stored inside the realtime database but into Google Cloud Storage (please consult filrebase documentation). This means that you need to take care of storage security as well.

Note that put expects a folder as first argument and will use the name of the provided file. If you want to control the filename, add this in the options. In this case, make sure to respect file type and extension…

action

function someAction({ firebase, props }) {
  return firebase.put('folderName', props.file, {
    progress({progress, bytesTransferred, totalBytes, state}) {
      /* do whatever */
    },
    // Override name, make sure you set same extension
    filename: 'customName.png'
  })
}

factory

import {props, signal, string, state} from 'cerebral/tags'
import {put} from '@cerebral/firebase/operators'

// we expect props.file to contain a file provided by
// a user in an <input type='file' />
export default [
  put(string`posts.all.${props`postId`}`, props`file`, {
    // Trigger a signal which receives payload
    progress: signal`gallery.progress`
    // Set progress on a state value
    progress: state`gallery.progress`
  }),

  // Alternatively with explicit paths
  put(string`posts.all.${props`postId`}`, props`file`, {
    progress: signal`gallery.progress`
    progress: state`gallery.progress`
  }), {
    success: [],
    error: []
  }
]

output

{url: 'urlToFile', filename: 'nameOfFile'}

delete

Use delete to remove an uploaded file. Specify the containing folder and filename.

action

function someAction({ firebase, props }) {
  return firebase.delete('folderName', props.fileName)
}

factory

import {props, state, string} from 'cerebral/tags'
import {delete as firebaseDelete} from '@cerebral/firebase/operators'

export default [
  firebaseDelete(
    string`posts.all.${props`postId`}`,
    state`posts.all.${props`postId`}.imageName`
  ),

  // Alternatively with explicit paths
  firebaseDelete(
    string`posts.all.${props`postId`}`,
    state`posts.all.${props`postId`}.imageName`
  ), {
    success: [],
    error: []
  }
]

output No output