JavaScript driver for Fauna v4 (deprecated)

> [!WARNING] > Fauna is decommissioning FQL v4 on June 30, 2025. > > This driver is not compatible with FQL v10, the latest version. Fauna accounts > created after August 21, 2024 must use FQL v10. Ensure you migrate existing > projects to the official v10 driver by the v4 EOL date: > https://github.com/fauna/fauna-js. > > For more information, see the v4 end of life (EOL) > announcement and > related FAQ.

The official JavaScript driver for Fauna v4.

View reference JSDocs here.

See the FaunaDB Documentation and Tutorials for guides and a complete database API reference.

Supported Runtimes

This Driver supports and is tested on:

• Node.js Current, Active LTS, and Maintenance LTS releases
  • Current - v17
  • Active LTS - currently v16
  • Maintenance LTS - v12 and v14
• Chrome
• Firefox
• Safari
• Internet Explorer 11

Using the Client

Installation

Node.js

npm install --save faunadb

or

yarn add faunadb

Browsers

Via CDN:

The minified version of the driver can also be used via CDN:

Use

The tutorials in the FaunaDB documentation contain other driver-specific examples.

Connecting from the browser

To get up and running quickly, below is a full example for connecting from the browser. Replace with a database secret. You can get that by visiting your FaunaDB Dashboard, creating a new database, clicking on "Security" in the sidebar on the left, and then clicking "New Key". To learn more about keys, see FaunaDB Key System.

  
  

  <h1>Test</h1>

Requiring the Driver

var faunadb = require('faunadb'),
  q = faunadb.query

This is the recommended require stanza. The faunadb.query module contains all of the functions to create FaunaDB Query expressions.

Instantiating a Client and Issuing Queries

var client = new faunadb.Client({ secret: 'YOUR_FAUNADB_SECRET' })

Once the client has been instantiated, it can be used to issue queries. For example, to create an document in an existing collection named test with the data: { testField: 'testValue' }:

var createP = client.query(
  q.Create(q.Collection('test'), { data: { testField: 'testValue' } })
)

All methods on faunadb.Client return ES6 Promises. So, if we wanted to handle the Promise to access the Ref of the newly created document:

createP.then(function(response) {
  console.log(response.ref) // Would log the ref to console.
})

response is a JSON object containing the FaunaDB response. See the JSDocs for faunadb.Client.

The metrics option is used during instantiation to create a client that also returns usage information about the queries issued to FaunaDB.

let client = new faunadb.Client({
  secret: 'YOUR_FAUNADB_SECRET',
  metrics: true
})

Querying and Returning the metrics of your queries

The response object is shaped differently for clients when calling queryWithMetrics; it includes the value of the response along with a metrics field giving data on ops, time, and transaction retires consumed by your query:

{
  value: { ... }, // structured response body
  metrics: {
    x-compute-ops: XX,
    x-byte-read-ops: XX,
    x-byte-write-ops: XX,
    x-query-time: XX,
    x-txn-retries: XX
  } // usage data
}

Metrics returned in the response will be of number data type.

Pagination Helpers

This driver contains helpers to provide a simpler API for consuming paged responses from FaunaDB. See the Paginate function reference for a description of paged responses.

Using the helper to page over sets lets the driver handle cursoring and pagination state. For example, client.paginate:

var helper = client.paginate(q.Match(q.Index('test_index'), 'example-term'))

The return value, helper, is an instance of PageHelper. The each method will execute a callback function on each consumed page.

helper.each(function(page) {
  console.log(page) // Will log the page's contents, for example: [ Ref("collections/test/1234"), ... ]
})

Note that each returns a Promise that is fulfilled on the completion of pagination.

The pagination can be transformed server-side via the FaunaDB query language via the map and filter functions.

For example, to retrieve the matched documents:

helper
  .map(function(ref) {
    return q.Get(ref)
  })
  .each(function(page) {
    console.log(page) // Will now log the retrieved documents.
  })

See the JSDocs for more information on the pagination helper.

Timeouts

The client can be configured to handle timeouts in two different ways:

1. Add a timeout field to the options block when instantiating the client
2. By setting a queryTimeout on the client (or passing the value to the client's .query() method directly)

The first option (i.e. timeout) represents a HTTP timeout on the client side. Defined in seconds, the client will wait the specified period before timing out if it has yet to receive a response.

const client = new faunadb.Client({
  secret: 'YOUR_FAUNADB_SECRET',
  timeout: 100,
})

On the other hand, using the client's queryTimeout dictates how long FaunaDB will process the request on the server before timing out if it hasn't finished running the operation. This can be done in two different ways:

// 1. Setting the value when instantiating a new client
const client = new faunadb.Client({
  queryTimeout: 2000,
  secret: 'YOUR_FAUNADB_SECRET',
})

// 2. Specifying the value per-query
var data = client.query(q.Paginate(q.Collections()), {
  queryTimeout: 100,
})

Note: When passing a queryTimeout value to client.query() as part of the options object, it will take precendence over any value set on the client when instantiating it.

Per-query options

Some options can be provided on a per-query basis:

secret

var createP = client.query(
  q.Create(q.Collection('test'), { data: { testField: 'testValue' } }),
  { secret: 'YOUR_FAUNADB_SECRET' }
)

var helper = client.paginate(
  q.Match(q.Index('test_index'), 'example-term'),
  null,
  {
    secret: 'YOUR_FAUNADB_SECRET',
  }
)

queryTimeout

var data = client.query(q.Paginate(q.Collections()), {
  queryTimeout: 100,
})

traceparent

A W3C-compliant identifier for enabling distributed tracing across different vendors. If not provided, one is automatically generated server-side and attached to the query. Customer's should inspect the returned traceresponse to determine if a new traceparent has been created, and use that instead. See Trace Context spec for more details.

var data = client.query(q.Paginate(q.Collections()), {
  traceparent: "00-c91308c112be8448dd34dc6191567fa0-b7ad6b7169203331-01",
})

tags

Allows for associating user-provided tags with a query.

var data = client.query(q.Paginate(q.Collections()), {
  tags: { key1: "value1", key2: "value2" },
})

Both tags and their associated values, must be strings. The only allowable characters are alphanumeric values as well as an underscope (_). Max length for keys is 40 characters. Max length for values is 60 characters.

Custom Fetch

To use a custom fetch() you just have to specify it in the configuration and make it compatible with the standard Web API Specification of the Fetch API.

const customFetch = require('./customFetch')
const client = new faunadb.Client({
  secret: 'YOUR_FAUNADB_SECRET',
  fetch: customFetch,
})

HTTP/2 Session Idle Time (Node.js only)

When running on the Node.js platform, the Fauna client uses HTTP/2 multiplexing to reuse the same session for many simultaneous requests. After all open requests have been resolved, the client will keep the session open for a period of time (500ms by default) to be reused for any new requests.

The http2SessionIdleTime parameter may be used to control how long the HTTP/2 session remains open while the query connection is idle. To save on the overhead of closing and re-opening the session, set http2SessionIdleTime to a longer time. The default value is 500ms and the maximum value is 5000ms.

Note that http2SessionIdleTime has no effect on a stream connection: a stream is a long-lived connection that is intended to be held open indefinitely.

While an HTTP/2 session is alive, the client holds the Node.js event loop open; this prevents the process from terminating. Call Client#close to manually close the session and allow the process to terminate. This is particularly important if http2SessionIdleTime is long:

// sample.js (run it with "node sample.js" command)
const { Client, query: Q } = require('faunadb')

async function main() {
  const client = new Client({
    secret: 'YOUR_FAUNADB_SECRET',
    http2SessionIdleTime: 1000, // Must be a non-negative integer
  })
  const output = await client.query(Q.Add(1, 1))

  console.log(output)

  client.close()
}

main().catch(console.error)

Known issues

Using with Cloudflare Workers

Cloudflare Workers have neither XMLHttpRequest nor fetch in the global scope. Therefore, the cross-fetch package is unable to inject its own fetch() function, and throws an error. The fetch() function is injected via a closure, so the workaround would be to pass the fetch objects when initiating the FaunaDB client config. Cloudflare Workers also doesn't support the use of an AbortController, which terminates requests as well as streams. Here is a workaround:

const c = new faunadb.Client({
  secret: 'your secret',
  fetch: (url, params) => {
    const signal = params.signal
    delete params.signal
    const abortPromise = new Promise(resolve => {
      if (signal) {
        signal.onabort = resolve
      }
    })
    return Promise.race([abortPromise, fetch(url, params)])
  },
})

Client Development

Run yarn to install dependencies.

Code

This project includes no polyfills. Support for Internet Explorer 11 requires a Promise polyfill.

Testing

The driver tests need to connect to a FaunaDB so we recommend you setup one locally. The fast way is running a docker image like docker run --rm --name faunadb -p 8443:8443 fauna/faunadb.

After have the faunadb working on local you have to setup a set of env variables before run the tests. You can set them manually or use a .env file for this.

FAUNA_DOMAIN=localhost
FAUNA_SCHEME=http
FAUNA_PORT=8443
FAUNA_ROOT_KEY=secret
AUTH_0_URI=https://{TENANT}.auth0.com/
AUTH_0_TOKEN=auth0 token

Guide for Auth0

• yarn test: This will run tests against the current version of Node.js. nvm is useful for managing multiple versions of Node.js for testing.

Each test run will create a new database, and will attempt to clean it up when done. If the tests are cancelled, the test database will not get cleaned up. Therefore it is recommended to use a FaunaDB key scoped to an empty parent database created for this purpose, rather than your account's root key. This will make cleanup of test databases as easy as removing the parent database.

See the FaunaDB Multi-tenancy Tutorial for more information about nested databases.

Alternatively, tests can be run via a Docker container with FAUNA_ROOT_KEY="your-cloud-secret" make docker-test (an alternate Alpine-based NodeJS image can be provided via RUNTIME_IMAGE).

Documentation

• yarn doc will generate JSDoc documentation for the project.

Previewing upcoming functionality

If you want to preview unreleased features in your project, you can do so by installing this driver using one of the following methods.

1. Using a git URL

Normally, you would install the latest release of this package using npm install --save faunadb or yarn add faunadb. To access our latest features, you will need to define this dependency by using a git URL.

1. Open your package.json file

2. If you have already installed this driver, you should see the following in your list of dependencies. If not, add it.

"faunadb": "^2.14.1"

3. Instead of using a version from the npm registry, we'll want to point our package.json to the main branch of our GitHub repo. To do that, change the ^2.4.1 to fauna/faunadb-js#main.

"faunadb": "fauna/faunadb-js#main"

4. Update your node_modules by running npm install or yarn

2. Using npm pack

1. Clone this repo to your local system

git clone https://github.com/fauna/faunadb-js.git

2. Navigate to the cloned repo and open the package.json

cd faunadb-js
code package.json

3. Change the version to be semantic. For example, 3.0.0-beta.

4. Run npm pack. This creates a tarball at the root of your project directory which represents the image sent to the NPM registry when publishing.

5. In another project, you can now install the beta from the local image you just created by running:

npm install /path/to/tarball

License

Copyright 2023 Fauna, Inc.

Licensed under the Mozilla Public License, Version 2.0 (the "License"); you may not use this software except in compliance with the License. You may obtain a copy of the License at

https://mozilla.org/MPL/2.0/

Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.