Coral

Online comments are broken. Our open-source commenting platform, Coral, rethinks how moderation, comment display, and conversation function, creating the opportunity for safer, smarter discussions around your work. Read more about Coral here.

Built with <3 by The Coral Project, a part of Vox Media.

Preview Coral easily by running Coral via a Heroku App:

Table of Contents

• Requirements
• Running
  • Docker
  • Source
  • Embed On Your Site
  • Single Sign On
    • SSO Login Prompts
  • Development
    • Email
    • Design Language System (UI Components)
• Configuration
• License

Requirements

• MongoDB >=3.6
• Redis >=3.2
• NodeJS >=10
• NPM >=6.7

Running

You can install Coral using Docker or via Source. We recommend Docker, as it provides the easiest deployment solution going forward, as all the dependencies are baked and shipped with the provided coralproject/talk:next image. When v5 releases to master, you'll be able to select it using coralproject/talk:5.

Docker

The easiest way to get started with Coral is through our published Docker image and provided example docker-compose.yml file. The following assumes that you have Docker and Docker Compose installed on your local machine:

• Install Docker: https://docs.docker.com/install/
• Install Docker Compose: https://docs.docker.com/compose/install/ (this is typically included in the Docker Desktop editions already)

# Create directories to persist the data in MongoDB and Redis.
mkdir -p data/{mongo,redis}

# Create the `docker-compose.yml` file to get started.
cat > docker-compose.yml <<EOF
version: "2"
services:
  talk:
    image: coralproject/talk:next
    restart: always
    ports:
      - "127.0.0.1:3000:5000"
    depends_on:
      - mongo
      - redis
    environment:
      - MONGODB_URI=mongodb://mongo:27017/coral
      - REDIS_URI=redis://redis:6379
      - SIGNING_SECRET=<replace me with something secret>
  mongo:
    image: mongo:3.6
    volumes:
      - ./data/mongo:/data/db
  redis:
    image: redis:3.2
    volumes:
      - ./data/redis:/data
EOF

# Start up Coral using Docker.
docker-compose up -d

Then head on over to http://localhost:3000 to install Coral!

Source

Coral requires NodeJS >=10, we recommend using nvm to help manage node versions: https://github.com/creationix/nvm.

# Clone and cd into the Coral directory.
git clone https://github.com/coralproject/talk.git
cd talk

# Install dependencies.
npm install

# Build the application dependencies.
# This might take a while.
npm run build

This should output all the compiled application code to ./dist.

Running Coral with default settings assumes that you have:

• MongoDB >=3.6 running on 127.0.0.1:27017
• Redis >=3.2 running on 127.0.0.1:6379

If you don't already have these databases running, you can execute the following assuming you have Docker installed on your local machine:

docker run -d -p 27017:27017 --restart always --name mongo mongo:3.6
docker run -d -p 6379:6379 --restart always --name redis redis:3.2

Then start Coral with:

# Start the server in production mode.
npm run start

Then head on over to http://localhost:3000 to install Coral!

Embed On Your Site

With Coral setup and running locally you can test embeding the comment stream with this sample embed script:

<div id="coral_thread"></div>
<script type="text/javascript">
(function() {
    var talk = document.createElement('script'); talk.type = 'text/javascript'; talk.async = true;
    var url = '{{ CORAL_DOMAIN_NAME }}';
    talk.src = '//' + url + '/assets/js/embed.js';
    talk.onload = function() {
        Coral.createStreamEmbed({
            id: "coral_thread",
            autoRender: true,
            rootURL: '//' + url,
        });
    };
    (document.getElementsByTagName('head')[0] || document.getElementsByTagName('body')[0]).appendChild(talk);
})();
</script>

NOTE: Replace the value of {{ CORAL_DOMAIN_NAME }} with the location of your running instance of Coral.

Single Sign On

In order to allow seamless connection to an existing authentication system, Coral utilizes the industry standard JWT Token to connect. To learn more about how to create a JWT token, see this introduction.

1. Visit: https://{{ CORAL_DOMAIN_NAME }}/admin/configure/auth
2. Scroll to the Login with Single Sign On section
3. Enable the Single Sign On Authentication Integration
4. Enable Allow Registration
5. Copy the string in the Key box
6. Click Save

NOTE: Replace the value of {{ CORAL_DOMAIN_NAME }} with the location of your running instance of Coral.

You will then have to generate a JWT with the following claims:

• jti (optional) - A unique ID for this particular JWT token. We recommend using a UUID for this value. Without this parameter, the logout functionality inside the embed stream will not work and you will need to call logout on the embed itself.
• exp (optional) - When the given SSO token should expire. This is specified as a unix time stamp in seconds. Once the token has expired, a new token should be generated and passed into Coral. Without this parameter, the logout functionality inside the embed stream will not work and you will need to call logout on the embed itself.
• iat (optional) - When the given SSO token was issued. This is required to utilize the automatic user detail update system. If this time is newer than the time we received the last update, the contents of the token will be used to update the user.
• user.id (required) - the ID of the user from your authentication system. This is required to connect the user in your system to allow a seamless connection to Coral.
• user.email (required) - the email address of the user from your authentication system. This is required to facilitate notification email's about status changes on a user account such as bans or suspensions.
• user.username (required) - the username that should be used when being presented inside Coral to moderators and other users.
• user.badges (optional) - array of strings to be displayed as badges beside username inside Coral, visible to other users and moderators. For example, to indicate a user's subscription status.
• user.role (optional) - one of "COMMENTER", "STAFF", "MODERATOR", "ADMIN". Will create/update Coral user with this role.

An example of the claims for this token would be:

{
  "jti": "151c19fc-ad15-4f80-a49c-09f137789fbb",
  "exp": 1572172094,
  "iat": 1562172094,
  "user": {
    "id": "628bdc61-6616-4add-bfec-dd79156715d4",
    "email": "bob@example.com",
    "username": "bob"
  }
}

With the claims provided, you can sign them with the Key obtained from the Coral administration panel in the previous steps with a HS256 algorithm. This token can be provided in the above mentioned embed code by adding it to the createStreamEmbed function:

Coral.createStreamEmbed({
  // Don't forget to include the parameters from the
  // "Embed On Your Site" section.
  accessToken: "{{ SSO_TOKEN }}",
});

Or by calling the login/logout method on the embed object:

var embed = Coral.createStreamEmbed({
  // Don't forget to include the parameters from the
  // "Embed On Your Site" section.
});

// Login the current embed with the generated SSO token.
embed.login("{{ SSO_TOKEN }}");

// Logout the user.
embed.logout();

SSO Login Prompts

In order to handle login prompts (e.g. a user clicks on the sign in button) you can listen to the loginPrompt event.

var embed = Coral.createStreamEmbed({
  // Don't forget to include the parameters from the
  // "Embed On Your Site" section.
  events: function(events) {
    events.on("loginPrompt", function() {
      // Redirect user to a login page.
      location.href = "http://example.com/login";
    });
  },
});

Development

Running Coral for development is very similar to installing Coral via Source as described above.

Coral requires NodeJS >=10, we recommend using nvm to help manage node versions: https://github.com/creationix/nvm.

# Clone and cd into the Coral directory.
git clone https://github.com/coralproject/talk.git
cd talk

# Install dependencies.
npm install

Running Coral with default settings assumes that you have:

• MongoDB >=3.6 running on 127.0.0.1:27017
• Redis >=3.2 running on 127.0.0.1:6379

If you don't already have these databases running, you can execute the following assuming you have Docker installed on your local machine:

docker run -d -p 27017:27017 --restart always --name mongo mongo:3.6
docker run -d -p 6379:6379 --restart always --name redis redis:3.2

We recommend installing watchman for better watch performance.

# On macOS, you can run the following with Homebrew.
brew update
brew install watchman

Then start Coral with:

# Run the server in development mode in order to facilitate auto-restarting and
# rebuilding when file changes are detected. This might take a while to fully run.
npm run watch

When the client code has been built, navigate to http://localhost:8080/install to start the installation wizard. Note: Ensure localhost:8080 is used in the permitted domains list.

To see the comment stream goto http://localhost:8080/.

To run linting and tests use the following commands:

# Run the linters.
npm run lint

# Run our unit and integration tests.
npm run test

Email

To test out the email sending functionality, you can run inbucket which provides a test SMTP server that can visualize emails in the browser:

docker run -d --name inbucket --restart always -p 2500:2500 -p 9000:9000 inbucket/inbucket

You can then configure the email server on Coral by setting the email settings in Configure -> Email in the admin:

Field	Value
From Address	community@test.com
Secure	No
Host	localhost
Port	2500
Authentication	No

Navigate to http://localhost:9000, click the "Monitor" tab. New emails received on this screen.

Design Language System (UI Components)

We use docz to document and develop our Design Language System. To start docz run:

# Make sure CSS types are generated.
# This is not required when `npm run watch` is already running.
npm run generate:css-types

# Run docz in development.
npm run docz -- dev

After compilation has finished you can access docz at http://localhost:3030/.

Configuration

The following environment variables can be set to configure the Coral Server. You can expose them in your shell via export NODE_ENV=development or by placing the variables in a .env file in the root of the project in a simple NODE_ENV=development format delimited by newlines.

• NODE_ENV - Can be one of production or development. All production deployments should use production. Defaults to production when ran with npm run start and development when run with npm run start:development.
• PORT - The port to listen for HTTP and Websocket requests. (Default 3000)
• MONGODB_URI - The MongoDB database URI to connect to. (Default mongodb://127.0.0.1:27017/coral)
• REDIS_URI - The Redis database URI to connect to. (Default redis://127.0.0.1:6379)
• REDIS_OPTIONS - A JSON string with optional configuration options to be used when connecting to Redis as specified in the ioredis documentation. (Default: {})
• SIGNING_SECRET - The shared secret to use to sign JSON Web Tokens (JWT) with the selected signing algorithm. 🚨 Don't forget to set this variable! 🚨 (Default: keyboard cat)
• SIGNING_ALGORITHM - The signing algorithm to use for signing JWT's. (Default HS256).
• LOGGING_LEVEL - The logging level that can be set to one of fatal, error, warn, info, debug, or trace. (Default info)
• STATIC_URI - The URI that static assets can be accessed from. This URI can be to a proxy that uses this Coral server on PORT as the upstream. Disabled by default.
• DISABLE_TENANT_CACHING - When true, all tenants will be loaded from the database when needed rather than keeping a in-memory copy in sync via published events on Redis. (Default false)
• DISABLE_MONGODB_AUTOINDEXING - When true, Coral will not perform indexing operations when it starts up. This can be desired when you've already installed Coral on the target MongoDB, but want to improve start performance. You should not use this parameter unless you know what you're doing! Upgrades may introduce additional indexes that the application relies on. (Default false)
• LOCALE - Specify the default locale to use for all requests without a locale specified. (Default en-US)
• ENABLE_GRAPHIQL - When true, it will enable the /graphiql even in production, use with care. (Default false)
• CONCURRENCY - The number of worker nodes to spawn to handle web traffic, this should be tied to the number of CPU's available. (Default os.cpus().length)
• DEV_PORT - The port where the Webpack Development server is running on. (Default 8080)
• METRICS_USERNAME - The username for Basic Authentication at the /metrics and /cluster_metrics endpoint.
• METRICS_PASSWORD - The password for Basic Authentication at the /metrics and /cluster_metrics endpoint.
• CLUSTER_METRICS_PORT - If CONCURRENCY is more than 1, the metrics are provided at this port under /cluster_metrics. (Default 3001)
• DISABLE_LIVE_UPDATES - When true, disables subscriptions for the comment stream for all stories across all tenants (Default false)
• WEBSOCKET_KEEP_ALIVE_TIMEOUT - A duration in a parsable format (e.g. 30 seconds , 1 minute) that should be used to send keep alive messages through the websocket to keep the socket alive (Default 30 seconds)
• TRUST_PROXY - When provided, it configures the "trust proxy" settings for Express (See https://expressjs.com/en/guide/behind-proxies.html)

License

Coral is released under the Apache License, v2.0.