Setup and integration

What you will need

If you’d like to host your own version of converse.js or you would like to integrate it into your website, then you’ll need to set up and configure some more server components.

For example, if you want to allow chat accounts under your own domain (for example, the same domain as your website), then you will need to set up your own An XMPP server.

Besides an XMPP server, you also need a way for converse.js (which uses HTTP), to communicate with XMPP servers (which use XMPP).

For this, you’ll need A BOSH Connection Manager.

Lastly, if you want to maintain a single chat session for your website’s users, you’ll need to set up a BOSH session on your server, which converse.js can then connect to once the page loads. Please see the section: Single Session Support.

An XMPP server

Converse.js implements XMPP as its messaging protocol, and therefore needs to connect to an XMPP/Jabber server (Jabber is really just a synonym for XMPP).

You can connect to public XMPP servers like jabber.org but if you want to have session support you’ll have to set up your own XMPP server.

You can find a list of public XMPP servers/providers on xmpp.net and a list of servers that you can set up yourself on xmpp.org.

A BOSH Connection Manager

Your website and Converse.js use HTTP as protocol to communicate with the webserver. HTTP connections are stateless and usually shortlived.

XMPP on the other hand, is the protocol that enables instant messaging, and its connections are stateful and usually longer.

To enable a web application like Converse.js to communicate with an XMPP server, we need a proxy which acts as a bridge between these two protocols.

This is the job of a BOSH connection manager. BOSH (Bidirectional-streams Over Synchronous HTTP) is a protocol for allowing XMPP communication over HTTP. The protocol is defined in XEP-0206: XMPP Over BOSH.

Popular XMPP servers such as Ejabberd, prosody (mod_bosh) and OpenFire all include their own connection managers (but you usually have to enable them in the configuration).

However, if you intend to support multiple different servers (like https://conversejs.org does), then you’ll need a standalone connection manager.

For a standalone manager, see for example Punjab and node-xmpp-bosh.

The demo on the Converse.js homepage uses a connection manager located at https://conversejs.org/http-bind.

This connection manager is available for testing purposes only, please don’t use it in production.

Alternatively, Websocket support

Websockets provide an alternative means of connection to an XMPP server from your browser.

Websockets provide long-lived, bidirectional connections which do not rely on HTTP. Therefore BOSH, which operates over HTTP, doesn’t apply to websockets.

Prosody (from version 0.10) supports websocket connections, as does the node-xmpp-bosh connection manager.

Overcoming cross-domain request restrictions

Lets say your domain is example.org, but the domain of your connection manager is example.com.

HTTP requests are made by Converse.js to the connection manager via XmlHttpRequests (XHR). Until recently, it was not possible to make such requests to a different domain than the one currently being served (to prevent XSS attacks).

Luckily there is now a standard called CORS (Cross-origin resource sharing), which enables exactly that. Modern browsers support CORS, but there are problems with Internet Explorer < 10.

IE 8 and 9 partially support CORS via a proprietary implementation called XDomainRequest. There is a Strophe.js plugin which you can use to enable support for XDomainRequest when it is present.

In IE < 8, there is no support for CORS.

Instead of using CORS, you can add a reverse proxy in Apache/Nginx which serves the connection manager under the same domain as your website. This will remove the need for any cross-domain XHR support.

For example:

Assuming your site is accessible on port 80 for the domain mysite.com and your connection manager manager is running at someothersite.com/http-bind.

The bosh_service_url value you want to give Converse.js to overcome the cross-domain restriction is mysite.com/http-bind and not someothersite.com/http-bind.

Your nginx or apache configuration will look as follows:

Nginx

http {
    server {
        listen       80
        server_name  mysite.com;
        location ~ ^/http-bind/ {
            proxy_pass http://someothersite.com;
        }
    }
}

Apache

<VirtualHost *:80>
    ServerName mysite.com
    RewriteEngine On
    RewriteRule ^/http-bind(.*) http://someothersite.com/http-bind$1 [P,L]
</VirtualHost>

Single Session Support

It’s possible to enable shared sessions whereby users already logged in to your website will also automatically be logged in on the XMPP server,

Once a user is logged in, the session will be kept alive across page loads by way of the keepalive setting.

There are a few ways to let your users be automatically authenticated to an XMPP server once they’ve logged in to your site.

Option 1). Server-side authentication via BOSH prebinding

To prebind refers to a technique whereby your web application sets up an authenticated BOSH session with the XMPP server or a standalone BOSH connection manager.

Once authenticated, it receives RID and SID tokens which need to be passed on to converse.js upon pa. Converse.js will then attach to that same session using those tokens.

It’s called “prebind” because you bind to the BOSH session beforehand, and then later in the page you just attach to that session again.

The RID and SID tokens can be passed in manually when calling converse.initialize, but a more convenient way is to pass converse.js a prebind_url which it will call when it needs the tokens. This way it will be able to automatically reconnect whenever the connection drops, by simply calling that URL again to fetch new tokens.

Prebinding reduces network traffic and also speeds up the startup time for converse.js. Additionally, because prebind works with tokens, it’s not necessary for the XMPP client to know or store users’ passwords.

One potential drawback of using prebind is that in order to establish the authenticated BOSH session server-side, you’ll need to access and pass on the XMPP credentials server-side, which, unless you’re using tokens, means that you’ll need to store XMPP passwords in cleartext.

This is however not the case if you for example use LDAP or Active Directory as your authentication backend, since you could then configure your XMPP server to use that as well.

To prebind you will require a BOSH-enabled XMPP server for converse.js to connect to (see the bosh_service_url under Configuration variables) as well as a BOSH client in your web application (written for example in Python, Ruby or PHP) that will set up an authenticated BOSH session, which converse.js can then attach to.

Note

A BOSH server acts as a bridge between HTTP, the protocol of the web, and XMPP, the instant messaging protocol.

Converse.js can only communicate via HTTP (or websocket, in which case BOSH can’t be used). It cannot open TCP sockets to communicate to an XMPP server directly.

So the BOSH server acts as a middle man, translating our HTTP requests into XMPP stanzas and vice versa.

Jack Moffitt has a great blogpost about this and even provides an example Django application to demonstrate it.

When you authenticate to the XMPP server on your backend application (for example via a BOSH client in Django), you’ll receive two tokens, RID (request ID) and SID (session ID).

The Session ID (SID) is a unique identifier for the current session. This number stays constant for the entire session.

The Request ID (RID) is a unique identifier for the current request (i.e. page load). Each page load is a new request which requires a new unique RID. The best way to achieve this is to simply increment the RID with each page load.

You’ll need to configure converse.js with the prebind, keepalive and prebind_url settings.

Please read the documentation on those settings for a fuller picture of what needs to be done.

Example code for server-side prebinding

Option 2). Delegated authentication, also called external authentication

An alternative to BOSH prebinding is to generate temporary authentication tokens which are then sent to the XMPP server and which it in turn checks against some kind of external authentication provider (generally the same web-app that generated the tokens).

In this case, you could use the credentials_url setting, to specify a URL from which converse.js should fetch the username and token.

Option 3). Cryptographically signed tokens

A third potential option is to generate cryptographically signed tokens (e.g. HMAC tokens) which the XMPP server could authenticate by checking that they’re signed with the right key and that they conform to some kind of pre-arranged format.

In this case, you would also use the credentials_url setting, to specify a URL from which converse.js should fetch the username and token.