This is a headless Briar peer that exposes a REST API with an integrated HTTP server instead of a traditional user interface. You can use this API to script the peer behavior or to develop your own user interface for it.

How to use

The REST API peer comes as a jar file and needs a Java Runtime Environment (JRE) that supports at least Java 8. It currently works only on GNU/Linux operating systems.

You can start the peer (and its API server) like this:

$ java -jar briar-headless/build/libs/briar-headless.jar

It is possible to put parameters at the end. Try --help for a list of options.

On the first start, it will ask you to create a user account:

$ java -jar briar-headless.jar
No account found. Let's create one!

Nickname: testuser
Password:

After entering a password, it will start up without further output. Use the -v option if you prefer more verbose logging.

By default, Briar creates a folder ~/.briar where it stores its database and other files. There you also find the authentication token which is required to interact with the API:

$ cat ~/.briar/auth_token
DZbfoUie8sjap7CSDR9y6cgJCojV+xUITTIFbgtAgqk=

You can test that things work as expected by running:

$ curl -H "Authorization: Bearer DZbfoUie8sjap7CSDR9y6cgJCojV+xUITTIFbgtAgqk=" http://127.0.0.1:7000/v1/contacts
[]

The answer is an empty JSON array, because you don't have any contacts. Note that the HTTP request sets an Authorization header with the bearer token. A missing or wrong token will result in a 401 response.

REST API

Listing all contacts

GET /v1/contacts

Returns a JSON array of contacts:

{
    "author": {
        "formatVersion": 1,
        "id": "y1wkIzAimAbYoCGgWxkWlr6vnq1F8t1QRA/UMPgI0E0=",
        "name": "Test",
        "publicKey": "BDu6h1S02bF4W6rgoZfZ6BMjTj/9S9hNN7EQoV05qUo="
    },
    "contactId": 1,
    "verified": true
}

Adding a contact

Not yet implemented

The only workaround is to add a contact to the Briar app running on a rooted Android phone and then move its database (and key files) to the headless peer.

Removing a contact

DELETE /v1/contacts/{contactId}

The {contactId} is the contactId of the contact (1 in the example above). It returns with a status code 200, if removal was successful.

Listing all private messages

GET /v1/messages/{contactId}

The {contactId} is the contactId of the contact (1 in the example above). It returns a JSON array of private messages:

{
    "contactId": 1,
    "groupId": "oRRvCri85UE2XGcSloAKt/u8JDcMkmDc26SOMouxr4U=",
    "id": "ZGDrlpCxO9v7doO4Bmijh95QqQDykaS4Oji/mZVMIJ8=",
    "local": true,
    "read": true,
    "seen": true,
    "sent": true,
    "text": "test",
    "timestamp": 1537376633850,
    "type": "PrivateMessage"
}

If local is true, the message was sent by the Briar peer instead of its remote contact.

Attention: There can messages of other types where the message text is null.

Writing a private message

POST /v1/messages/{contactId}

The text of the message should be posted as JSON:

{
  "text": "Hello World!"
}

Listing blog posts

GET /v1/blogs/posts

Returns a JSON array of blog posts:

{
    "author": {
        "formatVersion": 1,
        "id": "VNKXkaERPpXmZuFbHHwYT6Qc148D+KNNxQ4hwtx7Kq4=",
        "name": "Test",
        "publicKey": "NbwpQWjS3gHMjjDQIASIy/j+bU6NRZnSRT8X8FKDoN4="
    },
    "authorStatus": "ourselves",
    "id": "X1jmHaYfrX47kT5OEd0OD+p/bptyR92IvuOBYSgxETM=",
    "parentId": null,
    "read": true,
    "rssFeed": false,
    "text": "Test Post Content",
    "timestamp": 1535397886749,
    "timestampReceived": 1535397886749,
    "type": "post"
}

Writing a blog post

POST /v1/blogs/posts

The text of the blog post should be posted as JSON:

{
  "text": "Hello Blog World!"
}

Websocket API

The Briar peer uses a websocket to notify a connected API client about new events.

WS /v1/ws

Immediately after making the connection, you must send the authentication token as a message to the websocket. If you fail to do this, you will not receive messages on that socket.

In JavaScript, it would look like this:

var token = "DZbfoUie8sjap7CSDR9y6cgJCojV+xUITTIFbgtAgqk=";
var socket = new WebSocket("ws://localhost:7000/v1/ws");
socket.onopen = function(event) { socket.send(token); };
socket.onmessage = function(event) { console.log(event.data); }

Receiving new private messages

When the Briar peer receives a new private message, it will send a JSON object to connected websocket clients:

{
    "data": {
        "contactId": 1,
        "groupId": "oRRvCri85UE2XGcSloAKt/u8JDcMkmDc26SOMouxr4U=",
        "id": "JBc+ogQIok/yr+7XtxN2iQgNfzw635mHikNaP5QOEVs=",
        "local": false,
        "read": false,
        "seen": false,
        "sent": false,
        "text": "Test Message",
        "timestamp": 1537389146088,
        "type": "PrivateMessage"
    },
    "name": "ConversationMessageReceivedEvent",
    "type": "event"
}

Note that the JSON object in data is exactly what the REST API returns when listing private messages.