API¶

There are three API available in Dashkiosk:

a REST API to manipulate groups, dashboards and displays,

the change API which is a Socket.IO based API which broadcasts changes to subscriber,

the display API which is a Socket.IO based API which tells displays which URL they should display.

There is also an internal bus API.

REST API¶

The REST API is available on the /api endpoint. Only JSON is currently supported. On error, the HTTP error code is important and the error message is also encapsulated into a JSON object:

{
    "error": {
        "httpCode": 404,
        "message": "No display named \"CNDS0KD\".",
        "name": "NotFoundError",
        "stack": [
            "NotFoundError: No display named \"CNDS0KD\".",
            "    at dashkiosk/lib/models/display.js:154:15",
            "    at process._tickDomainCallback (node.js:459:13)",
            "    at process._tickFromSpinner (node.js:390:15)",
            "From previous event:",
            "    at new Promise (dashkiosk/node_modules/sequelize/node_modules/bluebird/js/main/promise.js:88:37)",
            "    at module.exports.CustomEventEmitter.then (dashkiosk/node_modules/sequelize/lib/emitters/custom-event-emitter.js:144:12)",
            "    at Function.Display.get (dashkiosk/lib/models/display.js:152:6)",
            "    at dashkiosk/lib/api/rest/displays.js:21:20",
            "    at callbacks (dashkiosk/node_modules/express/lib/router/index.js:164:37)",
            "    at param (dashkiosk/node_modules/express/lib/router/index.js:138:11)"
        ]
    },
    "message": "No display named \"CNDS0KD\".",
    "token": "1397254337651-5YHK0SFJRC"
}

The error attribute is only present in development mode. It can also be found in the logs thanks to the token attribute.

Displays¶

GET /api/display¶

The list of all known displays.

Example request:

GET /api/display HTTP/1.1
Accept: application/json

Example response:

HTTP/1.1 200 OK
Content-Type: application/json

{
  "3VZG6Y": {
      "connected": false,
      "description": null,
      "group": 1,
      "id": 2,
      "ip": null,
      "name": "3VZG6Y",
      "viewport": null
  },
  "51VRJ7": {
      "connected": false,
      "description": "Chromium",
      "group": 2,
      "id": 7,
      "ip": "127.0.0.1",
      "name": "51VRJ7",
      "viewport": null
  }
}

Status Codes

200 OK – no error

PUT /api/display/(name)¶

Modify the attributes of the display name.

Example request:

PUT /api/display/CNDS0K HTTP/1.1
Accept: application/json

{ "viewport": "1920x1080" }

Example response:

HTTP/1.1 200 OK
Content-Type: application/json

{
  "connected": true,
  "description": "Nexus 5 (localhost:9400)",
  "group": 2,
  "id": 5,
  "ip": null,
  "name": "CNDS0K",
  "viewport": "1920x1080"
}

Parameters

name – name of the display

JSON Parameters

description – new description for the display
viewport – new viewport for the display

Status Codes

200 OK – no error
404 Not Found – display not found

PUT /api/display/(name)/group/(int: id)¶

Attach the display name to the group id.

Example request:

PUT /api/display/CNDS0K/group/10 HTTP/1.1
Accept: application/json

Example response:

HTTP/1.1 200 OK
Content-Type: application/json

{
  "connected": false,
  "description": "Nexus 5 (localhost:9400)",
  "group": 10,
  "id": 5,
  "ip": null,
  "name": "CNDS0K",
  "viewport": "1920x1080"
}

Parameters

name – name of the display
id – ID of the group

Status Codes

200 OK – no error
404 Not Found – display or group not found

POST /api/display/(name)/action¶

Request an action on a display. Only if connected.

Example request:

POST /api/display/CNDS0K/action HTTP/1.1
Accept: application/json

{ "action": "reload" }

Example response:

HTTP/1.1 200 OK
Content-Type: application/json

{
  "connected": true,
  "description": "Nexus 5 (localhost:9400)",
  "group": 10,
  "id": 5,
  "ip": null,
  "name": "CNDS0K",
  "viewport": "1920x1080"
}

Parameters

name – name of the display

JSON Parameters

action – requested action, either reload or osd
text – for OSD only, text to display or null to remove the OSD

Status Codes

200 OK – no error
400 Bad Request – unknown action
404 Not Found – display not found or offline

DELETE /api/display/(name)¶

Delete the display name. Only possible if the display is not connected anymore.

Example request:

DELETE /api/display/CNDS0K HTTP/1.1
Accept: application/json

Example response:

HTTP/1.1 204 OK
Content-Type: application/json

Parameters

name – name of the display

Status Codes

204 No Content – no error
404 Not Found – display not found
409 Conflict – display still connected

Groups¶

GET /api/group¶

The list of all known groups.

Example request:

GET /api/group HTTP/1.1
Accept: application/json

Example response:

HTTP/1.1 200 OK
Content-Type: application/json

{
  "1": {
      "description": "Default group for unassigned displays",
      "id": 1,
      "name": "Unassigned"
  },
  "2": {
      "description": "Dashboards with Game of Thrones stuff",
      "id": 2,
      "name": "Game of Thrones"
  }
}

Status Codes

200 OK – no error

POST /api/group¶

Create a new group

Example request:

POST /api/group HTTP/1.1
Accept: application/json

{
  "name": "New group"
}

Example response:

HTTP/1.1 200 OK
Content-Type: application/json

{
  "id": 9,
  "name": "New group"
}

JSON Parameters

name – name of the group
description – description of the group

Status Codes

200 OK – no error
400 Bad Request – a group should have a name
409 Conflict – a group with the same name already exists

PUT /api/group/(int: id)¶

Modify a group attributes.

Example request:

PUT /api/group/15 HTTP/1.1
Accept: application/json

{
  "name": "Another name",
  "description": "Fancy"
}

Example response:

HTTP/1.1 200 OK
Content-Type: application/json

{
  "id": 9,
  "name": "Another name",
  "description": "Fancy"
}

JSON Parameters

name – name of the group
description – description of the group

Status Codes

200 OK – no error
409 Conflict – a group with the same name already exists

DELETE /api/group/(int: id)¶

Delete the group. Only possible if no display are attached.

Example request:

DELETE /api/group/15 HTTP/1.1
Accept: application/json

Example response:

HTTP/1.1 204 OK
Content-Type: application/json

Parameters

id – ID of the group

Status Codes

204 No Content – no error
404 Not Found – group not found
409 Conflict – group with displays

Dashboards¶

GET /api/group/(int: id)/dashboard¶

The list of all dashboards in a group

Example request:

GET /api/group/15/dashboard HTTP/1.1
Accept: application/json

Example response:

HTTP/1.1 200 OK
Content-Type: application/json

[
  {
      "active": false,
      "description": "House Stark",
      "group": 15,
      "id": 2,
      "timeout": 30,
      "url": "http://www.gameofthronescountdown.com/#stark",
      "viewport": null
  },
  {
      "active": true,
      "description": "House Tully",
      "group": 15,
      "id": 3,
      "timeout": 30,
      "url": "http://www.gameofthronescountdown.com/#tully",
      "viewport": null
  }
]

Parameters

id – group ID

Status Codes

200 OK – no error
404 Not Found – the group doesn’t exist

POST /api/group/(int: id)/dashboard¶

Create a new dashboard

Example request:

POST /api/group/15/dashboard HTTP/1.1
Accept: application/json

{
  "url": "http://www.example.com",
  "timeout": 30
}

Example response:

HTTP/1.1 200 OK
Content-Type: application/json

{
      "active": false,
      "group": 15,
      "id": 6,
      "timeout": 30,
      "url": "http://www.example.com"
}

Parameters

id – group ID

JSON Parameters

url – URL of the dashboard
description – description of the dashboard
timeout – timer for this dashboard
viewport – viewport for this dashboard

Status Codes

200 OK – no error
404 Not Found – group not found
409 Conflict – the URL is mandatory

PUT /api/group/(int: id)/dashboard/(int: dashid)¶

Modify an existing dashboard. The special attribute rank can be used to modify the position of the dashboard in the group. The dashboards are numbered from 0 and the rank is the target position we want.

Example request:

POST /api/group/15/dashboard/6 HTTP/1.1
Accept: application/json

{
  "timeout": 40
}

Example response:

HTTP/1.1 200 OK
Content-Type: application/json

{
      "active": false,
      "group": 15,
      "id": 6,
      "timeout": 40,
      "url": "http://www.example.com"
}

Parameters

id – group ID
dashid – dashboard ID

JSON Parameters

url – URL of the dashboard
description – description of the dashboard
timeout – timer for this dashboard
viewport – viewport for this dashboard
rank – New position for the dashboard

Status Codes

200 OK – no error
404 Not Found – dashboard or group not found

DELETE /api/group/(int: id)/dashboard(int: dashid)¶

Delete the dashboard.

Example request:

DELETE /api/group/15/dashboard/6 HTTP/1.1
Accept: application/json

Example response:

HTTP/1.1 204 OK
Content-Type: application/json

Parameters

id – ID of the group
dashid – ID of the dashboard

Status Codes

204 No Content – no error
404 Not Found – group or dashboard not found

Changes API¶

The socket.IO endpoint for this API is changes. Upon connection, a client will get all the current groups. Each group has a collection of displays in the displays attribute and an array of dashboards in the dashboards attribute. Here is an example:

{
  "1": {
      "description": "Default group for unassigned displays",
      "id": 1,
      "name": "Unassigned",
      "displays": {},
      "dashboards": []
  },
  "2": {
      "description": "Dashboards with Game of Thrones stuff",
      "id": 2,
      "name": "Game of Thrones"
      "displays": {
         "CNDS0K": {
            "connected": true,
            "description": "Nexus 5 (localhost:9400)",
            "group": 10,
            "id": 5,
            "ip": null,
            "name": "CNDS0K",
            "viewport": "1920x1080"
         }
       }
      "dashboards": [
            {
              "active": false,
              "description": "House Stark",
              "group": 2,
              "id": 2,
              "timeout": 30,
              "url": "http://www.gameofthronescountdown.com/#stark",
              "viewport": null
            },
            {
              "active": true,
              "description": "House Tully",
              "group": 2,
              "id": 3,
              "timeout": 30,
              "url": "http://www.gameofthronescountdown.com/#tully",
              "viewport": null
            }
      ]
  }
}

This message will be labeled snapshot.

On changes, only the group or the display affected by the change will be sent. The label of the message will be one of:

group.deleted

group.updated

group.created

And for displays:

display.deleted

display.updated (also for new displays)

If a change affects a dashboard, the whole group will be sent nonetheless.

Display API¶

This API is used by the display to know what they should do. The socket.IO endpoint to use for it is displays.

The server attributes to each new display a serial number. The display is expected to remember it and transmit it back on the next connection. It is encrypted by the server to avoid the display to steal another display identity.

Upon connection, a display is expected to send a register message with an object containing the blob attribute with the encrypted identity it previously received (if any).

If the server accepts the identity as is, it answers to this message with the same blob that should be stored by the client. If not, it will generate a new blob and sends it back to the client. In both cases, the client just has to store the received blob.

After this handshake, the display can receive the following messages:

dashboard
The dashboard that should be displayed right now. It is an object containing the same attributes as we would have got when requesting this particular dashboard with the REST API. See Dashboards.

reload
The display should reload itself.

osd
The OSD should be shown or hidden. If the message comes with a text, the OSD is displayed with the provided text. Otherwise, it is hidden.

viewport
Modify the current viewport of the display with the provided value.

Internal bus message¶

To avoid strong coupling between components, Dashkiosk uses postal.js as an internal bus message. The messages that are emitted are listed below:

display.NAME.connected when a new display is connected

display.NAME.disconnected when a new display is disconnected

display.NAME.group when a display should change to a new group

display.NAME.deleted when a display is deleted

display.NAME.updated when another change happens on a display

display.NAME.dashboard when a new dashboard should be displayed by the given display.

display.NAME.reload when a display should reload itself

display.NAME.osd when we need to display something on the OSD

display.NAME.viewport when the display viewport should be updated

group.ID.created when a new group is created

group.ID.updated when a group is updated (but not something dashboard related)

group.ID.deleted when a group is deleted

group.ID.dashboard when a whole group should switch to a new dashboard

group.ID.dashboard.ID.added when a new dashboard has been added

group.ID.dashboard.ID.removed when a dashboard has been removed

group.ID.dashboard.ID.updated when a dashboard has been updated

Each message comes with the group, the dashboard and/or the display specified in the message (when this is relevant).