Tags are used to logically group channels.

List Tags

To retrieve all of the tags in the Hub:

GET http://hub/tag

On success: HTTP/1.1 200 OK

{
  "_links" : {
    "self" : {
      "href" : "http://hub/tag"
    },
    "tags" : [ {
      "name" : "orders",
      "href" : "http://hub/tag/orders"
    }, {
      "name" : "coffee",
      "href" : "http://hub/tag/coffee"
    } ]
  }
}

Any of the returned tag links can be followed to see all of the channels with that tag:

GET http://hub/tag/coffee

On success: HTTP/1.1 200 OK

{
  "_links" : {
    "self" : {
      "href" : "http://hub/tag/coffee"
    },
    "latest": {
        "href": "http://hub/tag/coffee/latest"
    },
    "earliest": {
        "href": "http://hub/tag/coffee/earliest"
    },
    "time": {
        "href": "http://hub/tag/coffee/time"
    },
    "channels" : [ {
      "name" : "stumptown",
      "href" : "http://hub/channel/stumptown"
    }, {
      "name" : "spella",
      "href" : "http://hub/channel/spella"
    } ]
  }
}

tag unions

Tags can also be used for a read-only union set of all it’s channels. next and previous links, latest, earliest and time work the same as their channel analogs. Tag operations can be accessed through /tag/{tag-name} or /channel/{channel-name}/

Example operations:

GET http://hub/tag/coffee/latest
GET http://hub/tag/coffee/earliest
GET http://hub/tag/coffee/2015/06/25/16
GET http://hub/tag/coffee/2015/06/24/19/48/17/000/abc/previous
GET http://hub/tag/coffee/2015/06/24/19/48/17/000/abc/next/10
GET http://hub/channel/spella/2015/06/24/19/48/17/000/abc/next/10?tag=coffee

Operations through the channel interface (/channel/{channel-name}/) can a tag parameter. Using the tag parameter allows the user to stay in the tag context.

For example:

GET http://hub/tag/coffee/latest

returns a redirect to

http://hub/channel/spella/2015/06/24/19/48/17/000/abc?tag=coffee

Following the previous on that item and including the tag

http://hub/channel/spella/2015/06/24/19/48/17/000/abc/previous?tag=coffee

returns a redirect to an item on a different channel

http://hub/channel/stumptown/2015/06/24/19/40/17/000/qwe?tag=coffee