Access Manager v3 API for PubNub Kotlin SDK

Access Manager allows you to enforce security controls for client access to resources within the PubNub Platform. With Access Manager v3, your servers can grant their clients tokens with embedded permissions that provide access to individual PubNub resources:

• For a limited period of time.
• Through resource lists or patterns (regular expressions).
• In a single API request, even if permission levels differ (read to channel1 and write to channel2).

You can add the authorized_uuid parameter to the grant request to restrict the token usage to one client with a given uuid. Once specified, only this authorized_uuid will be able to use the token to make API requests for the specified resources, according to permissions given in the grant request.

For more information about Access Manager v3, refer to Manage Permissions with Access Manager v3.

Calling Kotlin methods

Most PubNub Kotlin SDK method invocations return an Endpoint object, which allows you to decide whether to perform the operation synchronously or asynchronously. You must choose one of these or the operation will not be performed at all.

For example, the following code is valid and will compile, but the publish won't be performed:

pubnub.publish(
    message = "this sdk rules!",
    channel = "my_channel"
)

To successfully publish a message, you must follow the actual method invocation with whether to perform it synchronously or asynchronously, for example:

pubnub.publish(
    message = "this sdk rules!",
    channel = "my_channel"
).async { result, status ->
    if (status.error) {
        // Handle error
    } else {
        // Handle successful method result
    }
}

Grant Token

Requires Access Manager add-onRequires that the Access Manager add-on is enabled for your key. See this page on enabling add-on features on your keys:
https://support.pubnub.com/hc/en-us/articles/360051974791-How-do-I-enable-add-on-features-for-my-keys-

The grantToken() method generates a time-limited authorization token with an embedded access control list. The token defines time to live (ttl), authorizedUUID, and a set of permissions giving access to one or more resources:

• channels
• channelGroups
• uuids (other users' object metadata, such as their names or avatars)

Only this authorizedUUID will be able to use the token with the defined permissions. The authorized client will send the token to PubNub with each request until the token's ttl expires. Any unauthorized request or a request made with an invalid token will return a 403 with a respective error message.

Revokes

Access Manager v3 doesn't support revokes yet. For now, you can override existing access by requesting a new token with changed permissions. Previous access will be removed once the original token expires. For this reason, it's recommended to use short-lived tokens with ttl between 10 and 60 minutes.

Permissions

The grant request allows your server to securely grant your clients access to the resources within the PubNub Platform. There is a limited set of operations the clients can perform on every resource:

Resource	Permissions
channel	read, write, get, manage, update, join, delete
channelGroups	read, manage
uuids	get, update, delete

For permissions and API operations mapping, refer to Manage Permissions with Access Manager v3.

TTL

The ttl (time to live) parameter is the number of minutes before the granted permissions expire. The client will require a new token to be granted before expiration to ensure continued access. ttl is a required parameter for every grant call and there is no default value set for it. For security reasons, it's recommended to set ttl between 10 and 60, and create a new token before this ttl elapses.

For more details, see TTL in Access Manager v3.

RegEx

If you prefer to specify permissions by setting patterns, rather than listing all resources one by one, you can use regular expressions. To do this, set RegEx permissions as patterns before making a grant request.

For more details, see RegEx in Access Manager v3.

Authorized UUID

Setting an authorizedUUID in the token helps you specify which client device should use this token in every request to PubNub. This will ensure that all requests to PubNub are authorized before PubNub processes them. If authorizedUUID isn't specified during the grant request, the token can be used by any client with any uuid. It's recommended to restrict tokens to a single authorizedUUID to prevent impersonation.

For more details, see Authorized UUID in Access Manager v3.

Method(s)

grantToken(
  ttl: Integer,
  meta: Any,
  authorizedUUID: String,
  channels: List<ChannelGrant>
  channelGroups: List<ChannelGroupGrant>
  uuids: List<UUIDGrant>)

Parameter	Type	Required	Default	Description
ttl	Number	Yes	n/a	Total number of minutes for which the token is valid. The minimum allowed value is 1. The maximum is 43,200 minutes (30 days).
meta	Object	Optional	n/a	Extra metadata to be published with the request. Values must be scalar only; arrays or objects are not supported.
authorizedUUID	String	Optional	n/a	Single uuid which is authorized to use the token to make API requests to PubNub.
channels	list<Channel>	Optional	n/a	All channel grants provided either as a list or a RegEx pattern.
channelGroups	list<ChannelGroupGrant>	Optional	n/a	All channel group grants provided either as a list or a RegEx pattern.
uuids	list<UUIDGrant>	Optional	n/a	All uuid grants provided either as a list or a RegEx pattern.

Required key/value mappings

For a successful grant request, you must specify permissions for at least one uuid, channel, or channelGroup, either as a resource list or as a pattern (RegEx).

Basic Usage

pubnub.grantToken(ttl = 15,
  authorizedUUID = "my-authorized-uuid",
  channels = listOf(ChannelGrant.name(name = "my-channel", read = true)))
  .async { result, status -> 
      if (status.error()) {
        // Handle error
      } else {
        // Handle result
      }
  }

Returns

{"token":"p0thisAkFl043rhDdHRsCkNyZXisRGNoYW6hanNlY3JldAFDZ3Jwsample3KgQ3NwY6BDcGF0pERjaGFuoENnctokenVzcqBDc3BjoERtZXRhoENzaWdYIGOAeTyWGJI"}

Other Examples

1. Grant an authorized client different levels of access to various resources in a single call:

   The code below grants my-authorized-uuid:

   • Read access to channel-a, channel-group-b, and get to uuid-c.
   • Read/write access to channel-b, channel-c, channel-d, and get/update to uuid-d.

   pubnub.grantToken(ttl = 15,
   authorizedUUID = "my-authorized-uuid",
   channels = listOf(
           ChannelGrant.name(name = "channel-a", read = true),
           ChannelGrant.name(name = "channel-b", read = true, write = true),
           ChannelGrant.name(name = "channel-c", read = true, write = true),
           ChannelGrant.name(name = "channel-d", read = true, write = true)),
   channelGroups = listOf(
           ChannelGroupGrant.id(id = "channel-group-b", read = true)),
   uuids = listOf(
           UUIDGrant.id(id = "uuid-c", get = true),
           UUIDGrant.id(id = "uuid-d", get = true, update = true)))
   .async { result, status -> 
       if (status.error()) {
           // Handle error
       } else {
           // Handle result
       }
   }
   

2. Grant an authorized client read access to multiple channels using RegEx:

   The code below grants my-authorized-uuid read access to all channels that match the channel-[A-Za-z0-9] RegEx pattern.

   pubnub.grantToken(ttl = 15,
   authorizedUUID = "my-authorized-uuid",
   channels = listOf(
           ChannelGrant.pattern(pattern = "^channel-[A-Za-z0-9]*$", read = true)))
   .async { result, status -> 
       if (status.error()) {
           // Handle error
       } else {
           // Handle result
       }
   }
   

3. Grant an authorized client different levels of access to various resources and read access to channels using RegEx in a single call:

   The code below grants the my-authorized-uuid:

   • Read access to channel-a, channel-group-b, and get to uuid-c.
   • Read/write access to channel-b, channel-c, channel-d, and get/update to uuid-d.
   • Read access to all channels that match the channel-[A-Za-z0-9] RegEx pattern.

   pubnub.grantToken(ttl = 15,
   authorizedUUID = "my-authorized-uuid",
   channels = listOf(
           ChannelGrant.name(name = "channel-a", read = true),
           ChannelGrant.name(name = "channel-b", read = true, write = true),
           ChannelGrant.name(name = "channel-c", read = true, write = true),
           ChannelGrant.name(name = "channel-d", read = true, write = true),
           ChannelGrant.pattern(pattern = "^channel-[A-Za-z0-9]*$", read = true)),
   channelGroups = listOf(
           ChannelGroupGrant.id(id = "channel-group-b", read = true)),
   uuids = listOf(
           UUIDGrant.id(id = "uuid-c", get = true),
           UUIDGrant.id(id = "uuid-d", get = true, update = true)))
   .async { result, status -> 
       if (status.error()) {
           // Handle error
       } else {
           // Handle result
       }
   }
   

Error responses

If you submit an invalid request, the server returns the 400 error status code with a descriptive message informing which of the provided arguments is missing or incorrect. These can include, for example, issues with a RegEx, a timestamp, or permissions. The server returns the details of the error as a string under the PubNubException class.

Parse Token

The parseToken() method decodes an existing token and returns the object containing permissions embedded in that token. The client can use this method for debugging to check the permissions to the resources or find out the token's ttl details.

Method(s)

parseToken(String token)

Parameter	Type	Required	Default	Description
token	String	Yes	n/a	Current token with embedded permissions.

Basic Usage

pubnub.parseToken("p0thisAkFl043rhDdHRsCkNyZXisRGNoYW6hanNlY3JldAFDZ3Jwsample3KgQ3NwY6BDcGF0pERjaGFuoENnctokenVzcqBDc3BjoERtZXRhoENzaWdYIGOAeTyWGJI")

Returns

{
   "version":2,
   "timestamp":1629394579,
   "ttl":15,
   "authorized_uuid": "user1",
   "resources":{
      "uuids":{
         "user1":{
            "read":false,
            "write":false,
            "manage":false,
            "delete":false,
            "get":true,
            "update":true,
            "join":false
         }
      },
      "channels":{
         "channel1":{
            "read":true,
            "write":true,
            "manage":false,
            "delete":false,
            "get":false,
            "update":false,
            "join":false
         }
      },
      "groups":{
         "group1":{
            "read":true,
            "write":false,
            "manage":false,
            "delete":false,
            "get":false,
            "update":false,
            "join":false
         }
      }
   },
   "patterns":{
      "uuids":{
         ".*":{
            "read":false,
            "write":false,
            "manage":false,
            "delete":false,
            "get":true,
            "update":false,
            "join":false
         }
      },
      "channels":{
         ".*":{
            "read":true,
            "write":true,
            "manage":false,
            "delete":false,
            "get":false,
            "update":false,
            "join":false
         }
      },
      "groups":{
         ".*":{
            "read":true,
            "write":false,
            "manage":false,
            "delete":false,
            "get":false,
            "update":false,
            "join":false
         }
      }
   }
}

Error Responses

If you receive an error while parsing the token, it may suggest that the token is damaged. In that case, request the server to issue a new one.

Set Token

The setToken() method is used by the client devices to update the authentication token granted by the server.

Method(s)

setToken(String token)

Parameter	Type	Required	Default	Description
token	String	Yes	n/a	Current token with embedded permissions.

Basic Usage

pubnub.setToken("p0thisAkFl043rhDdHRsCkNyZXisRGNoYW6hanNlY3JldAFDZ3Jwsample3KgQ3NwY6BDcGF0pERjaGFuoENnctokenVzcqBDc3BjoERtZXRhoENzaWdYIGOAeTyWGJI")

Returns

This method doesn't return any response value.