Access Manager v2 API for PubNub Dart SDK

Beta release

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PubNub Access Manager (PAM) allows you to enforce secure controls for client access to resources within the PubNub network. With PAM, your servers can grant their clients access to individual PubNub resources for a limited duration, with the ability to extend access or add permissions for additional resources.

As soon as PAM is enabled, no publish/subscribe operations can be done without first explicitly providing an authorization token to the PubNub object. If an invalid token is provided, the requesting client will receive a Forbidden error.

For more information about PAM, refer to Managing Permissions with Access Manager.

Grant

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 grant method allows you to grant permissions for one or more resources to one or more authKeys. You may need to make multiple grant calls with an authKey so that you can specify explicit permissions for each channel, channelGroup and uuid resources. For common permissions, you can normally use a single request.

Privileges specifically granted to an application's subscribeKey always take precedence over privileges granted to channel or auth_key. Therefore an application that requires authentication at the user level should not grant access at either the Application or Channel levels. View the Grant Levels section for more details.

Permissions

The grant request allows your server to securely grant access for your clients on the following resources within the platform. Each resource allows a limited set of permissions that control the operations that can be performed by the clients. For permissions and API operations mapping information, refer to Managing Permissions with Access Manager

Resource	Permissions
`channel`	`read`, `write`, `get`, `manage`, `update`, `join`, `delete`
`uuid`	`get`, `update`, `delete`
`channelGroup`	`read`, `manage`

Wildcard Permissions

Wildcard notation allows you to grant permissions to multiple channels at a time and later revoke these permissions in the same manner. You can only go one level deep using wildcards. In other words:

a.* grants access on all channels that begin with a..
* or a.b.* won't work this way. If you grant on * or a.b.*, the grant treats * or a.b.* as a channel name, not a wildcard.

Wildcard revokes

You can revoke permissions with wildcards from one level deep, like a.*, only when you initially used wildcards to grant permissions to a.*.

Grant Levels

When a user attempts to access a PubNub resource, PAM will evaluate any existing rules using the following order of precedence before access to a channel is granted to the user:

Application Level - PAM privileges are always evaluated first at the Application level. If either read or write attribute is set to true for a subscribeKey, PAM will immediately grant access for that attribute without proceeding to check permissions at either Channel or User levels. If an attribute is set to false at the Application level, PAM proceeds to evaluate the attribute at the next most granular level.
Channel Level - After first verifying an attribute at the Application level, PAM evaluates the attribute at the Channel level. If an attribute is set to true for a combination of subscribeKey, and channel, PAM grants access for that attribute at the Channel level without proceeding to check whether there may be user level permissions.
User Level (Recommended) - As a final step PAM evaluates the attributes at the User level. If an attribute is set to true for subscribeKey, channel and auth_key, access is granted for that attribute. Similarly, user level grants also allow you granting an auth_key access to channelGroups and uuids. User level grants require auth_key and are the recommended approach if you need to manage permissions for individual users within your application. Each user should be assigned a unique auth_key and securely passed back to the user to perform operations on the platform.

Method(s)

To Grant Permissions on a Channel you can use the following method(s) in the Dart SDK:

pubnub.grant(
  Set<String> authKeys,
    {Set<String>? channels,
    Set<String>? channelGroups,
    Set<String>? uuids,
    bool? write,
    bool? read,
    bool? manage,
    bool? delete,
    bool? get,
    bool? update,
    bool? join,
    int? ttl,
    Keyset? keyset,
    String? using}
)

Parameter	Type	Required	Default	Description
`authKeys`	`Set<String>`	Optional		Specifies `authKey` to grant permissions to. It's possible to specify multiple auth keys. You can also grant access to a single `authKey` for multiple `channels` at the same time. Zero or more `channels` with zero or more `auth` tokens are allowed.
`channels`	`List<String>`	Optional		Specifies the `channels` on which to grant permissions. If no `channels`/`channelGroups` are specified, then the grant applies to all `channels`/`channelGroups` that have been or will be created for that publish/subscribe key set. Furthermore, any existing or future grants on specific `channels` are ignored, until the all `channels` grant is revoked. It's possible to grant permissions to multiple `channels` simultaneously. Wildcard notation like `a.` can be used to grant access on `channels`. You can grant one level deep. - `a.` - you can grant on this. - `` and `a.b.` - grant will not work on these levels. If you grant on `` or `a.b.`, the grant will treat `` or `a.b.` as a single channel named either `` or `a.b.`.
`channelGroups`	`List<String>`	Optional		Specifies the `channelGroups` to `grant` permissions. If no `channels`/`channelGroups` are specified, then the `grant` applies to all `channels`/`channelGroups` that have been or will be created for that publish/subscribe key set. Furthermore, any existing or future grants on specific `channelGroups` are ignored, until the `all channelGroups` grant is revoked. It's possible to `grant` permissions to multiple `channelGroups` simultaneously.
`write`	`Boolean`	Optional	`false`	Write permission.
`read`	`Boolean`	Optional	`false`	Read permission.
`manage`	`Boolean`	Optional	`false`	Manage permission.
`delete`	`Boolean`	Optional	`false`	Delete permission.
`get`	`Boolean`	Optional	`false`	Get permission.
`update`	`Boolean`	Optional	`false`	Update permission.
`join`	`Boolean`	Optional	`false`	Join permission.
`ttl`	`Long`	Optional	`Not set`	Time in minutes for which granted permissions are valid. Setting `ttl` to 0 will apply the grant indefinitely, which is also the default behavior.
`keyset`	`Keyset`	Optional	default keyset	Override for the PubNub default keyset configuration.
`using`	`String`	Optional		Keyset name from the `keysetStore` to be used for this method call.

Basic Usage

Grant PAM Permissions for channel and auth_key

var result = await pubnub.grant({'my_authKey'},
    channels: {'my_channel'}, read: true);

Returns

The grant() operation returns a PamGrantResult which contains the following properties:

Property Name	Type	Description
`warning`	Boolean	Warning status.
`message`	String	Information whether operation was successful or not.
`level`	String	Access rights level.
`ttl`	int	`ttl` of `grant`.
`permissions`	List	Access rights per resource.

Permission contains the following properties:

Property Name	Type	Description
`channel`	String	Channel name for which permission is set.
`uuid`	String	UUID for which permission is set.
`read`	Boolean	`true` if the resource has `read` rights.
`write`	Boolean	`true` if the resource has `write` rights.
`manage`	Boolean	`true` if the resource has `manage` rights.
`delete`	Boolean	`true` if the resource has `delete` rights.
`get`	Boolean	`true` if the resource has `get` rights.
`update`	Boolean	`true` if the resource has `update` rights.
`join`	Boolean	`true` if the resource has `join` rights.

Other Examples

Grant subscribe access to a channel only for clients with a specific auth_key with a 5 minute ttl:

var result = await pubnub.grant({'my_authKey'},
  channels: {'my_channel'}, read: true, write: false, ttl: 5);

The above code returns the following response to the client:

{
    "status" : 200,
    "message" : "Success",
    "payload" : {
        "ttl" : 5,
        "auths" : {
            "my_authkey" : {
                "r" : 1,
                "w" : 1,
                "m" : 0,
                "d" : 0,
                "g" : 0,
                "u" : 0,
                "j" : 0
            }
        },
        "subscribe_key" : "my_subkey",
        "channel" : "my_channel"
    },
    "service" : "Access Manager"
}

Allow access to a specific channel for Presence:

var result = await pubnub.grant({'my_authKey'},
  channels: {'my_channel-pnpres'}, read: true, write: true);

Grant PAM Permissions for channel group:

var result = await pubnub.grant({'my_authKey'},
  channelGroups: {'my_channelGroup'}, read: true, manage: true, ttl: 5);