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JavaScriptWebWebNode.jsPhoneGapReactTitaniumVueJavaScript V4 Access Manager API Reference for Realtime Apps

PubNub Access Manager (PAM) extends PubNub's existing security framework by allowing developers to create and enforce secure access to channels and channel groups throughout the PubNub Real-Time Network.

As soon as Access Manager is enabled, no pub/sub-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.

Learn more about Access Manager here.

Grant

Requires Access Manager add-on XRequires that the Access Manager add-on is enabled for your key. See this page on enabling add-on features on your keys:

http://www.pubnub.com/knowledge-base/discussion/644/how-do-i-enable-add-on-features-for-my-keys.

Description

This function establishes access permissions for PubNub Access Manager (PAM) by setting the read or write attribute to true. A grant with read or write set to false (or not included) will revoke any previous grants with read or write set to true.
Permissions can be applied to any one of three levels:
  1. Application level privileges are based on subscribeKey applying to all associated channels.
  2. Channel level privileges are based on a combination of subscribeKey and channel name.
  3. User level privileges are based on the combination of subscribeKey, channel and auth Key.
 
For NTP synchronization, please ensure that you have configured NTP on your server to keep the clock in sync. This is to prevent system clock drift leading to 400 Invalid Timestamp error response.
https://support.pubnub.com/support/solutions/articles/14000043626-why-do-i-get-invalid-timestamp-when-i-try-to-grant-permission-using-access-manager-
How PAM rules are evaluated:
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:
  1. 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.
     

    Use application level grants with caution

    When access is granted on an application level, all channels and users will have access.

    Application level grants can also happen due to a bug in your code. e.g. Null parameters for channels and auth-keys can cause accidental application level grants.

  2. 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.
  3. User Level - 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.
 
If an argument of the grant is not provided, an expected default will be assumed.
  • read and write arguments default to false
  • no auth Key results in channel-level grant
  • no channel results in application-level grant
No Permissions - If no permissions were granted at any of the three levels, the user will be denied access to the PubNub resource and receive a 403 error message. This is the default behavior for a PAM enabled application.
 
Note that 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 userlevel should not grant access at either the Application or Channel levels.
Related Behavior:
  • History: To access historical messages you must grant full read access at either the subscribeKey or channel level. When a user has the appropriate permissions they can access any data stored. If they do not have access a 403 will be returned by PAM.
  • Presence: To grant access to Presence for a particular channel name you must also allow read and write access to the presence channel name which is specified by adding the -pnpres suffix to the name. Also note that a leave will fail in the case where a user's grant expires while connected. An HTTP 403 will be returned.
  • APNS: Standard permissions are required for publishing.
Duration of Permissions
The duration of permission set with grant() are controlled by setting a time-to-live(ttl). If a ttl is not specified it is automatically set to 1440 minutes by default. Once the ttl associated with an entry in PAM has expired, the read and write attributes are immediately set to false for that entry in the PAM table.
 
PAM grant or revoke requests must be less than ~32KB at a time, or the client will return an error. For requests greater than 32KB, break them into smaller batched requests.
 
When the message size exceeds 32KB the server returns the HTTP Error code 500, instead of the correct error code 414.
 
When you init with secretKey, you get root permissions for the Access Manager. With this feature you don't have to grant access to your servers to access channel data. The servers get all access on all channels.
 The limit on the total amount of channels that you can pass at once when using grant() is 200.

Method(s)

To Grant Permissions on a Channel you can use the following method(s) in the JavaScript V4 SDK:
  1. ParameterTypeRequiredDefaultsDescription
    Operation ArgumentsHashYesA hash of arguments.
    channels Array Specifying either channels or channelGroups is mandatory.Specifies the channels on which to grant permissions.
    If no channels/channelGroups are specified, then the grant applies to any and 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 is possible to grant permissions to multiple channels simultaneously by specifying the channels as a comma separated list.

    Wildcard notation like a.* can be used to grant access on channels. You can grant one level deep.
    • a.* - you can grant on this.
    • a.b.* - grant will not work on this. If you grant on a.b.*, the grant will treat a.b.* as a single channel with name a.b.*.
    channelGroups ArraySpecifying either channels or channelGroups is mandatory.Specifies the channelGroups to grant permissions. If no channels/channelGroups are specified, then the grant applies to any and 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 is possible to grant permissions to multiple channelGroups simultaneously by specifying the channelGroups as a comma separated list.
    authKeysArray OptionalSpecifies auth Key to grant permissions.
    It is possible to specify multiple auth keys as comma separated list in combination with a single channel name.
    You can also grant access to a single auth key for multiple channels at the same time.
    Zero or more channels with zero or more auth tokens are allowed.
    ttl Number Yes1440 (24hrs)Time in minutes for which granted permissions are valid. Default is 1440 (24hrs), Max is 525600 , Min is 1. Setting ttl to 0 will apply the grant indefinitely.
    read Boolean Yesfalse Read permissions are granted by setting to true. Read permissions are removed by setting to false.
    write Boolean Yes falseWrite permissions are granted by setting to true. Write permissions are removed by setting to false.
    manageBooleanYesfalseManage permissions are granted by setting to true. Manage permissions are removed by setting to false.
    callbackFunctionOptionalExecutes on a successful/unsuccessful grant.

Basic Usage

Grant PAM Permissions for channel and auth Key
pubnub.grant(
    {
        channels: [ch1, ch2],
        channelGroups: [cg1, cg2],
        authKeys: [key1, key2],
        ttl: 12313, // 0 for infinite
        read: true, // false to disallow
        write: true, // false to disallow
        manage: true // false to disallow
    },
    function (status) {
        // handle state setting response
    }
);

Other Examples

  1. Grant subscribe privileges to all users on all channel(s) with default ttl (1440 minutes):
    // grant world read access to all channels

pubnub.grant({
    read: true
});
  2. Allow subscribe and publish to a specific channel for all users (no auth Key required) with default ttl (1440 minutes):
    pubnub.grant(
    {
        channels: ['my_channel'],
        read: true, // false to disallow
        write: true // false to disallow
    },
    function (status) {
        console.log(status);
    }
);
  3. Grant subscribe access to a channel only for clients with a specific auth Key with a 5 minute ttl:
    pubnub.grant(
    {
        channels: ['my_channel'],
        authKeys: ['my_ro_authkey'],
        ttl: 5, // 0 for infinite
        read: true, // false to disallow
        write: false // false to disallow
    }, 
    function (status) {
        console.log(status);
    }
);
    The above code would return the following response to the client:
    {
    error: false,
    operation: 'PNAccessManagerGrant',
    statusCode: 200
}
  4. Allow access to a specific channel for Presence:
    pubnub.grant(
    {
        channels: ['my_channel-pnpres'],
        ttl: 5, // 0 for infinite
        read: true, // false to disallow
        write: true // false to disallow
    }, 
    function (status) {
        console.log(status);
    }
);
  5. Allow access to all channel groups using wildcard:
    To perform a first level wildcard grant for channel groups you need to specify : (colon) as the parameter for channelGroups. This will ensure that users can read or manage all channel groups.
    pubnub.grant(
    {
        channelGroups: [':'],
        read: true, 
        manage: true
    },
    function (status) {
        console.log(status);
    }
);
  6. Application Level Grant
     

    Use application level grants with caution

    When access is granted on an application level, all channels and users will have access.

    Application level grants can also happen due to a bug in your code. e.g. Null parameters for channels and auth-keys can cause accidental application level grants.

    pubnub.grant(
    {
        read: true, // false to disallow
        write: true // false to disallow
    },
    function (status) {
        console.log(status);
    }
);
  7. Channel Level Grant
    pubnub.grant(
    {
        channels: ['ch1'],
        read: true, // false to disallow
        write: true // false to disallow
    },
    function (status) {
        console.log(status);
    }
);
  8. User Level Grant
    pubnub.grant(
    {
        channels: ['ch1'],
        authKeys: ['key1'],
        read: true, // false to disallow
        write: true // false to disallow
    },
    function (status) {
        console.log(status);
    }
);