# CreateEventSubscription
Creates an event notification subscription. This action requires a topic ARN (Amazon Resource Name) created by either the Neptune console, the SNS console, or the SNS API. To obtain an ARN with SNS, you must create a topic in Amazon SNS and subscribe to the topic. The ARN is displayed in the SNS console.
You can specify the type of source (SourceType) you want to be notified of, provide a list of Neptune sources (SourceIds) that triggers the events, and provide a list of event categories (EventCategories) for events you want to be notified of. For example, you can specify SourceType = db-instance, SourceIds = mydbinstance1, mydbinstance2 and EventCategories = Availability, Backup.
If you specify both the SourceType and SourceIds, such as SourceType = db-instance and SourceIdentifier = myDBInstance1, you are notified of all the db-instance events for the specified source. If you specify a SourceType but do not specify a SourceIdentifier, you receive notice of the events for that source type for all your Neptune sources. If you do not specify either the SourceType nor the SourceIdentifier, you are notified of events generated from all Neptune sources belonging to your customer account.
## Request Parameters
For information about the parameters that are common to all actions, see [Common Parameters](CommonParameters.md).
** Enabled **
A Boolean value; set to **true** to activate the subscription, set to **false** to create the subscription but not active it.
Type: Boolean
Required: No
**EventCategories.EventCategory.N**
A list of event categories for a SourceType that you want to subscribe to. You can see a list of the categories for a given SourceType by using the **DescribeEventCategories** action.
Type: Array of strings
Required: No
** SnsTopicArn **
The Amazon Resource Name (ARN) of the SNS topic created for event notification. The ARN is created by Amazon SNS when you create a topic and subscribe to it.
Type: String
Required: Yes
**SourceIds.SourceId.N**
The list of identifiers of the event sources for which events are returned. If not specified, then all sources are included in the response. An identifier must begin with a letter and must contain only ASCII letters, digits, and hyphens; it can't end with a hyphen or contain two consecutive hyphens.
Constraints:
+ If SourceIds are supplied, SourceType must also be provided.
+ If the source type is a DB instance, then a `DBInstanceIdentifier` must be supplied.
+ If the source type is a DB security group, a `DBSecurityGroupName` must be supplied.
+ If the source type is a DB parameter group, a `DBParameterGroupName` must be supplied.
+ If the source type is a DB snapshot, a `DBSnapshotIdentifier` must be supplied.
Type: Array of strings
Required: No
** SourceType **
The type of source that is generating the events. For example, if you want to be notified of events generated by a DB instance, you would set this parameter to db-instance. if this value is not specified, all events are returned.
Valid values: `db-instance` \$1 `db-cluster` \$1 `db-parameter-group` \$1 `db-security-group` \$1 `db-snapshot` \$1 `db-cluster-snapshot`
Type: String
Required: No
** SubscriptionName **
The name of the subscription.
Constraints: The name must be less than 255 characters.
Type: String
Required: Yes
**Tags.Tag.N**
The tags to be applied to the new event subscription.
Type: Array of [Tag](API_Tag.md) objects
Required: No
## Response Elements
The following element is returned by the service.
** EventSubscription **
Contains the results of a successful invocation of the [DescribeEventSubscriptions](API_DescribeEventSubscriptions.md) action.
Type: [EventSubscription](API_EventSubscription.md) object
## Errors
For information about the errors that are common to all actions, see [Common Error Types](CommonErrors.md).
** EventSubscriptionQuotaExceeded **
You have exceeded the number of events you can subscribe to.
HTTP Status Code: 400
** SNSInvalidTopic **
The SNS topic is invalid.
HTTP Status Code: 400
** SNSNoAuthorization **
There is no SNS authorization.
HTTP Status Code: 400
** SNSTopicArnNotFound **
The ARN of the SNS topic could not be found.
HTTP Status Code: 404
** SourceNotFound **
The source could not be found.
HTTP Status Code: 404
** SubscriptionAlreadyExist **
This subscription already exists.
HTTP Status Code: 400
** SubscriptionCategoryNotFound **
The designated subscription category could not be found.
HTTP Status Code: 404
## See Also
For more information about using this API in one of the language-specific AWS SDKs, see the following:
+ [AWS Command Line Interface V2](https://docs.aws.amazon.com/goto/cli2/neptune-2014-10-31/CreateEventSubscription)
+ [AWS SDK for .NET V4](https://docs.aws.amazon.com/goto/DotNetSDKV4/neptune-2014-10-31/CreateEventSubscription)
+ [AWS SDK for C\$1\$1](https://docs.aws.amazon.com/goto/SdkForCpp/neptune-2014-10-31/CreateEventSubscription)
+ [AWS SDK for Go v2](https://docs.aws.amazon.com/goto/SdkForGoV2/neptune-2014-10-31/CreateEventSubscription)
+ [AWS SDK for Java V2](https://docs.aws.amazon.com/goto/SdkForJavaV2/neptune-2014-10-31/CreateEventSubscription)
+ [AWS SDK for JavaScript V3](https://docs.aws.amazon.com/goto/SdkForJavaScriptV3/neptune-2014-10-31/CreateEventSubscription)
+ [AWS SDK for Kotlin](https://docs.aws.amazon.com/goto/SdkForKotlin/neptune-2014-10-31/CreateEventSubscription)
+ [AWS SDK for PHP V3](https://docs.aws.amazon.com/goto/SdkForPHPV3/neptune-2014-10-31/CreateEventSubscription)
+ [AWS SDK for Python](https://docs.aws.amazon.com/goto/boto3/neptune-2014-10-31/CreateEventSubscription)
+ [AWS SDK for Ruby V3](https://docs.aws.amazon.com/goto/SdkForRubyV3/neptune-2014-10-31/CreateEventSubscription)