AWS::Events::EventBusPolicy - AWS CloudFormation

AWS::Events::EventBusPolicy

Running PutPermission permits the specified AWS account or AWS organization to put events to the specified event bus. Amazon EventBridge (CloudWatch Events) rules in your account are triggered by these events arriving to an event bus in your account.

For another account to send events to your account, that external account must have an EventBridge rule with your account's event bus as a target.

To enable multiple AWS accounts to put events to your event bus, run PutPermission once for each of these accounts. Or, if all the accounts are members of the same AWS organization, you can run PutPermission once specifying Principal as "*" and specifying the AWS organization ID in Condition, to grant permissions to all accounts in that organization.

If you grant permissions using an organization, then accounts in that organization must specify a RoleArn with proper permissions when they use PutTarget to add your account's event bus as a target. For more information, see Sending and Receiving Events Between AWS Accounts in the Amazon EventBridge User Guide.

The permission policy on the event bus cannot exceed 10 KB in size.

Syntax

To declare this entity in your AWS CloudFormation template, use the following syntax:

JSON

{ "Type" : "AWS::Events::EventBusPolicy", "Properties" : { "Action" : String, "Condition" : Condition, "EventBusName" : String, "Principal" : String, "Statement" : Json, "StatementId" : String } }

YAML

Type: AWS::Events::EventBusPolicy Properties: Action: String Condition: Condition EventBusName: String Principal: String Statement: Json StatementId: String

Properties

Action

The action that you are enabling the other account to perform.

Required: No

Type: String

Minimum: 1

Maximum: 64

Pattern: events:[a-zA-Z]+

Update requires: No interruption

Condition

This parameter enables you to limit the permission to accounts that fulfill a certain condition, such as being a member of a certain AWS organization. For more information about AWS Organizations, see What Is AWS Organizations in the AWS Organizations User Guide.

If you specify Condition with an AWS organization ID, and specify "*" as the value for Principal, you grant permission to all the accounts in the named organization.

The Condition is a JSON string which must contain Type, Key, and Value fields.

Required: No

Type: Condition

Update requires: No interruption

EventBusName

The name of the event bus associated with the rule. If you omit this, the default event bus is used.

Required: No

Type: String

Minimum: 1

Maximum: 256

Pattern: [\.\-_A-Za-z0-9]+

Update requires: Replacement

Principal

The 12-digit AWS account ID that you are permitting to put events to your default event bus. Specify "*" to permit any account to put events to your default event bus.

If you specify "*" without specifying Condition, avoid creating rules that may match undesirable events. To create more secure rules, make sure that the event pattern for each rule contains an account field with a specific account ID from which to receive events. Rules with an account field do not match any events sent from other accounts.

Required: No

Type: String

Minimum: 1

Maximum: 12

Pattern: (\d{12}|\*)

Update requires: No interruption

Statement

A JSON string that describes the permission policy statement. You can include a Policy parameter in the request instead of using the StatementId, Action, Principal, or Condition parameters.

Required: No

Type: Json

Update requires: No interruption

StatementId

An identifier string for the external account that you are granting permissions to. If you later want to revoke the permission for this external account, specify this StatementId when you run RemovePermission.

Required: Yes

Type: String

Minimum: 1

Maximum: 64

Pattern: [a-zA-Z0-9-_]+

Update requires: Replacement

Return values

Ref

When you pass the logical ID of this resource to the intrinsic Ref function, Ref returns the event bus policy ID, such as EventBusPolicy-1aBCdeFGh2J3.

For more information about using the Ref function, see Ref.

Examples

Grant Permission to One Account

The following example grants permission to one AWS account with an account ID of 111122223333.

JSON

"SampleEventBusPolicy": { "Type": "AWS::Events::EventBusPolicy", "Properties": { "StatementId": "MyStatement", "Statement": { "Effect": "Allow", "Principal" : {"AWS" : "arn:aws:iam::123456789012:root"}, "Action": "events:PutEvents", "Resource": "arn:aws:events:us-east-1:111122223333:event-bus/default" } } }

YAML

SampleEventBusPolicy: Type: AWS::Events::EventBusPolicy Properties: StatementId: "MyStatement" Statement: Effect: "Allow" Principal: AWS: "arn:aws:iam::123456789012:root" Action: "events:PutEvents" Resource: "arn:aws:events:us-east-1:111122223333:event-bus/default"

Grant Permission to an Organization

The following example grants permission to all AWS accounts in the organization with an organization ID of o-1234567890.

JSON

"SampleEventBusPolicy": { "Type": "AWS::Events::EventBusPolicy", "Properties": { "StatementId": "MyStatement", "Statement": { "Effect": "Allow", "Principal" : {"AWS" : "arn:aws:iam::123456789012:root"}, "Action": "events:PutEvents", "Resource": "arn:aws:events:us-east-1:111122223333:event-bus/default", "Condition": { "StringEquals": {"aws:PrincipalOrgID": "o-1234567890"} } } } }

YAML

SampleEventBusPolicy: Type: AWS::Events::EventBusPolicy Properties: StatementId: "MyStatement" Statement: Effect: "Allow" Principal: AWS: "arn:aws:iam::123456789012:root" Action: "events:PutEvents" Resource: "arn:aws:events:us-east-1:111122223333:event-bus/default" Condition: StringEquals: "aws:PrincipalOrgID": "o-1234567890"

Deny policy using multiple principals and actions

The following example demonstrates a deny policy statement using multiple principals and actions.

JSON

"SampleDenyEventBusPolicy": { "Type": "AWS::Events::EventBusPolicy", "Properties": { "StatementId": "MyDenyStatement", "Statement": { "Effect": "Deny", "Principal" : {"AWS" : ["arn:aws:iam::123456789012:root", "arn:aws:iam::999988887777:user/bob"]}, "Action": [ "events:PutEvents", "events:PutRule" ], "Resource": "arn:aws:events:us-east-1:111122223333:event-bus/default", "Condition": { "StringEquals": {"aws:PrincipalOrgID": "o-1234567890"} } } } }

YAML

SampleEventBusPolicy: Type: AWS::Events::EventBusPolicy Properties: StatementId: "MyDenyStatement" Statement: Effect: "Deny" Principal: AWS: - "arn:aws:iam::123456789012:root" - "arn:aws:iam::999988887777:user/bob" Action: - "events:PutEvents" - "events:PutRule" Resource: "arn:aws:events:us-east-1:111122223333:event-bus/default" Condition: StringEquals: "aws:PrincipalOrgID": "o-1234567890"

Grant Permission to an Organization using a custom event bus

The following example grants permission to all AWS accounts in the organization with an organization ID of `o-1234567890` using a custom event bus.

JSON

"SampleCustomEventBus": { "Type": "AWS::Events::EventBus", "Properties": { "Name": "MyCustomEventBus" } }, "SampleCustomEventBusPolicy": { "Type": "AWS::Events::EventBusPolicy", "Properties": { "EventBusName": { "Ref": "SampleCustomEventBus" }, "StatementId": "MyCustomEventBusStatement", "Statement": { "Effect": "Allow", "Principal": { "AWS": "*" }, "Action": "events:PutEvents", "Resource": { "Fn::GetAtt": [ "SampleCustomEventBus", "Arn" ] } } } }

YAML

SampleCustomEventBus: Type: AWS::Events::EventBus Properties: Name: "MyCustomEventBus" SampleCustomEventBusPolicy: Type: AWS::Events::EventBusPolicy Properties: EventBusName: Ref: "SampleCustomEventBus" StatementId: "MyCustomEventBusStatement" Statement: Effect: "Allow" Principal: AWS: "*" Action: "events:PutEvents" Resource: !GetAtt "SampleCustomEventBus.Arn"