Rule¶

class aws_cdk.aws_events.Rule(scope, id, *, description=None, enabled=None, event_bus=None, event_pattern=None, rule_name=None, schedule=None, targets=None)¶

Bases: aws_cdk.core.Resource

Defines an EventBridge Rule in this stack.

ExampleMetadata: infused
Resource: AWS::Events::Rule

Example:

import aws_cdk.aws_lambda as lambda_


fn = lambda_.Function(self, "MyFunc",
    runtime=lambda_.Runtime.NODEJS_12_X,
    handler="index.handler",
    code=lambda_.Code.from_inline("exports.handler = handler.toString()")
)

rule = events.Rule(self, "rule",
    event_pattern=events.EventPattern(
        source=["aws.ec2"]
    )
)

queue = sqs.Queue(self, "Queue")

rule.add_target(targets.LambdaFunction(fn,
    dead_letter_queue=queue,  # Optional: add a dead letter queue
    max_event_age=cdk.Duration.hours(2),  # Optional: set the maxEventAge retry policy
    retry_attempts=2
))

Parameters

scope (Construct) –
id (str) –
description (Optional[str]) – A description of the rule’s purpose. Default: - No description.
enabled (Optional[bool]) – Indicates whether the rule is enabled. Default: true
event_bus (Optional[IEventBus]) – The event bus to associate with this rule. Default: - The default event bus.
event_pattern (Optional[EventPattern]) – Describes which events EventBridge routes to the specified target. These routed events are matched events. For more information, see Events and Event Patterns in the Amazon EventBridge User Guide. Default: - None.
rule_name (Optional[str]) – A name for the rule. Default: - AWS CloudFormation generates a unique physical ID and uses that ID for the rule name. For more information, see Name Type.
schedule (Optional[Schedule]) – The schedule or rate (frequency) that determines when EventBridge runs the rule. For more information, see Schedule Expression Syntax for Rules in the Amazon EventBridge User Guide. Default: - None.
targets (Optional[Sequence[IRuleTarget]]) – Targets to invoke when this rule matches an event. Input will be the full matched event. If you wish to specify custom target input, use addTarget(target[, inputOptions]). Default: - No targets.

Methods

add_event_pattern(*, account=None, detail=None, detail_type=None, id=None, region=None, resources=None, source=None, time=None, version=None)¶

Adds an event pattern filter to this rule.

If a pattern was already specified, these values are merged into the existing pattern.

For example, if the rule already contains the pattern:

{
  "resources": [ "r1" ],
  "detail": {
    "hello": [ 1 ]
  }
}

And addEventPattern is called with the pattern:

{
  "resources": [ "r2" ],
  "detail": {
    "foo": [ "bar" ]
  }
}

The resulting event pattern will be:

{
  "resources": [ "r1", "r2" ],
  "detail": {
    "hello": [ 1 ],
    "foo": [ "bar" ]
  }
}

Parameters

account (Optional[Sequence[str]]) – The 12-digit number identifying an AWS account. Default: - No filtering on account
detail (Optional[Mapping[str, Any]]) – A JSON object, whose content is at the discretion of the service originating the event. Default: - No filtering on detail
detail_type (Optional[Sequence[str]]) – Identifies, in combination with the source field, the fields and values that appear in the detail field. Represents the “detail-type” event field. Default: - No filtering on detail type
id (Optional[Sequence[str]]) – A unique value is generated for every event. This can be helpful in tracing events as they move through rules to targets, and are processed. Default: - No filtering on id
region (Optional[Sequence[str]]) – Identifies the AWS region where the event originated. Default: - No filtering on region
resources (Optional[Sequence[str]]) – This JSON array contains ARNs that identify resources that are involved in the event. Inclusion of these ARNs is at the discretion of the service. For example, Amazon EC2 instance state-changes include Amazon EC2 instance ARNs, Auto Scaling events include ARNs for both instances and Auto Scaling groups, but API calls with AWS CloudTrail do not include resource ARNs. Default: - No filtering on resource
source (Optional[Sequence[str]]) – Identifies the service that sourced the event. All events sourced from within AWS begin with “aws.” Customer-generated events can have any value here, as long as it doesn’t begin with “aws.” We recommend the use of Java package-name style reverse domain-name strings. To find the correct value for source for an AWS service, see the table in AWS Service Namespaces. For example, the source value for Amazon CloudFront is aws.cloudfront. Default: - No filtering on source
time (Optional[Sequence[str]]) – The event timestamp, which can be specified by the service originating the event. If the event spans a time interval, the service might choose to report the start time, so this value can be noticeably before the time the event is actually received. Default: - No filtering on time
version (Optional[Sequence[str]]) – By default, this is set to 0 (zero) in all events. Default: - No filtering on version

Return type

None

add_target(target=None)¶

Adds a target to the rule. The abstract class RuleTarget can be extended to define new targets.

No-op if target is undefined.

Parameters

target (Optional[IRuleTarget]) –

Return type

None

apply_removal_policy(policy)¶

Apply the given removal policy to this resource.

The Removal Policy controls what happens to this resource when it stops being managed by CloudFormation, either because you’ve removed it from the CDK application or because you’ve made a change that requires the resource to be replaced.

The resource can be deleted (RemovalPolicy.DESTROY), or left in your AWS account for data recovery and cleanup later (RemovalPolicy.RETAIN).

Parameters

policy (RemovalPolicy) –

Return type

None

to_string()¶

Returns a string representation of this construct.

Return type: str

Attributes

env¶

The environment this resource belongs to.

For resources that are created and managed by the CDK (generally, those created by creating new class instances like Role, Bucket, etc.), this is always the same as the environment of the stack they belong to; however, for imported resources (those obtained from static methods like fromRoleArn, fromBucketName, etc.), that might be different than the stack they were imported into.

Return type: ResourceEnvironment

node¶

The construct tree node associated with this construct.

Return type: ConstructNode

rule_arn¶

events:us-east-2:123456789012:rule/example.

Type: The value of the event rule Amazon Resource Name (ARN), such as arn
Type: aws
Return type: str

rule_name¶

The name event rule.

Return type: str

stack¶

The stack in which this resource is defined.

Return type: Stack

Static Methods

classmethod from_event_rule_arn(scope, id, event_rule_arn)¶

Import an existing EventBridge Rule provided an ARN.

Parameters

scope (Construct) – The parent creating construct (usually this).
id (str) – The construct’s name.
event_rule_arn (str) – Event Rule ARN (i.e. arn:aws:events:::rule/MyScheduledRule).

Return type

IRule

classmethod is_construct(x)¶

Return whether the given object is a Construct.

Parameters

x (Any) –

Return type

bool

classmethod is_resource(construct)¶

Check whether the given construct is a Resource.

Parameters

construct (IConstruct) –

Return type

bool