Amazon EventBridge FAQs

Q:What is Amazon EventBridge?
Amazon EventBridge is a service that provides real-time access to changes in data in Amazon Web Services services, your own applications and Software-as-a-Service (SaaS) applications without writing code. To get started, you can choose an event source on the Amazon EventBridge console, and select a target from a number of Amazon Web Services services including Amazon Lambda, Amazon SNS, and Amazon Kinesis Data Firehose. Amazon EventBridge will automatically deliver the events in near real-time.

Q: How can I get started using Amazon EventBridge?
Log in to your Amazon Web Services account, navigate to the Amazon EventBridge console, and choose an event source from a list of partner SaaS applications and Amazon Web Services services. If you are using a partner application ensure that you have configured your SaaS account to emit events, and accept it in the offered event sources section of the Amazon EventBridge console. Amazon EventBridge will automatically create an event bus for you to which events will be routed. Alternatively, you can use the Amazon SDK to instrument your application to start emitting events to your event bus. Optionally configure a filtering rule and attach a target for your events, for example, this can be a Lambda function. Amazon EventBridge will be automatically ingest, filter and send the events to the configured target in a secure and highly available way.

Q: Can I publish my own events to Amazon EventBridge?
Yes. Customers can generate custom application-level events and publish them to Amazon EventBridge via the service’s APIs. Customers can also set up scheduled events that are generated on a periodic basis, and can process these events in any of the Amazon EventBridge supported targets.

Q: What is the format of an event?
Events use a specific JSON structure. Every event has the same top-level envelope fields, such as the source of the event, timestamp, and region. This is followed by a detail field which is the body of the event. For example, when an Amazon EC2 auto scaling group creates a new Amazon EC2 instance, it emits an event with source: “aws.autoscaling” and detail: "EC2 instance created successfully".

Q: How do I filter which events are delivered to a target?
You can filter events with rules. A rule matches incoming events for a given event bus and routes them to targets for processing. A single rule can route to multiple targets, all of which are processed in parallel. Rules allow different application components to look for and process the events that are of interest to them. A rule can customize an event before it is sent to the target, by passing only certain parts or by overwriting it with a constant. For the example given in the previous question, you can create an event rule that matches on source: “aws.autoscaling” and detail: "EC2 instance created successfully" to be notified any time an auto scaling group successfully creates an Amazon EC2 instance.

Q: How do I secure access to Amazon EventBridge?
Amazon EventBridge integrates with Amazon Identity and Access Management (IAM) so that you can specify which actions a user in your Amazon Web Services Account can perform. For example, you could create an IAM policy that gives only certain users in your organization permission to create event buses or attach event targets.

Q: How does Amazon EventBridge relate to CloudWatch Events?
Amazon EventBridge builds upon and extends CloudWatch Events. It uses the same service API and endpoint, and the same underlying service infrastructure. For existing CloudWatch Events customers, nothing changes - you can continue to use the same API, CloudFormation templates, and console. We heard from customers that CloudWatch Events is the ideal service for building event-driven architectures, and so we built new features that would enable our customers to connect data from their own apps and third-party SaaS apps. Rather than keeping this beneath the CloudWatch service, we have released this functionality with a new name, Amazon EventBridge, to signify the expansion beyond the monitoring use case that CloudWatch Events was developed for.

Q: I currently use Amazon CloudWatch Events and I WANT to try the features of Amazon EventBridge. Do I need to move my Amazon Cloudwatch Events rules and persmissions to Amazon EventBridge?
No. Existing Amazon CloudWatch Events users can access their existing default bus, rules, and events in the new Amazon EventBridge console and API or in the Amazon CloudWatch Events console and API.

Q: I’m already using Amazon CloudWatch Events and I don’t need the features of Amazon EventBridge. What will change for me?
Nothing. Amazon EventBridge uses the same Amazon CloudWatch Events API so all of your existing CloudWatch Events API usage will remain the same.

Q: Are you going to deprecate Amazon CloudWatch Events one day?
No, we are not going to deprecate the API or the service itself. Amazon EventBridge is using the same API, and has added additional features. Over time, the Amazon CloudWatch Events name will be replaced with Amazon EventBridge.

Q: Which Amazon Web Services services are integrated as event sources for Amazon EventBridge?
There are over 90 Amazon Web Services services available as event sources for EventBridge, including Amazon Lambda, Amazon Kinesis, Amazon Fargate, and Amazon S3. For a full list of Amazon Web Services service integrations, see the EventBridge documentation.

Q: Which Amazon Web Services services are integrated as event targets for Amazon EventBridge?
There are over 15 Amazon Web Services services available as event targets for EventBridge including Amazon Lambda, Amazon SQS, Amazon SNS, and Amazon Kinesis Streams. For a full list of Amazon Web Services service integrations please see the EventBridge documentation.

Q: What are the service limits?
See “Service Limits” page here.

Q: What is the latency I can expect between sending and receiving an event?

Typical latency is about half a second. Note that this can vary.

Q: Does Amazon EventBridge support resource tagging?
Yes, you can tag rules. You can’t tag event buses or event sources.

Q: What throughput can I expect from Amazon EventBridge?
Event bus throughput limits are given in the “Service Limits” page here. If you require higher throughput please request a service limit increase through the Amazon Web Services Support Center by choosing Create Case and then choosing Service Limit Increase.

Q: What does event bridge cost?
Please see Pricing here.

Q: Will I be charged for events sent by a partner to an event source that does not have an event bus attached?
No.

Q: Can I have a target that sends events to another account?
Yes. These are called cross-account events, and you can have a target that is either the default event bus or any other event bus in another account.

Q: Can I use Amazon CloudFormation with Amazon EventBridge?
Amazon CloudFormation is supported for Rules and EventBusPolicy resources. Event bus and event source resources are not yet supported, but will be in the future.

Q: When should I use Amazon EventBridge and when should I use Amazon SNS?
Both Amazon EventBridge and Amazon SNS can be used to develop event-driven applications, and your choice will depend on your specific needs. Amazon EventBridge is recommended when you want to build an application that reacts to events from SaaS applications and/or Amazon Web Services services. Amazon EventBridge is the only event-based service that integrates directly with third-party SaaS partners. Amazon EventBridge also automatically ingests events from over 90 Amazon Web Services services without requiring developers to create any resources in their account. Further, Amazon EventBridge uses a defined JSON-based structure for events, and allows you to create rules that are applied across the entire event body to select events to forward to a target. Amazon EventBridge currently supports over 15 Amazon Web Services services as targets, including Amazon Lambda, Amazon SQS, Amazon SNS, and Amazon Kinesis Streams and Firehose, among others. At launch, Amazon EventBridge is has limited throughput (see Service Limits) which can be increased upon request, and typical latency of around half a second.
Amazon SNS is recommended when you want to build an application that reacts to high throughput or low latency messages published by other applications or microservices (as Amazon SNS provides nearly unlimited throughput), or for applications that need very high fan-out (thousands or millions of endpoints). Messages are unstructured and can be in any format. Amazon SNS supports forwarding messages to 6 different types of targets, including Amazon Lambda, Amazon SQS, HTTP/S endpoints, SMS, Mobile Push, and email. Amazon SNS typical latency is under 30 msec. A wide range of Amazon Web Services services send SNS messages by configuring the service to do so (more than 30, including Amazon EC2, Amazon S3, and Amazon RDS).

Q: Why would I integrate my SaaS application with Amazon EventBridge?
Amazon EventBridge makes it easy for SaaS vendors to integrate their service into their customers’ event-driven architectures built on Amazon Web Services. Amazon EventBridge makes your product directly accessible to millions of Amazon Web Services developers, unlocking new use cases. It offers a fully auditable, secure, and scalable pathway to send events without the SaaS vendor managing any eventing infrastructure.

Q: How much effort will be required for a SaaS Partner to integrate with Amazon EventBridge?
Partners who already support a webhook or other push-based integration mode can expect to perform less than 5 days of development to integrate with Amazon EventBridge.